JP3515963B2 - Substrate processing equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment apparatus for heat treating a substrate such as a semiconductor wafer in a semiconductor device manufacturing process.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process,
For example, SOD (Spin on Dielectric)
c) The system forms an interlayer insulating film. This S
In the OD system, a coating film is spin-coated on a wafer and subjected to chemical treatment or heat treatment to form an interlayer insulating film.

When forming an interlayer insulating film by, for example, the sol-gel method, first, a colloid of an insulating film material, for example, TEOS (tetraethoxysilane) is placed on a semiconductor wafer (hereinafter referred to as "wafer") as an organic solvent. The solution dispersed in is supplied. Next, the wafer supplied with the solution is subjected to gelation treatment, and then the solvent is replaced. Then, the wafer in which the solvent is replaced is heat-treated.

The heat treatment unit for performing this heat treatment is
It has a heating plate arranged above the unit body for heating the wafer, and a chamber for covering the heating plate during the wafer heating process to form a wafer heating process space. This chamber has a means for introducing an inert gas therein, and at the time of heat treatment, the chamber is lowered to cover the hot plate while introducing, for example, nitrogen gas in order to prevent wafer oxidation. .

[0005]

However, since the surface of the hot plate is exposed at substantially the same height as the upper part of the unit body, when the chamber is lowered while introducing nitrogen gas, the chamber and the hot plate are pressed by the gas pressure. The gas flows out from the gap between and and is scattered. As a result, for example, particles may be generated in a transfer device that transfers the substrate, another processing unit, or the like, which may adversely affect the entire process.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a substrate processing apparatus which does not scatter gas to the outside when the lid is moved up and down.

[0007]

In order to achieve the above object, the present invention provides a hot plate on which heat treatment is applied to a substrate, a periphery of the hot plate, and an upper end portion of which has a surface height substantially equal to that of the hot plate. A casing having a cover provided at the same height and having an exhaust port for exhausting the gas inside, and arranged so as to be able to move up and down on the hot plate, covering the hot plate in a lowered position and from the height of the cover surface. And a lid whose lower end is arranged at a lower position.

According to this structure, the lower end of the lid at the lower position of the lid is arranged at a position lower than the height of the cover surface, so that the inside of the space covered by the lid and the heat plate is closed. The gas can be exhausted into the casing and does not leak outside the device. Therefore, it is possible to prevent the generation of particles and prevent adverse effects on other processing devices and the like.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 show an S according to an embodiment of the present invention.
It is a figure which shows the whole structure of OD system, FIG. 1 is a top view, FIG. 2 is a front view, and FIG. 3 is a rear view.

In this SOD system 1, a plurality of semiconductor wafers (hereinafter referred to as wafers) W as substrates are loaded into or unloaded from the system by a plurality of wafer cassettes CR, for example, in units of 25 wafers. A cassette block 10 for loading / unloading the wafer W to / from the CR, and a single wafer type processing station for performing a predetermined process on the wafer W one by one in the SOD coating process are arranged in multiple stages at predetermined positions. Processing block 11
And a cabinet 12 in which a bottle of ammonia water, a bubbler, a drain bottle, etc., which are required in the aging process, are integrally connected.

In the cassette block 10, as shown in FIG. 1, a plurality of wafer cassettes CR, for example, up to four wafer cassettes CR are provided at the positions of the projections 20a on the cassette mounting table 20, with their respective wafer entrances / outlets directed toward the processing block 11 side. A wafer carrier 21 that is placed in a line in the direction and is movable in the cassette arrangement direction (X direction) and in the wafer arrangement direction (Z vertical direction) of the wafers stored in the wafer cassette CR is selectively provided in each wafer cassette CR. It is designed to be accessed. Further, the wafer carrier 21 is configured to be rotatable in the θ direction, and the processing block 11 will be described later.
The transfer / cooling plate (TCP) belonging to the multi-stage station section of the third group G3 on the side can also be accessed.

In the processing block 11, as shown in FIG. 1, a vertical transfer type main wafer transfer mechanism 22 is provided at the center, and all the processing stations are surrounded by one or a plurality of stages. It is located in. In this example,
It is a multistage arrangement configuration of four sets G1, G2, G3, G4, and
And the multi-stage stations of the second group G1 and G2 are juxtaposed on the front side of