JP2012104719A - Method of manufacturing semiconductor device and substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor device capable of manufacturing a capacitor used in the semiconductor device with efficiency and a small occupied area, and to provide a substrate processing apparatus.SOLUTION: A method of manufacturing a semiconductor device comprises: a step (S104) of forming a lower electrode on a substrate 200; steps (S106, S108, and S110) of forming a dielectric film by stacking three kinds of metal oxide films each containing a different metal element; and a step (S112) of forming an upper electrode on the dielectric film, wherein each step is performed by the same apparatus.

Description

  The present invention relates to a semiconductor device manufacturing method and a substrate processing apparatus.

  Patent Document 1 discloses a film forming technique for manufacturing a capacitor suitably used in a semiconductor device, for example, a DRAM (Dynamic Random Access Memory).

JP 2009-134148 A

  When manufacturing a capacitor used in a semiconductor device such as a DRAM (Dynamic Random Access Memory), it is required to perform it efficiently and with a small occupied floor area.

  A main object of the present invention is to provide a method of manufacturing a semiconductor device and a substrate processing apparatus capable of efficiently performing a capacitor used in the semiconductor device with a small occupied floor area.

According to the present invention,
Forming a lower electrode on the substrate;
Forming a dielectric film by laminating three kinds of metal oxide films each containing a different metal element on the lower electrode;
Forming an upper electrode on the dielectric film;
There is provided a method for manufacturing a semiconductor device in which the steps are performed by the same apparatus.

Moreover, according to the present invention,
A processing chamber for accommodating the substrate;
A first raw material supply system for supplying a first raw material containing a first metal element to the processing chamber;
A second raw material supply system for supplying a second raw material containing a second metal element different from the first metal element to the processing chamber;
A third raw material supply system for supplying a third raw material containing a third metal element different from the first metal element and the second metal element to the processing chamber;
An oxidizing agent supply system for supplying an oxidizing agent to the processing chamber;
A nitriding agent supply system for supplying a nitriding agent to the processing chamber;
The first raw material and the oxidizing agent are alternately supplied to the processing chamber to form a first metal oxide film, and then the second raw material and the oxidizing agent are processed on the first metal oxide film. A second metal oxide film is formed by alternately supplying to the chamber, and a third metal oxide film is formed by alternately supplying the third raw material and the oxidizing agent to the processing chamber on the second metal oxide film. A dielectric film having the first metal oxide film, the second metal oxide film, and the third metal oxide film is formed on the substrate by forming a film, and the third raw material and the nitriding agent are formed. The first raw material supply system, the second raw material supply system, the third raw material supply system, and the oxidant supply so as to form an upper electrode on the dielectric film by alternately supplying the gas to the processing chamber A control unit for controlling the system and the nitriding agent supply system;
A substrate processing apparatus is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method and substrate processing apparatus of a semiconductor device which can perform the capacitor used for a semiconductor device efficiently and with a small occupied floor area are provided.

FIG. 1 is a schematic perspective view for explaining the configuration of a substrate processing apparatus suitably used in a preferred embodiment of the present invention. FIG. 2 is a schematic configuration diagram of an example of a processing furnace and its accompanying members suitably used in a preferred embodiment of the present invention, and is a diagram showing a processing furnace part in a schematic longitudinal section. FIG. 3 is a schematic longitudinal sectional view taken along line AA of the processing furnace shown in FIG. FIG. 4 is a flowchart for explaining a manufacturing process of the MIM capacitor in the preferred embodiment of the present invention. FIG. 5A is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 5B is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 5C is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 5D is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 5E is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 5F is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 5G is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 5H is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 5I is a schematic longitudinal sectional view for explaining the method for manufacturing the MIM capacitor in the preferred embodiment of the present invention. FIG. 6 is a flowchart for explaining the manufacturing process of the lower electrode of the MIM capacitor in the preferred embodiment of the present invention. FIG. 7 is a timing chart for explaining the manufacturing process of the lower electrode of the MIM capacitor in the preferred embodiment of the present invention. FIG. 8 is a flowchart for explaining the manufacturing process of the dielectric film of the MIM capacitor in the preferred embodiment of the present invention. FIG. 9 is a timing chart for explaining the manufacturing process of the dielectric film of the MIM capacitor in the preferred embodiment of the present invention. FIG. 10 is a flowchart for explaining the manufacturing process of the upper electrode of the MIM capacitor in the preferred embodiment of the present invention. FIG. 11 is a timing chart for explaining the manufacturing process of the upper electrode of the MIM capacitor in the preferred embodiment of the present invention. FIG. 12 is a flowchart for explaining a gas cleaning process in a preferred embodiment of the present invention. FIG. 13 is a timing chart for explaining a gas cleaning process in a preferred embodiment of the present invention. FIG. 14 is a diagram for explaining the time reduction effect in the present embodiment. FIG. 15 is a flowchart for explaining a modification of the manufacturing process of the MIM capacitor in the preferred embodiment of the present invention. FIG. 16 is a flowchart for explaining another modified example of the manufacturing process of the MIM capacitor in the preferred embodiment of the present invention.

In the manufacturing process of a DRAM capacitor, a thin film and a high quality film forming technique are required. Conventionally, a titanium nitride film (TiN film) is formed as a lower electrode by a CVD method, and a zirconium oxide film (ZrO ₂ film) and an alumina oxide film (Al ₂ O ₃ film) are formed thereon by ALD (Atomic). A dielectric film was formed by forming a film by a layer deposition method, and a titanium nitride film (TiN film) was formed as an upper electrode by a CVD method on the dielectric film.

In a capacitor of a DRAM element having a half pitch of 45 nm or less, the electrode area of the capacitor is reduced with the miniaturization, and it is difficult to secure a capacity with the Al ₂ O ₃ film and the ZrO ₂ film as the dielectric films. Research for adopting a titanium oxide film (TiO ₂ film) having a higher relative dielectric constant has been actively conducted.

  Moreover, in order to ensure the capacity, the capacitor structure is also formed in, for example, a cylindrical solid shape, and the shape has also been reduced, so the film was formed by the thermal CVD method used as the upper and lower electrodes. In the TiN film, it has become difficult to form a uniform film.

  As described above, in the manufacturing process of 45 nm class or less, it is highly necessary to introduce new technologies for both the dielectric film and the electrode film, which is a big problem in terms of quality and equipment investment.

  The present inventors have devised the following preferred embodiments as a result of intensive studies in consideration of such problems.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  First, a substrate processing apparatus suitably used in a preferred embodiment of the present invention will be described. This substrate processing apparatus is configured as an example of a semiconductor manufacturing apparatus used for manufacturing a semiconductor device.

  In the following description, as an example of the substrate processing apparatus, a case will be described in which a vertical apparatus that performs a film forming process or the like on a substrate is used. However, the present invention is not based on the use of a vertical apparatus, and for example, a single wafer apparatus may be used.

  Referring to FIG. 1, a substrate processing apparatus 101 uses a cassette 110 that contains a wafer 200 as an example of a substrate, and the wafer 200 is made of a material such as semiconductor silicon. The substrate processing apparatus 101 includes a housing 111, and a cassette stage 114 is installed inside the housing 111. The cassette 110 is carried on the cassette stage 114 by an in-process transfer device (not shown) or unloaded from the cassette stage 114.

  The cassette 110 is placed on the cassette stage 114 by an in-process transfer device (not shown) so that the wafer 200 in the cassette 110 maintains a vertical posture and the wafer loading / unloading port of the cassette 110 faces upward. The The cassette stage 114 rotates the cassette 110 clockwise 90 degrees rearward of the casing 111 so that the wafer 200 in the cassette 110 is in a horizontal posture, and the wafer loading / unloading port of the cassette 110 faces the rear of the casing 111. It is configured to be operable.

  A cassette shelf 105 is installed in a substantially central portion of the casing 111 in the front-rear direction, and the cassette shelf 105 is configured to store a plurality of cassettes 110 in a plurality of rows and a plurality of rows. The cassette shelf 105 is provided with a transfer shelf 123 in which the cassette 110 to be transferred by the wafer transfer mechanism 125 is stored.

  A reserve cassette shelf 107 is provided above the cassette stage 114, and is configured to store the cassette 110 in a preliminary manner.

  A cassette carrying device 118 is installed between the cassette stage 114 and the cassette shelf 105. The cassette carrying device 118 includes a cassette elevator 118a that can move up and down while holding the cassette 110, and a cassette carrying mechanism 118b as a carrying mechanism. The cassette carrying device 118 is configured to carry the cassette 110 among the cassette stage 114, the cassette shelf 105, and the spare cassette shelf 107 by an interlocking operation of the cassette elevator 118a and the cassette carrying mechanism 118b.

  A wafer transfer mechanism 125 is installed behind the cassette shelf 105. The wafer transfer mechanism 125 includes a wafer transfer device 125a capable of rotating or linearly moving the wafer 200 in the horizontal direction, and a wafer transfer device elevator 125b for moving the wafer transfer device 125a up and down. The wafer transfer device 125 a is provided with a tweezer 125 c for picking up the wafer 200. The wafer transfer device 125 loads (charges) the wafer 200 to the boat 217 using the tweezers 125c as the placement portion of the wafer 200 by the interlocking operation of the wafer transfer device 125a and the wafer transfer device elevator 125b. The boat 217 is configured to be detached (discharged).

  A processing furnace 202 for heat-treating the wafer 200 is provided above the rear portion of the casing 111, and a lower end portion of the processing furnace 202 is configured to be opened and closed by a furnace port shutter 147.

  Below the processing furnace 202, a boat elevator 115 that raises and lowers the boat 217 with respect to the processing furnace 202 is provided. An arm 128 is connected to the lifting platform of the boat elevator 115, and a seal cap 219 is horizontally installed on the arm 128. The seal cap 219 is configured to support the boat 217 vertically and to close the lower end portion of the processing furnace 202.

  The boat 217 includes a plurality of holding members, and is configured to hold a plurality of (for example, about 50 to 150) wafers 200 horizontally with the centers thereof aligned in the vertical direction. Yes.

  Above the cassette shelf 105, a clean unit 134a for supplying clean air that is a cleaned atmosphere is installed. The clean unit 134 a includes a supply fan (not shown) and a dustproof filter (not shown), and is configured to distribute clean air inside the casing 111.

  A clean unit 134 b that supplies clean air is installed at the left end of the housing 111. The clean unit 134b also includes a supply fan (not shown) and a dustproof filter (not shown), and is configured to circulate clean air in the vicinity of the wafer transfer device 125a, the boat 217, and the like. The clean air is exhausted to the outside of the casing 111 after circulating in the vicinity of the wafer transfer device 125a, the boat 217, and the like.

  Next, main operations of the substrate processing apparatus 101 will be described.

  When the cassette 110 is loaded onto the cassette stage 114 by an in-process transfer device (not shown), the cassette 110 holds the wafer 200 in a vertical position on the cassette stage 114 and the wafer loading / unloading port of the cassette 110 is directed upward. It is placed on the cassette stage 114 so as to face. Thereafter, the cassette 110 is placed in a clockwise direction 90 in the clockwise direction behind the housing 111 so that the wafer 200 in the cassette 110 is placed in a horizontal posture by the cassette stage 114 and the wafer loading / unloading port of the cassette 110 faces the rear of the housing 111. ° Rotated.

  Thereafter, the cassette 110 is automatically transported and delivered by the cassette transport device 118 to the designated shelf position of the cassette shelf 105 or the spare cassette shelf 107 and temporarily stored, and then the cassette shelf 105 or the spare cassette shelf. It is transferred from 107 to the transfer shelf 123 by the cassette transfer device 118 or directly transferred to the transfer shelf 123.

  When the cassette 110 is transferred to the transfer shelf 123, the wafers 200 are picked up from the cassette 110 by the tweezers 125c of the wafer transfer device 125a through the wafer loading / unloading port of the cassette 110 and loaded (charged) into the boat 217. The wafer transfer device 125 a that has delivered the wafer 200 to the boat 217 returns to the cassette 110 and loads the subsequent wafer 200 into the boat 217.

  When a predetermined number of wafers 200 are loaded into the boat 217, the furnace port shutter 147 that has closed the lower end of the processing furnace 202 is opened, and the lower end of the processing furnace 202 is opened. Thereafter, the boat 217 holding the wafer group 200 is loaded into the processing furnace 202 by the ascending operation of the boat elevator 115, and the lower part of the processing furnace 202 is closed by the seal cap 219.

  After loading, arbitrary processing is performed on the wafer 200 in the processing furnace 202. After the processing, the wafer 200 and the cassette 110 are carried out of the casing 111 in the reverse procedure described above.

  Next, the processing furnace 202 used in the substrate processing apparatus 101 described above will be described with reference to FIGS.

  2 and 3, the processing furnace 202 is provided with a heater 207 which is a heating device (heating means) for heating the wafer 200. The heater 207 includes a cylindrical heat insulating member whose upper portion is closed and a plurality of heater wires, and has a unit configuration in which the heater wires are provided on the heat insulating member. A heating power source 250 that supplies power to the heater 207 is provided. A quartz reaction tube 203 for processing the wafer 200 is provided inside the heater 207.

  A manifold 209 is provided below the reaction tube 203. An annular flange is provided at each of the lower end of the reaction tube 203 and the upper opening end of the manifold 209, and an airtight member (hereinafter referred to as an O-ring) 220 is disposed between the flanges. Has been.

  Below the manifold 209, a seal cap 219 is provided as a furnace port lid that can airtightly close the lower end opening of the manifold 209. The seal cap 219 is brought into contact with the lower end of the manifold 209 from the lower side in the vertical direction. The seal cap 219 is made of a metal such as stainless steel and has a disk shape. An airtight member (hereinafter referred to as an O-ring) 220 is disposed between an annular flange provided at the lower opening end of the manifold 209 and the upper surface of the seal cap 219, and the space between the two is hermetically sealed. A processing chamber 201 is formed by at least the reaction tube 203, the manifold 209, and the seal cap 219.

  The seal cap 219 is provided with a boat support 218 that supports the boat 217. The boat 217 includes a bottom plate 210 fixed to the boat support 218 and a top plate 211 disposed above the bottom plate 210, and a plurality of support columns 212 are constructed between the bottom plate 210 and the top plate 211. (See FIG. 1). A plurality of wafers 200 are held on the boat 217. The plurality of wafers 200 are stacked in multiple stages in the tube axis direction of the reaction tube 203 while being held in a horizontal posture while being spaced apart from each other, and are supported by the columns 212 of the boat 217.

  A rotation mechanism 267 for rotating the boat is provided on the side of the seal cap 219 opposite to the processing chamber 201. The rotation shaft 255 of the rotation mechanism 267 passes through the seal cap and is connected to the boat support 218, and the wafer 200 is rotated by rotating the boat 217 via the boat support 218 by the rotation mechanism 267.

  The seal cap 219 is raised and lowered in the vertical direction by a boat elevator 115 as an elevating mechanism provided outside the reaction tube 203, so that the boat 217 can be carried into and out of the processing chamber 201.

  In the processing furnace 202 described above, in a state where a plurality of wafers 200 to be batch-processed are stacked on the boat 217 in multiple stages, the boat 217 is inserted into the processing chamber 201 while being supported by the boat support 218, and the heater 207 is The wafer 200 inserted into the processing chamber 201 is heated to a predetermined temperature.

  2 and 3, five gas supply pipes 310, 320, 330, 340, and 350 for supplying a source gas and an etching gas are connected to the processing chamber 201.

  The gas supply pipe 310 includes a gas supply pipe 311 and a gas supply pipe 312. The gas supply pipe 311 is provided with a liquid mass flow controller 313 that is a flow rate control device (flow rate control means), a vaporizer 315 that is a vaporization unit (vaporization means), and a valve 316 that is an on-off valve in order from the upstream side. The gas supply pipe 312 is provided with a mass flow controller 314 that is a flow rate control device (flow rate control means) and a valve 317 that is an on-off valve in order from the upstream side. The gas supply pipe 311 and the gas supply pipe 312 are connected to the downstream side of the valve 316 and the valve 317 to form a gas supply pipe 310. The gas supply pipe 310 is provided with a valve 318 downstream from the connection point between the gas supply pipe 311 and the gas supply pipe 312.

  The downstream end of the gas supply pipe 310 is provided through the manifold 209, and the lower end of the nozzle 410 is connected to the tip of the gas supply pipe 310 inside the manifold 209. The nozzle 410 is an arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200, and extends in the vertical direction (the loading direction of the wafer 200) along the inner wall of the reaction tube 203. A large number of gas supply holes 410 a for supplying a source gas are provided on the side surface of the nozzle 410. The gas supply holes 410a have the same or inclined opening area from the lower part to the upper part, and are provided at the same pitch.

  Further, the gas supply pipe 310 is provided with a vent line 610 and a valve 614 connected to an exhaust pipe 232 described later between the valve 316 and the valve 317 and the valve 318.

  Mainly by gas supply pipe 310, valve 318, gas supply pipe 311, liquid mass flow controller 313, vaporizer 315, valve 316, gas supply pipe 312, mass flow controller 314, valve 317, nozzle 410, vent line 610, valve 614 A gas supply system (gas supply means) 301 is configured.

  In addition, a carrier gas supply pipe 510 for supplying a carrier gas is connected to the gas supply pipe 310 on the downstream side of the valve 318. The carrier gas supply pipe 510 is provided with a mass flow controller 512 and a valve 514. A carrier gas supply system (inert gas supply system, inert gas supply means) 501 is mainly configured by the carrier gas supply pipe 510, the mass flow controller 512, and the valve 514.

  In the gas supply pipe 311, the liquid source is adjusted in flow rate by the liquid mass flow controller 313, supplied to the vaporizer 315, vaporized, and supplied as source gas. In the gas supply pipe 312, a gaseous etching gas is supplied with its flow rate adjusted by the mass flow controller 314.

  The valve 316 and the valve 317 are switched to supply either the source gas supplied from the gas supply pipe 311 or the etching gas supplied from the gas supply pipe 312 to the gas supply pipe 310.

  Note that while the source gas or the etching gas is not supplied to the processing chamber 201, the valve 318 is closed, the valve 614 is opened, and the source gas or the etching gas is allowed to flow to the vent line 610 through the valve 614. .

  When supplying the source gas or the etching gas to the processing chamber 201, the valve 614 is closed, the valve 318 is opened, and the source gas or the etching gas is supplied to the gas supply pipe 310 downstream of the valve 318. On the other hand, the flow rate of the carrier gas is adjusted by the mass flow controller 512 and supplied from the carrier gas supply pipe 510 via the valve 514, and the source gas or the etching gas merges with this carrier gas on the downstream side of the valve 318, And supplied to the processing chamber 201.

  The gas supply pipe 320 includes a gas supply pipe 321 and a gas supply pipe 322. The gas supply pipe 321 is provided with a liquid mass flow controller 323 that is a flow rate control device (flow rate control means), a vaporizer 325 that is a vaporization unit (vaporization means), and a valve 326 that is an on-off valve in order from the upstream side. The gas supply pipe 322 is provided with a mass flow controller 324 that is a flow rate control device (flow rate control means) and a valve 327 that is an on-off valve in order from the upstream side. The gas supply pipe 321 and the gas supply pipe 322 are connected to the downstream side of the valve 326 and the valve 327 to form a gas supply pipe 320. The gas supply pipe 320 is provided with a valve 328 downstream from the connection point between the gas supply pipe 321 and the gas supply pipe 322.

  The downstream end of the gas supply pipe 320 is provided through the manifold 209, and the lower end of the nozzle 420 is connected to the tip of the gas supply pipe 320 inside the manifold 209. The nozzle 420 is an arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200, and extends in the vertical direction (the loading direction of the wafer 200) along the inner wall of the reaction tube 203. A large number of gas supply holes 420 a for supplying a source gas are provided on the side surface of the nozzle 420. The gas supply holes 420a have the same or inclined opening area from the lower part to the upper part, and are provided at the same pitch.

  Further, the gas supply pipe 320 is provided with a vent line 620 and a valve 624 connected to an exhaust pipe 232 described later between the valve 326 and the valve 327 and the valve 328.

  Mainly by gas supply pipe 320, valve 328, gas supply pipe 321, liquid mass flow controller 323, vaporizer 325, valve 326, gas supply pipe 322, mass flow controller 324, valve 327, nozzle 420, vent line 620, valve 624 A gas supply system (gas supply means) 302 is configured.

  In addition, a carrier gas supply pipe 520 for supplying a carrier gas is connected to the gas supply pipe 320 on the downstream side of the valve 328. The carrier gas supply pipe 520 is provided with a mass flow controller 522 and a valve 524. A carrier gas supply system (inert gas supply system, inert gas supply means) 502 is mainly configured by the carrier gas supply pipe 520, the mass flow controller 522, and the valve 524.

  In the gas supply pipe 321, the liquid source is adjusted in flow rate by the liquid mass flow controller 323, supplied to the vaporizer 325, vaporized, and supplied as source gas. In the gas supply pipe 322, a gaseous etching gas is supplied with its flow rate adjusted by the mass flow controller 324.

  The valve 326 and the valve 327 are switched to supply either the source gas supplied from the gas supply pipe 321 or the etching gas supplied from the gas supply pipe 322 to the gas supply pipe 320.

  Note that while the source gas or the etching gas is not supplied to the processing chamber 201, the valve 328 is closed, the valve 624 is opened, and the source gas or the etching gas is allowed to flow to the vent line 620 through the valve 624. .

  When supplying the source gas or the etching gas to the processing chamber 201, the valve 624 is closed, the valve 328 is opened, and the source gas or the etching gas is supplied to the gas supply pipe 320 downstream of the valve 328. On the other hand, the flow rate of the carrier gas is adjusted by the mass flow controller 522 and supplied from the carrier gas supply pipe 520 via the valve 524, and the source gas or the etching gas merges with this carrier gas on the downstream side of the valve 328, And supplied to the processing chamber 201.

  The gas supply pipe 330 includes a gas supply pipe 331 and a gas supply pipe 332. The gas supply pipe 331 is provided with a liquid mass flow controller 333 that is a flow rate control device (flow rate control means), a vaporizer 335 that is a vaporization unit (vaporization means), and a valve 336 that is an on-off valve in order from the upstream side. The gas supply pipe 332 is provided with a mass flow controller 334 that is a flow rate control device (flow rate control means) and a valve 337 that is an on-off valve in order from the upstream side. The gas supply pipe 331 and the gas supply pipe 332 are connected to the downstream side of the valve 336 and the valve 337 to form a gas supply pipe 330. The gas supply pipe 330 is provided with a valve 338 downstream from the connection point between the gas supply pipe 331 and the gas supply pipe 332.

  The downstream end of the gas supply pipe 330 is provided through the manifold 209, and the lower end of the nozzle 430 is connected to the tip of the gas supply pipe 330 inside the manifold 209. The nozzle 430 is an arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200, and extends in the vertical direction (the loading direction of the wafer 200) along the inner wall of the reaction tube 203. A large number of gas supply holes 430 a for supplying a raw material gas are provided on the side surface of the nozzle 430. The gas supply holes 430a have the same or inclined opening area from the lower part to the upper part, and are provided at the same pitch.

  Further, the gas supply pipe 330 is provided with a vent line 630 and a valve 634 connected to an exhaust pipe 232 described later between the valve 336 and the valve 337 and the valve 338.

  Mainly by gas supply pipe 330, valve 338, gas supply pipe 331, liquid mass flow controller 333, vaporizer 335, valve 336, gas supply pipe 332, mass flow controller 334, valve 337, nozzle 430, vent line 630, valve 634 A gas supply system (gas supply means) 303 is configured.

  Further, a carrier gas supply pipe 530 for supplying a carrier gas is connected to the gas supply pipe 330 on the downstream side of the valve 338. The carrier gas supply pipe 530 is provided with a mass flow controller 532 and a valve 534. A carrier gas supply system (inert gas supply system, inert gas supply means) 503 is mainly configured by the carrier gas supply pipe 530, the mass flow controller 532, and the valve 534.

  In the gas supply pipe 331, the liquid source is adjusted in flow rate by the liquid mass flow controller 333, supplied to the vaporizer 335, vaporized, and supplied as source gas. In the gas supply pipe 332, a gaseous etching gas is supplied with its flow rate adjusted by the mass flow controller 334.

  The valve 336 and the valve 337 are switched to supply either the source gas supplied from the gas supply pipe 331 or the etching gas supplied from the gas supply pipe 332 to the gas supply pipe 330.

  Note that while the source gas or the etching gas is not supplied to the processing chamber 201, the valve 338 is closed, the valve 634 is opened, and the source gas or the etching gas is allowed to flow to the vent line 630 through the valve 634. .

  When supplying the source gas or the etching gas to the processing chamber 201, the valve 634 is closed, the valve 338 is opened, and the source gas or the etching gas is supplied to the gas supply pipe 330 downstream of the valve 338. On the other hand, the flow rate of the carrier gas is adjusted by the mass flow controller 532 and supplied from the carrier gas supply pipe 530 via the valve 534, and the raw material gas or the etching gas merges with this carrier gas on the downstream side of the valve 338. And supplied to the processing chamber 201.

  The gas supply pipe 340 includes a gas supply pipe 341 and a gas supply pipe 342. The gas supply pipe 341 is provided with a mass flow controller 343 that is a flow rate control device (flow rate control means) and a valve 346 that is an on-off valve in order from the upstream side. The gas supply pipe 342 is provided with a mass flow controller 344 that is a flow rate control device (flow rate control means) and a valve 347 that is an on-off valve in order from the upstream side. The gas supply pipe 341 and the gas supply pipe 342 are connected to the downstream side of the valve 346 and the valve 347 to form a gas supply pipe 340. The gas supply pipe 340 is provided with a valve 348 on the downstream side from the connection point between the gas supply pipe 341 and the gas supply pipe 342.

  The downstream end of the gas supply pipe 340 is provided through the manifold 209, and the lower end of the nozzle 440 is connected to the tip of the gas supply pipe 340 inside the manifold 209. The nozzle 440 is an arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200, and extends in the vertical direction (the loading direction of the wafer 200) along the inner wall of the reaction tube 203. A large number of gas supply holes 440 a for supplying a raw material gas are provided on the side surface of the nozzle 440. The gas supply holes 440a have the same or inclined opening area from the lower part to the upper part, and are provided at the same pitch.

  Further, the gas supply pipe 340 is provided with a vent line 640 and a valve 644 connected to an exhaust pipe 232 described later between the valve 346 and the valve 347 and the valve 348.

  Mainly, a gas supply system (gas) is constituted by a gas supply pipe 340, a valve 348, a gas supply pipe 341, a mass flow controller 343, a valve 346, a gas supply pipe 342, a mass flow controller 344, a valve 347, a nozzle 440, a vent line 640, and a valve 644. Supply means) 304 is configured.

  In addition, a carrier gas supply pipe 540 for supplying a carrier gas is connected to the gas supply pipe 340 on the downstream side of the valve 348. The carrier gas supply pipe 540 is provided with a mass flow controller 542 and a valve 544. A carrier gas supply system (inert gas supply system, inert gas supply means) 504 is mainly configured by the carrier gas supply pipe 540, the mass flow controller 542, and the valve 544.

  In the gas supply pipe 341, the source gas is supplied with the flow rate adjusted by the mass flow controller 343. In the gas supply pipe 342, a gaseous etching gas is supplied with its flow rate adjusted by the mass flow controller 344.

  The valve 346 and the valve 347 are switched to supply either the source gas supplied from the gas supply pipe 341 or the etching gas supplied from the gas supply pipe 342 to the gas supply pipe 340.

  Note that while the source gas or the etching gas is not supplied to the processing chamber 201, the valve 348 is closed, the valve 644 is opened, and the source gas or the etching gas is allowed to flow to the vent line 640 through the valve 644. .

  When supplying the source gas or the etching gas to the processing chamber 201, the valve 644 is closed, the valve 348 is opened, and the source gas or the etching gas is supplied to the gas supply pipe 340 downstream of the valve 348. On the other hand, the flow rate of the carrier gas is adjusted by the mass flow controller 542 and supplied from the carrier gas supply pipe 540 via the valve 544, and the source gas or the etching gas merges with this carrier gas on the downstream side of the valve 348, And supplied to the processing chamber 201.

  The gas supply pipe 350 includes a gas supply pipe 351. The gas supply pipe 351 is provided with a mass flow controller 353 which is a flow rate control device (flow rate control means). The gas supply pipe 351 becomes a gas supply pipe 350 on the downstream side of the mass flow controller 353. A valve 358 is provided in the gas supply pipe 350.

  The downstream end of the gas supply pipe 350 is provided through the manifold 209, and the lower end of the nozzle 450 is connected to the tip of the gas supply pipe 350 inside the manifold 209. The nozzle 450 is an arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200, and extends in the vertical direction (the loading direction of the wafer 200) along the inner wall of the reaction tube 203. A large number of gas supply holes 450 a for supplying a source gas are provided on the side surface of the nozzle 450. The gas supply holes 450a have the same or inclined opening area from the lower part to the upper part, and are provided at the same pitch.

  Further, the gas supply pipe 350 is provided with a vent line 650 and a valve 654 connected to an exhaust pipe 232 described later between the mass flow controller 353 and the valve 358.

  A gas supply system (gas supply means) 304 is mainly configured by the gas supply pipe 350, the valve 358, the gas supply pipe 351, the mass flow controller 353, the nozzle 450, the vent line 650, and the valve 654.

  In addition, a carrier gas supply pipe 550 for supplying a carrier gas is connected to the gas supply pipe 350 on the downstream side of the valve 358. The carrier gas supply pipe 550 is provided with a mass flow controller 552 and a valve 554. A carrier gas supply system (inert gas supply system, inert gas supply means) 505 is mainly configured by the carrier gas supply pipe 550, the mass flow controller 552, and the valve 554.

  In the gas supply pipe 351, the raw material gas is supplied with its flow rate adjusted by the mass flow controller 353.

  Note that while the source gas is not supplied to the processing chamber 201, the valve 358 is closed, the valve 654 is opened, and the source gas is allowed to flow to the vent line 650 through the valve 654.

  When supplying the source gas to the processing chamber 201, the valve 654 is closed, the valve 358 is opened, and the source gas is supplied to the gas supply pipe 350 downstream of the valve 358. On the other hand, the flow rate of the carrier gas is adjusted by the mass flow controller 552 and supplied from the carrier gas supply pipe 550 via the valve 554, and the source gas or the etching gas merges with this carrier gas on the downstream side of the valve 358, And supplied to the processing chamber 201.

  An exhaust pipe 231 that exhausts the atmosphere in the processing chamber 201 is connected to the manifold 209. The exhaust pipe 231 is evacuated via a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 243 as a pressure regulator (pressure adjustment unit). A vacuum pump 246 serving as an exhaust device is connected, and the processing chamber 201 can be evacuated so that the pressure in the processing chamber 201 becomes a predetermined pressure (degree of vacuum). An exhaust pipe 232 on the downstream side of the vacuum pump 246 is connected to a waste gas treatment device (not shown) or the like. The APC valve 243 can open and close the valve to evacuate / stop the evacuation in the processing chamber 201, and further adjust the valve opening to adjust the conductance to adjust the pressure in the processing chamber 201. It is an open / close valve. An exhaust system is mainly configured by the exhaust pipe 231, the APC valve 243, the vacuum pump 246, and the pressure sensor 245.

  A temperature sensor 263 as a temperature detector is installed in the reaction tube 203, and by adjusting the power supplied from the heating power supply 250 to the heater 207 based on the temperature information detected by the temperature sensor 263, the processing chamber The temperature in 201 has a desired temperature distribution. The temperature sensor 263 is configured in an L shape, is introduced through the manifold 209, and is provided along the inner wall of the reaction tube 203.

  A boat 217 is provided at the center in the reaction tube 203. The boat 217 can be moved up and down (in and out) with respect to the reaction tube 203 by the boat elevator 115. When the boat 217 is introduced into the reaction tube 203, the lower end portion of the manifold 209 is hermetically sealed with the seal cap 219 via the O-ring 220. The boat 217 is supported on a boat support 218. In order to improve the uniformity of processing, the boat rotation mechanism 267 is driven to rotate the boat 217 supported by the boat support 218.

  The above mass flow controllers 314, 324, 334, 343, 344, 353, 512, 522, 532, 542, 552, liquid mass flow controllers 313, 323, 333, valves 316, 317, 318, 326, 327, 328, 336, 337, 338, 346, 347, 348, 358, 514, 524, 534, 544, 554, 614, 624, 634, 644, 654, APC valve 243, heating power supply 250, temperature sensor 263, pressure sensor 245, vacuum Each member such as the pump 246, the boat rotation mechanism 267, and the boat elevator 115 is connected to the controller 280. The controller 280 is an example of a control unit (control unit) that controls the overall operation of the substrate processing apparatus 101, and is a mass flow controller 314, 324, 334, 343, 344, 353, 512, 522, 532, 542, 552. And flow adjustment of the liquid mass flow controllers 313, 323, 333, valves 316, 317, 318, 326, 327, 328, 336, 337, 338, 346, 347, 348, 358, 514, 524, 534, 544, 554, 614, 624, 634, 644, 654 open / close operation, APC valve 243 open / close and pressure adjustment operation based on pressure sensor 245, temperature adjustment operation of heater 207 based on temperature sensor 263, start / stop of vacuum pump 246, boat rotation Rotational speed adjustment of mechanism 267, boat electronics And controls each of the lifting operations of over motor 115.

  Next, a method for manufacturing a MIM (Metal-Insulator-Metal) capacitor for DRAM (Dynamic Random Access Memory) will be described with reference to FIGS. 4 and 5A to 5I.

First, a field effect transistor (not shown) is formed on a wafer 200 made of semiconductor silicon. Thereafter, as shown in FIG. 5A, a contact 12 connected to a field effect transistor (not shown) through polysilicon 13 in an interlayer insulating film 11 made of SiO ₂ or the like is formed on the polysilicon 13 with titanium (Ti). Etc.

  Thereafter, as shown in FIG. 5A, a silicon nitride film (SiN film) 14 is formed by a CVD (Chemical Vapor deposition) method. The silicon nitride film 14 is used as an etching stopper. Thereafter, a silicon oxide film (SiO film) 16 is formed on the silicon nitride film 14 by a CVD method. The silicon oxide film 16 is used as a sacrificial film. Thereafter, a silicon nitride film (SiN film) 18 is formed on the silicon oxide film 16 by a CVD method. The silicon nitride film 18 is used as an etching stopper.

  Thereafter, as shown in FIG. 5B, a cylinder hole 20 is formed (step S102 in FIG. 4). Using a photoresist (not shown) selectively formed in a predetermined shape as a mask, the silicon nitride film 18, the silicon oxide film 16, and the silicon nitride film 14 are selectively removed by an anisotropic etching method such as a dry etching method. The cylinder hole 20 with the contact 12 exposed is formed at the bottom.

  Thereafter, as shown in FIG. 5C, a titanium nitride film (TiN film) 22 is formed on the entire surface.

  Thereafter, as shown in FIG. 5D, a silicon oxide film (SiO film) 24 is formed on the entire surface by the CVD method, and the cylinder hole 20 is buried.

  Thereafter, as shown in FIG. 5E, the silicon oxide film 24 and the titanium nitride film 22 and the silicon nitride film 18 on the silicon oxide film 16 are polished and removed by CMP (Chemical Mechanical Polishing) polishing, and the side surface of the cylinder hole 20 is removed. The electrode is separated into a lower electrode 23 made of a titanium nitride film 22 on the bottom surface.

  Thereafter, as shown in FIG. 5F, the silicon oxide film 16 and the silicon oxide film 24 are removed by etching to form the lower electrode 23 made of the titanium nitride film 22 (step S104 in FIG. 4).

Thereafter, as shown in FIG. 5G, a ZrO ₂ film 32 is formed (step S106 in FIG. 4).

Thereafter, as shown in FIG. 5G, an Al ₂ O ₃ film 34 is formed (step S108 in FIG. 4).

Thereafter, as shown in FIG. 5G, a TiO ₂ film 36 is formed (step S110 in FIG. 4).

In this way, the dielectric film 30 composed of the ZrO ₂ film 32, the Al ₂ O ₃ film 34, and the TiO ₂ film 36 is formed.

Thereafter, as shown in FIG. 5H, the upper electrode 43 made of the titanium nitride film 42 is formed (step S112 in FIG. 4). Thus, the lower electrode 23 made of the titanium nitride film 22, the dielectric film 30 made of the ZrO ₂ film 32, the Al ₂ O ₃ film 34 and the TiO ₂ film 36, and the upper electrode 43 made of the titanium nitride film 42 are provided. A DRAM MIM capacitor is formed.

  Thereafter, gas cleaning is performed (step S114 in FIG. 4).

  After that, on the other hand, an interlayer insulating film 52 is formed as shown in FIG. 5I.

  Next, among the processes described above, a process performed using the above-described substrate processing apparatus 101 will be described. The following steps are performed under the control of the controller 280.

(Formation of lower electrode 23 (titanium nitride film 22): Step S104)
First, with reference to FIGS. 6, 7, and 1 to 3, a film forming process of the titanium nitride film 22 for forming the lower electrode 23 (see step S <b> 104 in FIG. 4 and FIG. 5C) will be described.

  The heating power supply 250 that supplies power to the heater 207 is controlled to keep the inside of the processing chamber 201 at a temperature in the range of, for example, 300 ° C. to 550 ° C., and preferably 430 ° C.

  After that, when the plurality of wafers 200 in which the cylinder holes 20 are formed (see FIG. 5B) are loaded (wafer charge) into the boat 217 (step S201), the boat 217 supporting the plurality of wafers 200 becomes the boat elevator. It is lifted by 115 and carried into the processing chamber 201 (boat loading) (step S202). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220.

  Thereafter, the boat 217 is rotated by the boat driving mechanism 267 to rotate the wafer 200. Thereafter, the APC valve 243 is opened and the inside of the processing chamber 201 is evacuated by the vacuum pump 246. When the temperature of the wafer 200 reaches 430 ° C. and the temperature is stabilized (step S203), the temperature in the processing chamber 201 is set to 430 ° C. The next steps are sequentially executed in the state held in the above.

  In the present embodiment, the titanium nitride film 22 is formed using an ALD (Atomic Layer Deposition) method. ALD is a method of supplying at least two types of source gases used for film formation to a substrate alternately under a certain film formation condition (temperature, etc.) and adsorbing them on the substrate in units of one atom. This is a technique for performing film formation by utilizing surface reaction. At this time, the film thickness is controlled by the number of cycles in which the source gas is supplied (for example, if the film forming speed is 1 kg / cycle, 20 cycles are performed when a 20 mm film is formed).

(TiCl ₄ supply: Step S204)
In step S <b> 204, TiCl ₄ is supplied into the processing chamber 201 from the gas supply pipe 331 of the gas supply system 303. The gas supply system 303 is configured as a raw material supply system for a raw material containing Ti element. Valve 337 is closed and valve 336 is opened. TiCl ₄ is a liquid at normal temperature, and the flow rate of the liquid TiCl ₄ is adjusted by the liquid mass flow controller 333, supplied to the vaporizer 335, and vaporized by the vaporizer 335. Before supplying TiCl ₄ to the processing chamber 201, the valve 338 is closed, the valve 634 is opened, and TiCl ₄ is allowed to flow to the vent line 630 through the valve 634. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 532.

When supplying TiCl ₄ to the processing chamber 201, the valve 634 is closed, the valve 338 is opened, TiCl ₄ is supplied to the gas supply pipe 330 downstream of the valve 338, and the valve 534 is opened to open the carrier. Gas (N ₂ ) is supplied from the carrier gas supply pipe 530. TiCl ₄ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 338 and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 via the nozzle 430. At this time, the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within a range of 20 to 50 Pa, for example, 30 Pa. The supply amount of TiCl ₄ controlled by the liquid mass flow controller 312 is 1.0 to 2.0 g / min. The time for exposing the wafer 200 to TiCl ₄ is 3 to 10 seconds.

At this time, the only gases flowing into the processing chamber 201 are TiCl ₄ and N ₂ that is an inert gas, and NH ₃ does not exist. Therefore, TiCl ₄ does not cause a gas phase reaction, and reacts with the surface of the wafer 200 and the base film (chemical adsorption) to form an adsorption layer or a Ti layer (hereinafter referred to as Ti-containing layer) of the raw material (TiCl ₄ ). Form. The adsorption layer of TiCl ₄ includes a discontinuous adsorption layer as well as a continuous adsorption layer of raw material molecules. The Ti layer includes not only a continuous layer composed of Ti but also a Ti thin film formed by overlapping these layers. In addition, the continuous layer comprised by Ti may be called Ti thin film.

At the same time, when the valve 554 is opened from the carrier gas supply pipe 550 connected to the middle of the gas supply pipe 350 and N ₂ (inert gas) is allowed to flow, TiCl ₄ is transferred to the NH ₃ side nozzle 450 and the gas supply pipe 350. It can prevent wrapping around. Similarly, when N ₂ (inert gas) is flowed from the carrier gas supply pipe 510 connected to the middle of the gas supply pipe 310 at the same time and N ₂ (inert gas) flows, TiCl ₄ wraps around the nozzle 410 and the gas supply pipe 310. When the valve 524 is opened from the carrier gas supply pipe 520 connected to the middle of the gas supply pipe 320 and N ₂ (inert gas) is allowed to flow, TiCl _{4 is} supplied to the nozzle 420 and the gas supply pipe 320. When the valve 544 is opened from the carrier gas supply pipe 540 connected in the middle of the gas supply pipe 340 and N ₂ (inert gas) is allowed to flow, the nozzle 440 and the gas supply pipe 340 can be prevented. TiCl ₄ can be prevented from sneaking around.

(Residual TiCl ₄ removal: Step S205)
In step S205, residual TiCl ₄ is removed from the processing chamber 201. The valve 338 of the gas supply pipe 330 is closed to stop the supply of TiCl ₄ to the processing chamber 201, and the valve 634 is opened to flow TiCl ₄ to the vent line 630. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove the residual TiCl ₄ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 330, which is a TiCl ₄ supply line, and further from the gas supply pipe 350 and the gas supply pipes 310, 320, and 340 into the processing chamber 201, The effect of eliminating residual TiCl ₄ is enhanced.

(NH ₃ supply: step S206)
In step S <b> 206, NH ₃ is supplied into the processing chamber 201 from the gas supply pipe 351 of the gas supply system 305. The gas supply system 305 is configured as a nitriding agent supply system that supplies a nitriding agent. NH ₃ is supplied after its flow rate is adjusted by the mass flow controller 353. Before supplying NH ₃ to the processing chamber 201, the valve 358 is closed, the valve 654 is opened, and NH ₃ is allowed to flow to the vent line 650 through the valve 654. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 550.

When supplying NH ₃ to the processing chamber 201, the valve 654 is closed, the valve 358 is opened, and NH ₃ is supplied to the gas supply pipe 350 downstream of the valve 358, and the valve 554 is opened to open the carrier. Gas (N ₂ ) is supplied from the carrier gas supply pipe 550. NH ₃ merges with the carrier gas (N ₂ ) on the downstream side of the valve 358 and is mixed, and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 via the nozzle 450. When flowing NH ₃ , the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within a range of 50 to 1000 Pa, for example, 60 Pa. The supply flow rate of NH ₃ controlled by the mass flow controller 353 is 1 to 10 slm. The time for exposing the wafer 200 to NH ₃ is 10 to 30 seconds.

At the same time, when the valve 534 is opened from the carrier gas supply pipe 530 connected to the gas supply pipe 330 and N ₂ (inert gas) flows, NH ₃ is introduced into the nozzle 430 and the gas supply pipe 330 on the TiCl ₄ side. It can prevent wrapping around. Similarly, when the valve 514 is opened from the carrier gas supply pipe 510 connected to the gas supply pipe 310 at the same time and N ₂ (inert gas) is allowed to flow, NH ₃ flows into the nozzle 410 and the gas supply pipe 310. When the valve 524 is opened from the carrier gas supply pipe 520 connected to the middle of the gas supply pipe 320 and N ₂ (inert gas) is allowed to flow, NH _{3 is} supplied to the nozzle 420 and the gas supply pipe 320. When the valve 544 is opened from the carrier gas supply pipe 540 connected in the middle of the gas supply pipe 340 and N ₂ (inert gas) is allowed to flow, the nozzle 440 and the gas supply pipe 340 can be prevented. It is possible to prevent NH ₃ from wrapping around.

By supplying NH ₃ , the Ti-containing layer chemically adsorbed on the wafer 200 and NH ₃ undergo a surface reaction (chemical adsorption), and a titanium nitride film is formed on the wafer 200.

(Residual NH ₃ removal: Step S207)
In step S207, residual NH ₃ is removed from the processing chamber 201. The supply of the NH ₃ into the processing chamber 201 by closing the valve 358 of the gas supply pipe 350 is stopped, flow NH ₃ to the vent line 650 by opening the valve 654. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove residual NH ₃ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 350 that is an NH ₃ supply line, and further from the gas supply pipe 330 and the gas supply pipes 310, 320, and 340 into the processing chamber 201, The effect of eliminating residual NH ₃ is enhanced.

The above steps S204 to S207 are set as one cycle and are performed at least once (step S208), thereby forming the titanium nitride film 22 having a predetermined thickness on the wafer 200 by using the ALD method (see FIG. 5C). In this case, in each cycle, as described above, the atmosphere composed of TiCl ₄ that is the Ti-containing material in step S204 and the atmosphere composed of NH ₃ that is the nitriding gas in step S206 are processed. Note that the film is formed so as not to mix in the chamber 201.

When the film forming process for forming the titanium nitride film 22 having a predetermined thickness is performed, the inside of the processing chamber 201 is purged with the inert gas by exhausting while supplying an inert gas such as N ₂ into the processing chamber 201. (Gas purge: Step S210). Thereafter, the atmosphere in the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (return to atmospheric pressure: step S212). Thereafter, the seal cap 219 is lowered by the boat elevator 115, the lower end of the manifold 209 is opened, and the processed wafer 200 is carried out of the processing chamber 201 from the lower end of the manifold 209 while being supported by the boat 217 ( Boat unloading: Step S214). Thereafter, the processed wafer 200 is taken out from the boat 217 (wafer discharge: step S216).

  Thereafter, as shown in FIG. 5D, a silicon oxide film 24 is formed on the entire surface, and the cylinder hole 20 is filled. Thereafter, as shown in FIG. 5E, the silicon oxide film 24 and the titanium nitride film 22 on the silicon oxide film 16 are filled. Then, the silicon nitride film 18 is polished and removed, and separated into the lower electrode 23 made of the titanium nitride film 22 on the side and bottom surfaces of the cylinder hole 20, and then the silicon oxide film 16 and the silicon oxide film 24 are formed as shown in FIG. 5F. Is removed by etching to form a lower electrode 23 made of a titanium nitride film 22.

Next, referring to FIGS. 8, 9, and 1 to 3, from the zirconium oxide film (ZrO ₂ film) 32, the aluminum oxide film (Al ₂ O ₃ film) 34, and the titanium oxide film (TiO ₂ film) 36. The film forming process of the dielectric film 30 (see steps S106, S108, S110 in FIG. 4 and FIG. 5G) will be described.

  The heater 207 is controlled to keep the inside of the processing chamber 201 at a temperature in the range of 150 ° C. to 450 ° C., for example, and preferably 250 ° C.

  After that, when the plurality of wafers 200 on which the lower electrode 23 made of the titanium nitride film 22 is formed (see FIG. 5B) are loaded into the boat 217 (wafer charge) (step S301), the plurality of wafers 200 are supported. The boat 217 is lifted by the boat elevator 115 and loaded into the processing chamber 201 (boat loading) (step S302). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220.

  Thereafter, the boat 217 is rotated by the boat driving mechanism 267 to rotate the wafer 200. Thereafter, the APC valve 243 is opened and the inside of the processing chamber 201 is evacuated by the vacuum pump 246. When the temperature of the wafer 200 reaches 250 ° C. and the temperature is stabilized (step S303), the temperature in the processing chamber 201 is increased to 250 ° C. The next steps are sequentially executed in the state held in the above.

Formation of zirconium oxide film (ZrO ₂ film) 32 (step S106), formation of aluminum oxide film (Al ₂ O ₃ film) 34 (step S108), and formation of titanium oxide film (TiO ₂ film) 36 The film (step S110) is performed using the ALD method.

(Formation of Zirconium Oxide Film (ZrO ₂ Film) 32: Step S106)
(TEMAZ supply: step S304)
In step S <b> 304, tetrakisethylmethylaminozirconium (TEMAZ, Zr (NEtMe) ₄ ) is supplied into the processing chamber 201 from the gas supply pipe 311 of the gas supply system 301. The gas supply system 301 is configured as a raw material supply system for a raw material containing a Zr element. Valve 317 is closed and valve 316 is opened. TEMAZ is a liquid at room temperature, and the liquid TEMAZ is adjusted in flow rate by the liquid mass flow controller 313, supplied to the vaporizer 315, and vaporized by the vaporizer 315. Before supplying TEMAZ to the processing chamber 201, the valve 318 is closed, the valve 614 is opened, and TEMAZ is allowed to flow to the vent line 610 through the valve 614. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 512.

When supplying TEMAZ to the processing chamber 201, the valve 614 is closed, the valve 318 is opened, TEMAZ is supplied to the gas supply pipe 310 downstream of the valve 318, the valve 514 is opened, and the carrier gas ( N ₂ ) is supplied from the carrier gas supply pipe 510. The TEMAZ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 318 and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 via the nozzle 410. At this time, the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 in the range of 40 to 266 Pa, for example, 133 Pa. The supply amount of TEMAZ controlled by the liquid mass flow controller 313 is 0.1 to 1.0 g / min. The time for exposing the wafer 200 to TEMAZ is 60 to 300 seconds.

At this time, the only gases flowing into the processing chamber 201 are TEMAZ and N ₂ which is an inert gas, and there is no O ₃ . Therefore, TEMAZ does not cause a gas phase reaction, and reacts with the surface of the wafer 200 and the base film (chemical adsorption) to form a raw material (TEMAZ) adsorption layer or a Zr layer (hereinafter referred to as a Zr-containing layer). . The TEMAZ adsorption layer includes a continuous adsorption layer of raw material molecules and a discontinuous adsorption layer. The Zr layer includes not only a continuous layer composed of Zr but also a Zr thin film formed by overlapping these layers. A continuous layer composed of Zr may be referred to as a Zr thin film.

At the same time, when N ₂ (inert gas) is flowed from the carrier gas supply pipe 540 that is connected to the gas supply pipe 340 and N ₂ (inert gas) is allowed to flow, TEMAZ wraps around the nozzle 440 and the gas supply pipe 340 on the O ₃ side. Can be prevented. Similarly, when N ₂ (inert gas) is caused to flow from the carrier gas supply pipe 520 that is connected to the gas supply pipe 320 at the same time and N ₂ (inert gas) is allowed to flow, TEMAZ will flow to the nozzle 420 and the gas supply pipe 320 on the TMA side. When the valve 534 is opened from the carrier gas supply pipe 530 connected to the middle of the gas supply pipe 330 and N ₂ (inert gas) is allowed to flow, the nozzle 430 and the gas on the TiCl ₄ side can be prevented. When TEMAZ can be prevented from flowing into the supply pipe 330 and at the same time, when the valve 554 is opened from the carrier gas supply pipe 550 connected in the middle of the gas supply pipe 350 and N ₂ (inert gas) flows, the nozzle 450 Further, it is possible to prevent TEMAZ from entering the gas supply pipe 350.

(Residual TEMAZ removal: Step S305)
In step S <b> 305, residual TEMAZ is removed from the processing chamber 201. The valve 318 of the gas supply pipe 310 is closed to stop the supply of TEMAZ to the processing chamber 201, the valve 614 is opened, and TEMAZ is flowed to the vent line 610. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove the residual TEMAZ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 310 that is a TEMAZ supply line and further from the gas supply pipes 320, 330, 340, and 350 into the processing chamber 201, the residual TEMAZ is further eliminated. The effect to do increases.

(O ₃ supply: Step S306)
In step S <b> 306, O ₃ is supplied into the processing chamber 201 from the gas supply pipe 341 of the gas supply system 304. The gas supply system 304 is configured as an oxidant supply system that supplies an oxidant. O ₃ is generated using an ozonizer, and the flow rate is adjusted by a mass flow controller 343 and supplied. Before supplying O ₃ to the processing chamber 201, the valve 348 is closed, the valve 644 is opened, and the O ₃ is allowed to flow to the vent line 640 through the valve 644. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 540.

When supplying O ₃ to the processing chamber 201, the valve 644 is closed, the valve 348 is opened, O ₃ is supplied to the gas supply pipe 340 downstream of the valve 348, and the valve 544 is opened. Gas (N ₂ ) is supplied from the carrier gas supply pipe 540. O ₃ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 348 and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 through the nozzle 440. When flowing O ₃ , the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within a range of 40 to 266 Pa, for example, 133 Pa. The supply flow rate of O ₃ controlled by the mass flow controller 343 is 20 to 40 slm at a concentration of 180 g / m ³ . The time for exposing the wafer 200 to O ₃ is 60 to 300 seconds.

At the same time, when the valve 514 is opened from the carrier gas supply pipe 510 connected to the gas supply pipe 310 and N ₂ (inert gas) is allowed to flow, O ₃ wraps around the nozzle 410 and the gas supply pipe 310 on the TEMAZ side. Can be prevented. Similarly, when N ₂ (inert gas) is allowed to flow from the carrier gas supply pipe 520 connected to the middle of the gas supply pipe 320 at the same time to flow N ₂ (inert gas), O _{3 is} supplied to the nozzle 420 and the gas supply pipe 320 on the TMA side. When the valve 534 is opened from the carrier gas supply pipe 530 connected to the middle of the gas supply pipe 330 and N ₂ (inert gas) is allowed to flow, the nozzle 430 on the TiCl ₄ side When O ₃ can be prevented from flowing into the gas supply pipe 330, and at the same time, when the valve 554 is opened from the carrier gas supply pipe 550 connected to the gas supply pipe 350 and N ₂ (inert gas) is allowed to flow, It is possible to prevent O ₃ from entering the nozzle 450 and the gas supply pipe 350.

By supplying O ₃ , the Zr-containing layer chemically adsorbed on the wafer 200 and O ₃ undergo a surface reaction (chemical adsorption), and a zirconium oxide film is formed on the wafer 200.

(Residual O ₃ removal: Step S307)
In step S307, residual O ₃ is removed from the processing chamber 201. The supply of _{O 3} into the processing chamber 201 by closing the valve 348 of the gas supply pipe 340 is stopped, flow _{O 3} to the vent line 640 by opening the valve 644. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove residual O ₃ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 340 that is an O ₃ supply line and further from the gas supply pipes 310, 320, 330, and 350 into the processing chamber 201, the residual O _{3 is} further increased. The effect of eliminating is increased.

The above steps S304 to S307 are set as one cycle and are performed at least once (step S308), thereby forming a zirconium oxide film 32 having a predetermined film thickness (1.5 to 40 mm) on the wafer 200 by using the ALD method (step S308). (See FIG. 5G). In this case, in each cycle, as described above, the atmosphere composed of the TEMAZ that is the Ti-containing raw material in Step S304 and the atmosphere composed of the O ₃ that is the oxidizing gas in Step S306 are each in the processing chamber. Note that the film is formed so as not to mix in 201.

  When the film forming process for forming the zirconium oxide film 32 having a predetermined film thickness is performed, the process proceeds to the film forming step (S108) of the aluminum oxide film.

(Formation of Aluminum Oxide Film (Al ₂ O ₃ Film) 34: Step S108)
(TMA supply: Step S309)
In step S 309, trimethylaluminum (TMA, Al (CH ₃ ) ₃ ) is supplied into the processing chamber 201 from the gas supply pipe 321 of the gas supply system 302. The gas supply system 302 is configured as a raw material supply system for a raw material containing Al element. Valve 327 is closed and valve 326 is opened. TMA is liquid at normal temperature, and the liquid TMA is adjusted in flow rate by the liquid mass flow controller 323, supplied to the vaporizer 325, and vaporized by the vaporizer 325. Before supplying TMA to the processing chamber 201, the valve 328 is closed, the valve 624 is opened, and the TMA is allowed to flow to the vent line 620 through the valve 624. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 522.

When supplying TMA to the processing chamber 201, the valve 624 is closed, the valve 328 is opened, TMA is supplied to the gas supply pipe 320 downstream of the valve 328, and the valve 524 is opened, so that the carrier gas ( N ₂ ) is supplied from the carrier gas supply pipe 520. TMA is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 328 and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 via the nozzle 420. At this time, the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within a range of 30 to 500 Pa, for example, 60 Pa. The supply amount of TMA controlled by the liquid mass flow controller 323 is 0.1 to 0.5 g / min. The time for exposing the wafer 200 to TEMAZ is 10 seconds.

At this time, the gas flowing into the processing chamber 201 is only TMA and N ₂ which is an inert gas, and there is no O ₃ . Therefore, TMA does not cause a gas phase reaction, and reacts with the surface of the wafer 200 and the base film (chemical adsorption) to form a raw material (TMA) adsorption layer or an Al layer (hereinafter referred to as an Al-containing layer). . The TMA adsorption layer includes a continuous adsorption layer of raw material molecules and a discontinuous adsorption layer. The Al layer includes not only a continuous layer composed of Al but also an Al thin film formed by overlapping these layers. In addition, the continuous layer comprised with Al may be called Al thin film.

At the same time, when N ₂ (inert gas) is flowed from the carrier gas supply pipe 540 connected in the middle of the gas supply pipe 340 and N ₂ (inert gas) is allowed to flow, TMA wraps around the nozzle 440 and the gas supply pipe 340 on the O ₃ side. Can be prevented. Similarly, when N ₂ (inert gas) is allowed to flow from the carrier gas supply pipe 510 that is connected to the gas supply pipe 310 at the same time and N ₂ (inert gas) is allowed to flow, TMA is applied to the nozzle 410 and the gas supply pipe 310 on the TEMAZ side. When the valve 534 is opened from the carrier gas supply pipe 530 connected to the middle of the gas supply pipe 330 and N ₂ (inert gas) is allowed to flow, the nozzle 430 and the gas on the TiCl ₄ side can be prevented. When TMA can be prevented from flowing into the supply pipe 330 and at the same time the valve 554 is opened from the carrier gas supply pipe 550 connected to the gas supply pipe 350 and N ₂ (inert gas) flows, the nozzle 450 In addition, TMA can be prevented from entering the gas supply pipe 350.

(Residual TMA removal: Step S310)
In step S310, residual TMA is removed from the processing chamber 201. The valve 328 of the gas supply pipe 320 is closed to stop the supply of TMA to the processing chamber 201, and the valve 624 is opened to flow TMA to the vent line 620. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, the inside of the processing chamber 201 is exhausted to 20 Pa or less by the vacuum pump 246, and the residual TMA is removed from the processing chamber 201. At this time, if an inert gas such as N ₂ is supplied from the gas supply pipe 320 as a TMA supply line and further from the gas supply pipes 310, 330, 340, and 350 into the processing chamber 201, the residual TMA is further removed. The effect to do increases.

(O ₃ supply: Step S311)
In step S <b> 311, O ₃ is supplied into the processing chamber 201 from the gas supply pipe 341 of the gas supply system 304. O ₃ is generated using an ozonizer, and the flow rate is adjusted by a mass flow controller 343 and supplied. Before supplying O ₃ to the processing chamber 201, the valve 348 is closed, the valve 644 is opened, and the O ₃ is allowed to flow to the vent line 640 through the valve 644. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 540.

When supplying O ₃ to the processing chamber 201, the valve 644 is closed, the valve 348 is opened, O ₃ is supplied to the gas supply pipe 340 downstream of the valve 348, and the valve 544 is opened. Gas (N ₂ ) is supplied from the carrier gas supply pipe 540. O ₃ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 348 and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 through the nozzle 440. When flowing O ₃ , the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within the range of 30 to 500 Pa, for example, 130 Pa. The supply flow rate of O ₃ controlled by the mass flow controller 343 is 15 slm at a concentration of 250 g / m ³ . The time for exposing the wafer 200 to O ₃ is 20 seconds.

At the same time, when the valve 524 is opened from the carrier gas supply pipe 520 connected to the gas supply pipe 320 and N ₂ (inert gas) is allowed to flow, O ₃ circulates into the nozzle 420 and the gas supply pipe 320 on the TMA side. Can be prevented. Similarly, when N ₂ (inert gas) is allowed to flow from the carrier gas supply pipe 510 connected to the middle of the gas supply pipe 310 at the same time to allow N ₂ (inert gas) to flow, O _{3 is} supplied to the nozzle 410 and the gas supply pipe 310 on the TEMAZ side. When the valve 534 is opened from the carrier gas supply pipe 530 connected to the middle of the gas supply pipe 330 and N ₂ (inert gas) is allowed to flow, the nozzle 430 on the TiCl ₄ side When O ₃ can be prevented from flowing into the gas supply pipe 330, and at the same time, when the valve 554 is opened from the carrier gas supply pipe 550 connected to the gas supply pipe 350 and N ₂ (inert gas) is allowed to flow, It is possible to prevent O ₃ from entering the nozzle 450 and the gas supply pipe 350.

By supplying O ₃ , the Al-containing layer chemically adsorbed on the wafer 200 and O ₃ undergo a surface reaction (chemical adsorption), and an aluminum oxide film is formed on the wafer 200.

(Residual O ₃ removal: Step S312)
In step S <b> 311, residual O ₃ is removed from the processing chamber 201. The supply of _{O 3} into the processing chamber 201 by closing the valve 348 of the gas supply pipe 340 is stopped, flow _{O 3} to the vent line 640 by opening the valve 644. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove residual O ₃ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 340 that is an O ₃ supply line and further from the gas supply pipes 310, 320, 330, and 350 into the processing chamber 201, the residual O _{3 is} further increased. The effect of eliminating is increased.

The above steps S309 to S312 are set as one cycle and are performed at least once (step S313), thereby forming an aluminum oxide film 34 having a predetermined thickness (1 to 5 mm) on the wafer 200 by using the ALD method (FIG. 5G). reference). In this case, in each cycle, as described above, each atmosphere of the atmosphere constituted by the TMA that is the Al-containing raw material in Step S309 and the atmosphere constituted by O ₃ that is the oxidizing gas in Step S311 is processed. Note that the film is formed so as not to mix in 201.

  When the film forming process for forming the aluminum oxide film 34 having a predetermined film thickness is performed, the process proceeds to the film forming step (S110) of the titanium oxide film.

(Formation of Titanium Oxide Film (TiO ₂ Film) 36: Step S110)
(TiCl ₄ supply: step S314)
In step S 314, titanium tetrachloride (TiCl ₄ ) is supplied into the processing chamber 201 from the gas supply pipe 331 of the gas supply system 303. Valve 337 is closed and valve 336 is opened. TiCl ₄ is a liquid at normal temperature, and the flow rate of the liquid TiCl ₄ is adjusted by the liquid mass flow controller 333, supplied to the vaporizer 335, and vaporized by the vaporizer 335. Before supplying TiCl ₄ to the processing chamber 201, the valve 338 is closed, the valve 634 is opened, and TiCl ₄ is allowed to flow to the vent line 630 through the valve 634. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 532.

When supplying TiCl ₄ to the processing chamber 201, the valve 634 is closed, the valve 338 is opened, TiCl ₄ is supplied to the gas supply pipe 330 downstream of the valve 338, and the valve 534 is opened to open the carrier. Gas (N ₂ ) is supplied from the carrier gas supply pipe 530. TiCl ₄ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 338 and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 via the nozzle 430. At this time, the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within a range of 30 to 500 Pa, for example, 100 Pa. The supply amount of TiCl ₄ controlled by the liquid mass flow controller 333 is 0.18 to 0.5 g / min. The time for exposing the wafer 200 to TiCl ₄ is 40 seconds.

At this time, the only gases flowing into the processing chamber 201 are TiCl ₄ and N ₂ which is an inert gas, and there is no O ₃ . Therefore, TiCl ₄ does not cause a gas phase reaction, and reacts with the surface of the wafer 200 and the base film (chemical adsorption) to form an adsorption layer or a Ti layer (hereinafter referred to as Ti-containing layer) of the raw material (TiCl ₄ ). Form. The TMA adsorption layer includes a continuous adsorption layer of raw material molecules and a discontinuous adsorption layer. The Ti layer includes not only a continuous layer composed of Ti but also a Ti thin film formed by overlapping these layers. In addition, the continuous layer comprised by Ti may be called Ti thin film.

At the same time, when N ₂ (inert gas) is allowed to flow from the carrier gas supply pipe 540 connected to the middle of the gas supply pipe 340 to allow N ₂ (inert gas) to flow, TiCl ₄ is transferred to the nozzle 440 and the gas supply pipe 340 on the O ₃ side. It can prevent wrapping around. Similarly, when N ₂ (inert gas) is flowed from the carrier gas supply pipe 510 connected to the gas supply pipe 310 at the same time by flowing N ₂ (inert gas), TiCl _{4 is} supplied to the TEMAZ side nozzle 410 and the gas supply pipe 310. When the valve 524 is opened from the carrier gas supply pipe 520 connected to the middle of the gas supply pipe 320 and N ₂ (inert gas) is allowed to flow, the nozzle 420 on the TMA side and the gas can be prevented. When TiCl ₄ can be prevented from flowing into the supply pipe 320 and at the same time, when the valve 554 is opened from the carrier gas supply pipe 550 connected to the gas supply pipe 350 and N ₂ (inert gas) flows, the nozzle It is possible to prevent TiCl ₄ from flowing into 450 or the gas supply pipe 350.

(Residual TiCl ₄ removal: Step S315)
In step S315, residual TiCl ₄ is removed from the processing chamber 201. The valve 338 of the gas supply pipe 330 is closed to stop the supply of TiCl ₄ to the processing chamber 201, and the valve 634 is opened to flow TiCl ₄ to the vent line 630. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove the residual TiCl ₄ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 330, which is a TiCl ₄ supply line, and further from the gas supply pipes 310, 320, 340, and 350 into the processing chamber 201, the residual TiCl _{4 is} further increased. The effect of eliminating is increased.

(O ₃ supply: Step S316)
In step S 316, O ₃ is supplied into the processing chamber 201 from the gas supply pipe 341 of the gas supply system 304. O ₃ is generated using an ozonizer, and the flow rate is adjusted by a mass flow controller 343 and supplied. Before supplying O ₃ to the processing chamber 201, the valve 348 is closed, the valve 644 is opened, and the O ₃ is allowed to flow to the vent line 640 through the valve 644. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 540.

When supplying O ₃ to the processing chamber 201, the valve 644 is closed, the valve 348 is opened, O ₃ is supplied to the gas supply pipe 340 downstream of the valve 348, and the valve 544 is opened. Gas (N ₂ ) is supplied from the carrier gas supply pipe 540. O ₃ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 348 and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 through the nozzle 440. When flowing O ₃ , the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within the range of 30 to 500 Pa, for example, 130 Pa. The supply flow rate of O ₃ controlled by the mass flow controller 343 is 15 slm at a concentration of 250 g / m ³ . The time for exposing the wafer 200 to O ₃ is 60 seconds.

At the same time, when the valve 534 is opened from the carrier gas supply pipe 530 connected to the middle of the gas supply pipe 330 and N ₂ (inert gas) is allowed to flow, O ₃ is introduced into the nozzle 430 and the gas supply pipe 330 on the TiCl ₄ side. It can prevent wrapping around. Similarly, when N ₂ (inert gas) is allowed to flow from the carrier gas supply pipe 510 connected to the middle of the gas supply pipe 310 at the same time to allow N ₂ (inert gas) to flow, O _{3 is} supplied to the nozzle 410 and the gas supply pipe 310 on the TEMAZ side. When the valve 524 is opened from the carrier gas supply pipe 520 connected to the middle of the gas supply pipe 320 and N ₂ (inert gas) is allowed to flow, the nozzle 420 on the TMA side and the gas can be prevented. When O ₃ can be prevented from flowing into the supply pipe 320 and at the same time, when the valve 554 is opened from the carrier gas supply pipe 550 connected to the gas supply pipe 350 and N ₂ (inert gas) flows, the nozzle It is possible to prevent O ₃ from flowing into 450 or the gas supply pipe 350.

By supplying O ₃ , the Ti-containing layer chemically adsorbed on the wafer 200 and the surface of O ₃ react (chemical adsorption), and a titanium oxide film is formed on the wafer 200.

(Residual O ₃ removal: step S317)
In step S317, residual O ₃ is removed from the processing chamber 201. The supply of _{O 3} into the processing chamber 201 by closing the valve 348 of the gas supply pipe 340 is stopped, flow _{O 3} to the vent line 640 by opening the valve 644. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove residual O ₃ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 340 that is an O ₃ supply line and further from the gas supply pipes 310, 320, 330, and 350 into the processing chamber 201, the residual O _{3 is} further increased. The effect of eliminating is increased.

The above steps S314 to S317 are set as one cycle and are performed at least once (step S318), thereby forming a titanium oxide film 36 having a predetermined thickness (40 to 100 mm) on the wafer 200 by using the ALD method (FIG. 5G). reference). In this case, in each cycle, as described above, the atmosphere composed of TiCl ₄ that is the Ti-containing raw material in Step S314 and the atmosphere composed of O ₃ that is the oxidizing gas in Step S316 are processed. Note that the film is formed so as not to mix in the chamber 201.

Thus, the dielectric film 30 composed of the ZrO ₂ film 32, the Al ₂ O ₃ film 34, and the TiO ₂ film 36 is formed.

  After the formation of the dielectric film 30, the process conditions are changed and stabilized, and then the upper electrode forming process is started without removing the wafer 200 on which the dielectric 30 is formed from the processing chamber 201.

(Formation of upper electrode 43 (titanium nitride film 42): Step S112)
With reference to FIGS. 10, 11, and 1 to 3, a film forming process (see step S <b> 112 in FIG. 4, FIG. 5H) of the titanium nitride film 42 that forms the upper electrode 43 will be described.

  When the temperature of the wafer 200 reaches 430 ° C. and the temperature is stabilized (step S401), the next steps are sequentially executed while the temperature in the processing chamber 201 is maintained at 430 ° C.

(TiCl ₄ supply: step S402)
In step S <b> 402, TiCl ₄ is supplied into the processing chamber 201 from the gas supply pipe 331 of the gas supply system 303. Valve 337 is closed and valve 336 is opened. TiCl ₄ is a liquid at normal temperature, and the flow rate of the liquid TiCl ₄ is adjusted by the liquid mass flow controller 333, supplied to the vaporizer 335, and vaporized by the vaporizer 335. Before supplying TiCl ₄ to the processing chamber 201, the valve 338 is closed, the valve 634 is opened, and TiCl ₄ is allowed to flow to the vent line 630 through the valve 634. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 532.

When supplying TiCl ₄ to the processing chamber 201, the valve 634 is closed, the valve 338 is opened, TiCl ₄ is supplied to the gas supply pipe 330 downstream of the valve 338, and the valve 534 is opened to open the carrier. Gas (N ₂ ) is supplied from the carrier gas supply pipe 530. TiCl ₄ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 338 and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 via the nozzle 430. At this time, the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within a range of 20 to 50 Pa, for example, 30 Pa. The supply amount of TiCl ₄ controlled by the liquid mass flow controller 312 is 1.0 to 2.0 g / min. The time for exposing the wafer 200 to TiCl ₄ is 3 to 10 seconds.

At this time, the only gases flowing into the processing chamber 201 are TiCl ₄ and N ₂ that is an inert gas, and NH ₃ does not exist. Therefore, TiCl ₄ does not cause a gas phase reaction, and reacts with the surface of the wafer 200 and the base film (chemical adsorption) to form an adsorption layer or a Ti layer (hereinafter referred to as Ti-containing layer) of the raw material (TiCl ₄ ). Form. The adsorption layer of TiCl ₄ includes a discontinuous adsorption layer as well as a continuous adsorption layer of raw material molecules. The Ti layer includes not only a continuous layer composed of Ti but also a Ti thin film formed by overlapping these layers. In addition, the continuous layer comprised by Ti may be called Ti thin film.

At the same time, when the valve 554 is opened from the carrier gas supply pipe 550 connected to the middle of the gas supply pipe 350 and N ₂ (inert gas) is allowed to flow, TiCl ₄ is transferred to the NH ₃ side nozzle 450 and the gas supply pipe 350. It can prevent wrapping around. Similarly, when N ₂ (inert gas) is flowed from the carrier gas supply pipe 510 connected to the middle of the gas supply pipe 310 at the same time and N ₂ (inert gas) flows, TiCl ₄ wraps around the nozzle 410 and the gas supply pipe 310. When the valve 524 is opened from the carrier gas supply pipe 520 connected to the middle of the gas supply pipe 320 and N ₂ (inert gas) is allowed to flow, TiCl _{4 is} supplied to the nozzle 420 and the gas supply pipe 320. When the valve 544 is opened from the carrier gas supply pipe 540 connected in the middle of the gas supply pipe 340 and N ₂ (inert gas) is allowed to flow, the nozzle 440 and the gas supply pipe 340 can be prevented. TiCl ₄ can be prevented from sneaking around.

(Residual TiCl ₄ removal: Step S403)
In step S 403, residual TiCl ₄ is removed from the processing chamber 201. The valve 338 of the gas supply pipe 330 is closed to stop the supply of TiCl ₄ to the processing chamber 201, and the valve 634 is opened to flow TiCl ₄ to the vent line 630. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove the residual TiCl ₄ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 330, which is a TiCl ₄ supply line, and further from the gas supply pipe 350 and the gas supply pipes 310, 320, and 340 into the processing chamber 201, The effect of eliminating residual TiCl ₄ is enhanced.

(NH ₃ supply: Step S404)
In step S <b> 404, NH ₃ is supplied into the processing chamber 201 from the gas supply pipe 351 of the gas supply system 305. NH ₃ is supplied after its flow rate is adjusted by the mass flow controller 353. Before supplying NH ₃ to the processing chamber 201, the valve 358 is closed, the valve 654 is opened, and NH ₃ is allowed to flow to the vent line 650 through the valve 654. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 550.

When supplying NH ₃ to the processing chamber 201, the valve 654 is closed, the valve 358 is opened, and NH ₃ is supplied to the gas supply pipe 350 downstream of the valve 358, and the valve 554 is opened to open the carrier. Gas (N ₂ ) is supplied from the carrier gas supply pipe 550. NH ₃ merges with the carrier gas (N ₂ ) on the downstream side of the valve 358 and is mixed, and is exhausted from the exhaust pipe 231 while being supplied to the processing chamber 201 via the nozzle 450. When flowing NH ₃ , the APC valve 243 is appropriately adjusted to maintain the pressure in the processing chamber 201 within a range of 50 to 1000 Pa, for example, 60 Pa. The supply flow rate of NH ₃ controlled by the mass flow controller 353 is 1 to 10 slm. The time for exposing the wafer 200 to NH ₃ is 10 to 30 seconds.

At the same time, when the valve 534 is opened from the carrier gas supply pipe 530 connected to the gas supply pipe 330 and N ₂ (inert gas) flows, NH ₃ is introduced into the nozzle 430 and the gas supply pipe 330 on the TiCl ₄ side. It can prevent wrapping around. Similarly, when the valve 514 is opened from the carrier gas supply pipe 510 connected to the gas supply pipe 310 at the same time and N ₂ (inert gas) is allowed to flow, NH ₃ flows into the nozzle 410 and the gas supply pipe 310. When the valve 524 is opened from the carrier gas supply pipe 520 connected to the middle of the gas supply pipe 320 and N ₂ (inert gas) is allowed to flow, NH _{3 is} supplied to the nozzle 420 and the gas supply pipe 320. When the valve 544 is opened from the carrier gas supply pipe 540 connected in the middle of the gas supply pipe 340 and N ₂ (inert gas) is allowed to flow, the nozzle 440 and the gas supply pipe 340 can be prevented. It is possible to prevent NH ₃ from wrapping around.

By supplying NH ₃ , the Ti-containing layer chemically adsorbed on the wafer 200 and NH ₃ undergo a surface reaction (chemical adsorption), and a titanium nitride film is formed on the wafer 200.

(Residual NH ₃ removal: step S405)
In step S405, residual NH ₃ is removed from the processing chamber 201. The supply of the NH ₃ into the processing chamber 201 by closing the valve 358 of the gas supply pipe 350 is stopped, flow NH ₃ to the vent line 650 by opening the valve 654. At this time, the APC valve 243 of the exhaust pipe 231 is kept open, and the inside of the processing chamber 201 is evacuated to 20 Pa or less by the vacuum pump 246 to remove residual NH ₃ from the processing chamber 201. At this time, when an inert gas such as N ₂ is supplied from the gas supply pipe 350 that is an NH ₃ supply line, and further from the gas supply pipe 330 and the gas supply pipes 310, 320, and 340 into the processing chamber 201, The effect of eliminating residual NH ₃ is enhanced.

The above steps S402 to S405 are set as one cycle, and are performed at least once (step S406), thereby forming a titanium nitride film 42 having a predetermined thickness on the wafer 200 by using the ALD method (see FIG. 5H). In this case, in each cycle, as described above, the atmosphere composed of TiCl ₄ that is the Ti-containing material in step S402 and the atmosphere composed of NH ₃ that is the nitriding gas in step S404 are processed. Note that the film is formed so as not to mix in the chamber 201.

When the film forming process for forming the titanium nitride film 42 having a predetermined thickness is performed, the inside of the processing chamber 201 is purged with the inert gas by exhausting while supplying the inert gas such as N ₂ into the processing chamber 201. (Gas purge: Step S407). Thereafter, the atmosphere in the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (return to atmospheric pressure: step S408). Thereafter, the seal cap 219 is lowered by the boat elevator 115, the lower end of the manifold 209 is opened, and the processed wafer 200 is carried out of the processing chamber 201 from the lower end of the manifold 209 while being supported by the boat 217 ( Boat unloading: Step S409). Thereafter, the processed wafer 200 is taken out from the boat 217 (wafer discharge: step S410).

(Gas cleaning: Step S114)
As described above, after the upper electrode 43 is formed and the wafer 200 is taken out of the processing chamber 201, gas cleaning is performed.

  The gas cleaning process (step S114 in FIG. 4) will be described with reference to FIGS.

In the gas cleaning, a cleaning gas is supplied into the processing chamber 201 to remove deposits that are conductive films or insulating films attached to the processing chamber 201, the boat 217, and the like. By using a cleaning gas in which O ₂ is added to BCl ₃ , the ZrO ₂ film, Al ₂ O ₃ film, TiO ₂ film, and TiN film are removed. By performing gas cleaning, cross-contamination between processes can be reduced, and higher productivity can be realized.

To perform gas cleaning, the valve 316 is closed, the valve 317 is opened, BCl ₃ is supplied from the gas supply pipe 312 of the gas supply system 301, the valve 326 is closed, the valve 327 is opened, and the gas supply system 302 BCl ₃ is supplied from the gas supply pipe 322, the valve 336 is closed, the valve 337 is opened, and BCl ₃ is supplied from the gas supply pipe 332 of the gas supply system 303. Further, the valve 346 is closed, the valve 347 is opened, and O ₂ is supplied from the gas supply pipe 342 of the gas supply system 304. Note that the valve 358 of the gas supply system 305 is closed.

The etching gas may be used at a concentration diluted with an inert gas such as N _{2. When} the etching gas BCl ₃ is used after being diluted, the valve 514 is opened and the carrier gas (N ₂ ) is used as the carrier. The gas is supplied from the gas supply pipe 510, the valve 524 is opened, the carrier gas (N ₂ ) is supplied from the carrier gas supply pipe 520, the valve 534 is opened, and the carrier gas (N ₂ ) is supplied from the carrier gas supply pipe 530. To do. When diluting and using O ₂ , the valve 544 is opened and the carrier gas (N ₂ ) is supplied from the carrier gas supply pipe 540. Note that the valve 554 is closed.

To do gas etching, the supply of BCl ₃ and _{O 2} into the processing chamber 201 may be performed continuously, but the exhaust pipe 231 of BCl ₃ and supplied to the processing chamber 201 to the _{O 2} in the processing chamber 201 It is also possible to intermittently (intermittently) exhaust air from That is, cleaning by cycle etching may be performed. Specifically, as shown in FIGS. 12 and 13, the next step S503 to S506 may be set as one cycle, and the cleaning process may be performed by repeating this cycle a predetermined number of times.

In the present embodiment, BCl ₃ and O ₂ are diluted with an inert gas of N ₂ and used for cleaning by cycle etching. Hereinafter, each step will be described.

  When performing gas cleaning, the heater 207 is controlled to keep the inside of the processing chamber 201 at a temperature in the range of, for example, 500 ° C. to 850 ° C. and preferably 550 ° C.

  Thereafter, the boat 217 without the wafer 200 is lifted by the boat elevator 115 and loaded into the processing chamber 201 (boat loading) (step S501). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220.

  Thereafter, when the temperature in the processing chamber 201 reaches 550 ° C. and the temperature is stabilized (step S502), the next steps are sequentially executed while the temperature in the processing chamber 201 is maintained at 550 ° C.

(Evacuation: step S503)
First, with the valves 318, 328, 338, 348, 358, 514, 524, 534, 544 and 554 closed, the APC valve 243 is opened and the inside of the processing chamber 201 is evacuated. After the pressure in the processing chamber 201 reaches the first pressure, the APC valve 243 is closed. Thereby, the inside of the processing chamber 201 is sealed.

In the gas supply system 301, the valve 317 is opened, and the flow rate of BCl ₃ is adjusted by the mass flow controller 314 and flows into the gas supply pipe 312. However, before the supply to the processing chamber 201, the valve 318 is closed and the valve 614 is opened. Then, BCl ₃ is allowed to flow through the vent line 610 through the valve 614. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 512.

In the gas supply system 302, the valve 327 is opened and the flow rate of BCl ₃ is adjusted by the mass flow controller 324 to flow into the gas supply pipe 322. However, before the supply to the processing chamber 201, the valve 328 is closed and the valve 624 is opened. Then, BCl ₃ is allowed to flow through the vent line 620 through the valve 624. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 522.

In the gas supply system 303, the valve 337 is opened, and the flow rate of BCl ₃ is adjusted by the mass flow controller 334 to flow into the gas supply pipe 332, but before the supply to the processing chamber 201, the valve 338 is closed and the valve 634 is opened. Then, BCl ₃ is allowed to flow through the vent line 630 through the valve 634. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 532.

In the gas supply system 304, the valve 347 is opened and the flow rate of O ₂ is adjusted by the mass flow controller 344 and flows into the gas supply pipe 342. Before the gas is supplied to the processing chamber 201, the valve 348 is closed and the valve 644 is opened. Then, O ₂ is allowed to flow through the valve 644 to the vent line 640. On the other hand, the flow rate of N ₂ as the carrier gas is adjusted by the mass flow controller 542.

(BCl ₃ and O ₂ supply: step S504)
BCl ₃ and O ₂ are supplied into the processing chamber 201 in a state where the APC valve 243 is closed and the pressure in the processing chamber 201 becomes the first pressure described later. The supply is performed as follows.

The valve 614 is closed and the valve 318 is opened to supply BCl ₃ to the gas supply pipe 310 downstream of the valve 318 and the valve 514 is opened to supply the carrier gas (N ₂ ) from the carrier gas supply pipe 510. The BCl ₃ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 318 and supplied to the processing chamber 201 through the nozzle 410.

The valve 624 is closed and the valve 328 is opened to supply BCl ₃ to the gas supply pipe 320 downstream of the valve 328 and the valve 524 is opened to supply the carrier gas (N ₂ ) from the carrier gas supply pipe 520. BCl ₃ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 328, and supplied to the processing chamber 201 through the nozzle 420.

The valve 634 is closed, the valve 338 is opened, BCl ₃ is supplied to the gas supply pipe 330 downstream of the valve 338, and the valve 534 is opened to supply the carrier gas (N ₂ ) from the carrier gas supply pipe 530. The BCl ₃ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 338 and supplied to the processing chamber 201 through the nozzle 430.

The valve 644 is closed and the valve 348 is opened to supply O ₂ to the gas supply pipe 340 downstream of the valve 348 and the valve 544 is opened to supply the carrier gas (N ₂ ) from the carrier gas supply pipe 540. O ₂ is mixed and mixed with the carrier gas (N ₂ ) on the downstream side of the valve 348 and supplied to the processing chamber 201 via the nozzle 440.

(BCl ₃ and O ₂ containment: step S505)
In this way, BCl ₃ and O ₂ and the carrier gas (N ₂ ) are supplied into the processing chamber 201, and the valves 318, 328, 338, 348 are formed when the pressure in the processing chamber 201 becomes the second pressure described later. 514, 524, 534 and 544 are closed, and supply of BCl ₃ and O ₂ and carrier gas (N ₂ ) into the processing chamber 201 is stopped. Thereby, the gas supply system is sealed. At this time, all the valves directly connected to the processing chamber 201 are closed. That is, the gas supply system and the exhaust system are both sealed. As a result, the inside of the processing chamber 201 is sealed, and BCl ₃ and O ₂ are sealed in the processing chamber 201. Then, this state, that is, the inside of the processing chamber 201 is sealed by sealing the gas supply system and the exhaust system, and the state in which BCl ₃ and O ₂ are sealed in the processing chamber 201 is maintained for a predetermined time.

When the supply of BCl ₃ into the processing chamber 201 is stopped by closing the valves 318, 328, 338, 348, the valves 614, 624, 634 are opened and the BCl ₃ is allowed to flow through the vent lines 610, 620, 630, and the valve 644 is opened. And allow O ₂ to flow through the vent line 640.

(Gas removal: Step S506)
After a predetermined time has elapsed since BCl ₃ and O ₂ were sealed in the processing chamber 201, the APC valve 243 is opened and the processing chamber 201 is evacuated through the exhaust pipe 231. Thereafter, the valves 514, 524, 534, and 544 are opened, and an exhaust gas is exhausted from the exhaust pipe 231 while supplying the N ₂ inert gas into the process chamber 201, and the gas in the process chamber 201 is purged.

  The above steps S503 to S506 are set as one cycle, and this cycle is repeated a predetermined number of times (step S507) to perform cleaning by cycle etching. Thus, during cleaning, the step of closing the APC valve 243 for a predetermined time and the step of opening the APC valve 243 for a predetermined time are repeated a predetermined number of times. That is, the opening and closing of the APC valve 243 is repeated a predetermined number of times intermittently (intermittently). According to cleaning by cycle etching, the etching amount can be controlled by the number of cycles by confirming the etching amount per cycle. In addition, the amount of gas consumption can be reduced as compared with a method of cleaning by flowing an etching gas continuously.

BCl ₃ and O ₂ introduced into the processing chamber 201 are diffused throughout the processing chamber 201, and ZrO ₂ film and Al ₂ O ₃ film adhered to the processing chamber 201, that is, the inner wall of the reaction tube 203 and the boat 217. , A TiO ₂ film and a TiN film, a thermal chemical reaction occurs, and a reaction product having a high vapor pressure is generated. The generated reaction product is exhausted from the exhaust pipe 231 to the outside of the processing chamber 201. The In this way, the processing chamber 201 is cleaned.

When the above cycle is performed a preset number of times, the inside of the processing chamber 201 is evacuated, and then the processing chamber 201 is evacuated while supplying an inert gas such as N ₂ to purge the inside of the processing chamber 201. (Purge: Step S508). After purging the inside of the processing chamber 201, the inside of the processing chamber 201 is replaced with an inert gas such as N _{2 and} the pressure in the processing chamber 201 is returned to atmospheric pressure (return to atmospheric pressure: step S509). Thereafter, the seal cap 219 is lowered by the boat elevator 115 to open the lower end of the manifold 209, and the boat 217 is carried out of the processing chamber 201 from the lower end of the manifold 209 (boat unloading: step S510).

In addition, as the processing conditions of the cleaning by the cycle etching,
First pressure: 1.33 to 13300 Pa,
Second pressure: 13.3 to 66500 Pa, preferably 13300 to 26600 Pa,
BCl ₃ supply flow rate: 0.5-5 slm,
O ₂ supply flow rate: 0.01 to 0.1 slm,
BCl ₃ and O ₂ gas supply time (transition time): 0.1 to 15 min,
BCl ₃ and O ₂ gas encapsulation time (encapsulation time): 0.1 to 15 min,
Exhaust time: 0.1 to 10 min,
Number of cycles: 1 to 100 times
The cleaning is performed by keeping each cleaning condition constant at a certain value within each range.

In the present embodiment, the lower electrode 23 made of the TiN film 22, the dielectric film 30 made of the ZrO ₂ film 32, the Al ₂ O ₃ film 34 and the TiO ₂ film 36, and the upper electrode 43 made of the TiN film 42 are formed on the same substrate. Since the processing apparatus 101 is used, a capacitor used in the semiconductor device can be efficiently performed with a small occupied floor area. Also, by sharing the apparatus, it is possible to share spare parts, and the apparatus operating cost can be reduced.

Further, the substrate processing apparatus 101 of the present embodiment includes a processing chamber 201 that accommodates the wafer 200, a raw material supply system 301 that supplies a raw material (TEMAZ) containing Zr to the processing chamber 201, and an Al in the processing chamber 201. A raw material supply system 302 that supplies a raw material (TMA) containing oxygen, a raw material supply system 303 that supplies a raw material (TiCl ₄ ) containing Ti to the processing chamber 201, and O ₃ that is an oxidizing agent is supplied to the processing chamber 201. An oxidant supply system 304, a processing chamber 201, a nitriding agent supply system 305 for supplying NH ₃ as a nitriding agent, and a controller 280. The controller 280 supplies TEMAZ and O ₃ to the processing chamber 201. after forming the ZrO ₂ film 32 is supplied alternately by alternately supplying TMA and _{O 3} into the processing chamber 201 to form an _Al 2 _{O 3} film 34, the TiCl ₄ and _{O 3} into the processing chamber 201 A dielectric film 30 having a ZrO ₂ film 32, _Al 2 _{O 3} film 34 and the TiO ₂ film 36 by forming the TiO ₂ film 36 is formed on the wafer 200 to each other supplied with TiCl ₄ and NH ₃ The raw material supply system 301, the raw material supply system 302, the raw material supply system 303, the oxidant supply system 304 and the nitriding agent supply system 305 are controlled so that the upper electrode 43 made of the TiN film 42 is formed by being alternately supplied to the processing chamber 201. is doing.

Accordingly, the dielectric film 30 composed of the ZrO ₂ film 32, the Al ₂ O ₃ film 34 and the TiO ₂ film 36, and the upper electrode 43 composed of the TiN film 42 can be formed by the same substrate processing apparatus 101, and the capacitor used in the semiconductor device Can be carried out efficiently and with a small occupied floor area. Also, by sharing the apparatus, it is possible to share spare parts, and the apparatus operating cost can be reduced.

In this embodiment, TEMAZ and O ₃ are alternately supplied to the processing chamber 201 to form the ZrO ₂ film 32, and TMA and O ₃ are alternately supplied to the processing chamber 201 to obtain the Al ₂ O ₃ film 34. TiCl ₄ and O ₃ are alternately supplied to the processing chamber 201 to form the TiO ₂ film 36 to form the dielectric film 30, and TiCl ₄ and NH ₃ are alternately supplied to the processing chamber 201. Since the upper electrode 43 made of the TiN film 42 is formed, a uniform dielectric film or electrode film is covered even if the capacitor structure has a three-dimensional shape such as a cylinder and a reduced shape. It can be formed well.

Further, TiCl ₄ and O ₃ are alternately supplied to the processing chamber 201 to form a TiO ₂ film 36 as an upper layer of the three-layer dielectric film 30, and TiCl ₄ and NH ₃ are alternately supplied to the processing chamber 201 to form TiN. Since the upper electrode 43 made of the film 42 is formed, the upper electrode 43 made of the TiN film 42 can be continuously formed after the formation of the TiO ₂ film 36. That is, without removing the boat 217 loaded with the wafers 200 from the processing chamber 201, the temperature of the processing chamber 201 is changed and the gas type is changed while the boat 217 loaded with the wafers 200 is inserted into the same processing chamber 201. Thus, since the upper electrode 43 made of the TiN film 42 can be continuously formed after the TiO ₂ film 36 is formed, the time can be significantly reduced.

  FIG. 14 shows a case where the formation of the dielectric film 30 and the formation of the TiN film 42 for the upper electrode 43 are performed continuously without removing the boat 217 loaded with the wafers 200 from the processing chamber 201 (continuous). In this case, after forming the dielectric film 30, the boat 217 carrying the wafers 200 is taken out from the processing chamber 201, the wafers 200 are unloaded from the boat 217, and the wafers 200 are transferred to another processing apparatus. When the wafer 200 is mounted on a boat by another processing apparatus, and the boat on which the wafer 200 is mounted is loaded into a processing chamber of another processing apparatus to form the TiN film 42 for the upper electrode 43 (separate cases) ) Is schematically shown.

  As shown in FIG. 14, the formation of the dielectric film 30 and the formation of the TiN film 42 for the upper electrode 43 are continuously processed, so that the pre-processing time in different cases (substrate loading, boat insertion, vacuum drawing, Such as temperature stabilization), post-processing time (nitrogen purge, boat removal, substrate cooling, substrate unloading), transport time of processed substrate and processing waiting time are replaced by continuous gas replacement time, greatly reducing time Is possible.

Further, TiCl ₄ and O ₃ are alternately supplied to the processing chamber 201 to form a TiO ₂ film 36 as an upper layer of the three-layer dielectric film 30, and TiCl ₄ and NH ₃ are alternately supplied to the processing chamber 201 to form TiN. Since the upper electrode 43 made of the film 42 is formed, Ti supply piping can be supplied, and the configuration of the apparatus is simplified correspondingly.

In the above embodiment, as shown in FIG. 4, the ZrO ₂ film 32 is formed (Step S106), the Al ₂ O ₃ film 34 is formed (Step S108), and the TiO ₂ film 36 is formed (Step S110). Thereafter, the upper electrode 43 made of the TiN film 42 is continuously formed (step S112), and then the gas cleaning (step S114) is performed to form the ZrO ₂ film, the Al ₂ O ₃ film, the TiO ₂ film, and the TiN film. by removing has been reduced cross-contamination between processes, as shown in FIG. 15, the formation of ZrO ₂ film 32 (step S106), the formation of the _Al 2 _{O 3} film 34 (step S108), TiO ₂ After the formation of the film 36 (step S110) to form the dielectric film 30, gas cleaning (step S111) is performed, and then TiN 42 an electrode 43 is formed on consisting (step S112), the subsequent performing gas cleaning (step S114), the dielectric film 30 (ZrO ₂ film, _Al 2 _{O 3} film, TiO ₂ film) formed with the upper electrode 43 Cross contamination during the formation of (TiN film) can be more effectively reduced.

Further, as shown in FIG. 16, gas cleaning (step S107) is performed between the formation of the ZrO ₂ film 32 (step S106) and the formation of the Al ₂ O ₃ film 34 (step S108) to obtain an Al ₂ O ₃ film. When gas cleaning (step S109) is also performed between the formation of step 34 (step S108) and the formation of the TiO ₂ film 36 (step S110), formation of the ZrO ₂ film 32 constituting the dielectric film 30 and Al ₂ O Cross-contamination between the formation of the _three films 34 and the formation of the TiO ₂ film 36 can be more effectively reduced.

  In the above embodiment, after forming the lower electrode 23, the wafer 200 is discharged from the processing chamber 201. However, when the lower electrode 23 is not processed to form the cylinder hole 20 or the like as shown in FIG. 5F, The process conditions may be changed as they are without discharging the wafer 200 from the processing chamber 201 and the process for forming the dielectric film 30 (steps S106, S108, and S110 in FIG. 4) may be entered.

In the above embodiment, as the titanium-containing raw material, but using titanium tetrachloride (TiCl _4), in place of the titanium tetrachloride (TiCl _4), tetrakis-dimethylamino titanium _{(TDMAT, Ti [N (CH} 3) 2] ₄ ), tetrakisdiethylaminotitanium (TDEAT, Ti [N (CH ₂ CH ₃ ) ₂ ] ₄ ) and the like.

In the above embodiment, tetrakisethylmethylaminozirconium (TEMAZ, Zr (NEtMe) ₄ ) is used as the zirconium-containing raw material, but Zr (O-tBu) ₄ , Zr (NMe ₂ ) is used instead of TEMAZ. ₄ , Zr (NEt ₂ ) ₄ , Zr (MMP) ₄ or the like.

In the above embodiment, trimethylaluminum (TMA, Al (CH ₃ ) ₃ ) is used as the aluminum-containing raw material, but aluminum chloride (AlCl ₃ ) or the like may be used instead of TMA.

In the above embodiment, as the oxidizing agent, but using _{O 3,} in place of _{O 3, O 2, NO,} O 3, H 2 O, may be used H 2 + _{O 2} or the like.

In the above embodiment, ammonia (NH ₃ ) is used as the nitriding agent. However, instead of ammonia, nitrogen (N ₂ ), nitrous oxide (N ₂ O), monomethylhydrazine (CH ₆ N ₂ ) Etc. may be used.

In the above embodiment, BCl ₃ is used as the cleaning gas, but BBr ₃ , BI _3, etc. may be used instead of BCl ₃ .

In the above embodiment, N ₂ (nitrogen) is used as the carrier gas, but He (helium), Ne (neon), Ar (argon), or the like may be used instead of nitrogen.

In the above embodiment, O ₂ is added to BCl ₃ in the cleaning gas. However, it is better to add O ₂ to clean the zirconium oxide film, the aluminum oxide film, and the titanium oxide film. The film can be removed by cleaning without adding O ₂ .

  In the above embodiment, the vaporizers 315, 325, and 335 are used to vaporize the liquid raw material, but a bubbler may be used instead of the vaporizer.

(Preferred embodiment of the present invention)
Hereinafter, preferred embodiments of the present invention will be additionally described.

(Appendix 1)
According to a preferred aspect of the present invention,
Forming a lower electrode on the substrate;
Forming a dielectric film by laminating three kinds of metal oxide films each containing a different metal element on the lower electrode;
Forming an upper electrode on the dielectric film;
There is provided a method for manufacturing a semiconductor device in which the steps are performed by the same apparatus.

(Appendix 2)
The method for manufacturing a semiconductor device according to appendix 1, wherein each step is preferably performed in the same processing chamber.

(Appendix 3)
The method for manufacturing a semiconductor device according to appendix 1 or 2, wherein the step of forming the dielectric film and the step of forming the upper electrode are preferably performed successively.

(Appendix 4)
The method for manufacturing a semiconductor device according to appendix 3, preferably, after the step of forming the dielectric film, the substrate on which the dielectric film is formed is taken out from the processing chamber used in the step of forming the dielectric film. The process of forming the said upper electrode is performed with it inserted without any change.

(Appendix 5)
A method of manufacturing a semiconductor device according to any one of appendices 1 to 4, preferably,
The step of forming the dielectric film includes
Forming the first metal oxide film by alternately supplying the first raw material containing the first metal element to the processing chamber containing the substrate and supplying the oxidizing agent to the processing chamber;
Supplying a second raw material containing a second metal element different from the first metal element to the processing chamber containing the substrate and supplying the oxidizing agent to the processing chamber alternately are performed. Forming a metal oxide film 2;
Supply of the third raw material containing the first metal element and the third metal element different from the second metal element to the processing chamber containing the substrate, and supply of the oxidizing agent to the processing chamber And alternately forming a third metal oxide film, and
The step of forming an upper electrode on the dielectric film includes:
Forming a metal nitride film by alternately supplying a fourth raw material containing a fourth metal element to the processing chamber containing the substrate and supplying a nitriding agent to the processing chamber.

(Appendix 6)
The method for manufacturing a semiconductor device according to appendix 5, wherein the third metal element and the fourth metal element are preferably the same.

(Appendix 7)
The method for manufacturing a semiconductor device according to appendix 6, wherein the third raw material and the fourth raw material are preferably the same.

(Appendix 8)
The method for manufacturing a semiconductor device according to appendix 7, wherein the third raw material and the fourth raw material are preferably supplied from the same raw material supply system.

(Appendix 9)
The method for manufacturing a semiconductor device according to any one of appendices 6 to 8, preferably, the third metal element and the fourth metal element are titanium.

(Appendix 10)
The method for manufacturing a semiconductor device according to appendix 5, wherein the first metal element is preferably zirconium, the second metal element is aluminum, and the third metal element and the fourth metal element are titanium. It is.

(Appendix 11)
The method of manufacturing a semiconductor device according to appendix 10, wherein the first metal oxide film is preferably a zirconium oxide film, the second metal oxide film is an aluminum oxide film, and the third metal oxide film is oxidized. It is a titanium film, and the metal nitride film is a titanium nitride film.

(Appendix 12)
The method for manufacturing a semiconductor device according to any one of appendices 5 to 11, wherein the third material and the fourth material are preferably TiCl ₄ .

(Appendix 13)
The method for manufacturing a semiconductor device according to any one of appendices 5 to 12, wherein the oxidant is preferably O ₃ .

(Appendix 14)
The method for manufacturing a semiconductor device according to any one of appendices 5 to 13, wherein the nitriding agent is preferably NH ₃ .

(Appendix 15)
The method of manufacturing a semiconductor device according to any one of appendices 1 to 4, wherein the lower electrode and the upper electrode are titanium nitride films, and the three metal oxide films constituting the dielectric film are zirconium oxide films An aluminum oxide film and a titanium oxide film.

(Appendix 16)
The method of manufacturing a semiconductor device according to any one of appendices 1 to 15, wherein gas cleaning is preferably performed after the dielectric film and the upper electrode are formed.

(Appendix 17)
In the method of manufacturing a semiconductor device according to any one of appendices 1 to 16, preferably, after the dielectric film is formed, gas cleaning is performed before the step of forming the upper electrode.

(Appendix 18)
The method of manufacturing a semiconductor device according to any one of appendices 1 to 16, preferably, when forming the dielectric film, gas cleaning is performed each time each metal oxide film is formed.

(Appendix 19)
According to another preferred aspect of the invention,
A processing chamber for accommodating the substrate;
A first raw material supply system for supplying a first raw material containing a first metal element to the processing chamber;
A second raw material supply system for supplying a second raw material containing a second metal element different from the first metal element to the processing chamber;
A third raw material supply system for supplying a third raw material containing a third metal element different from the first metal element and the second metal element to the processing chamber;
An oxidizing agent supply system for supplying an oxidizing agent to the processing chamber;
A nitriding agent supply system for supplying a nitriding agent to the processing chamber;
The first raw material and the oxidizing agent are alternately supplied to the processing chamber to form a first metal oxide film, and then the second raw material and the oxidizing agent are processed on the first metal oxide film. A second metal oxide film is formed by alternately supplying to the chamber, and a third metal oxide film is formed by alternately supplying the third raw material and the oxidizing agent to the processing chamber on the second metal oxide film. A dielectric film having the first metal oxide film, the second metal oxide film, and the third metal oxide film is formed on the substrate by forming a film, and the third raw material and the nitriding agent are formed. The first raw material supply system, the second raw material supply system, the third raw material supply system, and the oxidant supply so as to form an upper electrode on the dielectric film by alternately supplying the gas to the processing chamber A control unit for controlling the system and the nitriding agent supply system;
A substrate processing apparatus is provided.

(Appendix 20)
According to still another preferred aspect of the present invention,
Forming a metal nitride film of a capacitor lower electrode on the surface of the object to be processed;
Forming a dielectric film on the metal nitride film of the lower electrode;
There is provided a film forming method for forming a metal nitride film of an upper electrode for a capacitor on the dielectric film in a processing container of the same semiconductor manufacturing apparatus.

(Appendix 21)
The film forming method according to appendix 20, preferably, the step of forming the dielectric film and the step of forming the metal nitride film of the capacitor upper electrode are continuously performed in a processing container of the same semiconductor manufacturing apparatus. .

(Appendix 22)
The film forming method according to appendix 20 or 21, wherein the metal nitride film of the upper electrode for a capacitor is preferably formed by alternately treating a metal raw material containing a metal and a nitrogen-containing reducing agent in the metal nitride film of the upper electrode. The dielectric film is formed by supplying a metal material containing a metal constituting the dielectric film and an oxidizing agent alternately into the processing container.

(Appendix 23)
The film forming method according to appendix 22, wherein the metal raw material containing metal of the metal nitride film of the upper electrode is preferably TiCl ₄ and the nitrogen-containing reducing agent is NH ₃ .

(Appendix 24)
The film forming method according to appendix 22 or 23, wherein the metal raw material including the metal constituting the dielectric film is TiCl ₄ , and the oxidizing agent is O ₃ or H ₂ O.

  While various typical embodiments of the present invention have been described above, the present invention is not limited to these embodiments. Accordingly, the scope of the invention is limited only by the following claims.

20 Cylinder hole 22, 42 Titanium nitride film (TiN film)
23 Lower electrode 30 Dielectric film 32 ZrO ₂ film 34 Al ₂ O ₃ film 36 TiO ₂ film 43 Upper electrode 101 Substrate processing apparatus 115 Boat elevator 200 Wafer 201 Processing chamber 202 Processing furnace 203 Reaction tube 207 Heater 209 Manifold 217 Boat 218 Boat Support base 219 Seal cap 231, 232 Exhaust pipe 243 APC valve 245 Pressure sensor 246 Vacuum pump 250 Power supply 263 Temperature sensor 267 Rotating mechanism 280 Controller 301, 302, 303, 304, 305 Gas supply system 310, 311, 312, 320 , 312, 322, 330, 331, 332, 340, 341, 342, 350, 351 Gas supply pipes 313, 314, 323, 324, 333, 334, 343, 344, 353, 512, 522, 532, 5 2,552 Mass flow controller 313, 323, 333 Liquid mass flow controller 315, 325, 335 Vaporizer 316, 317, 318, 326, 327, 328, 336, 337, 336, 346, 347, 348, 358, 514, 524, 534, 544, 554, 614, 624, 634, 644, 654 Valve 410, 420, 430, 440, 450 Nozzle 410a, 420a, 430a, 440a, 450a Gas supply hole 510, 520, 530, 540, 550 Carrier gas supply Pipe 610, 620, 630, 640, 650 Vent line

Claims (5)

Forming a lower electrode on the substrate;
Forming a dielectric film by laminating three kinds of metal oxide films each containing a different metal element on the lower electrode;
Forming an upper electrode on the dielectric film;
A method of manufacturing a semiconductor device, wherein each step is performed by the same device.   The method of manufacturing a semiconductor device according to claim 1, wherein the step of forming the dielectric film and the step of forming the upper electrode are performed continuously.   3. The semiconductor device according to claim 1, wherein the lower electrode and the upper electrode are titanium nitride films, and the three types of metal oxide films constituting the dielectric film are a zirconium oxide film, an aluminum oxide film, and a titanium oxide film. Production method.   4. The method of manufacturing a semiconductor device according to claim 1, wherein, when forming the dielectric film, gas cleaning is performed each time each metal oxide film is formed. 5. A processing chamber for accommodating the substrate;
A first raw material supply system for supplying a first raw material containing a first metal element to the processing chamber;
A second raw material supply system for supplying a second raw material containing a second metal element different from the first metal element to the processing chamber;
A third raw material supply system for supplying a third raw material containing a third metal element different from the first metal element and the second metal element to the processing chamber;
An oxidizing agent supply system for supplying an oxidizing agent to the processing chamber;
A nitriding agent supply system for supplying a nitriding agent to the processing chamber;
The first raw material and the oxidizing agent are alternately supplied to the processing chamber to form a first metal oxide film, and then the second raw material and the oxidizing agent are processed on the first metal oxide film. A second metal oxide film is formed by alternately supplying to the chamber, and a third metal oxide film is formed by alternately supplying the third raw material and the oxidizing agent to the processing chamber on the second metal oxide film. A dielectric film having the first metal oxide film, the second metal oxide film, and the third metal oxide film is formed on the substrate by forming a film, and the third raw material and the nitriding agent are formed. The first raw material supply system, the second raw material supply system, the third raw material supply system, and the oxidant supply so as to form an upper electrode on the dielectric film by alternately supplying the gas to the processing chamber A control unit for controlling the system and the nitriding agent supply system;
A substrate processing apparatus.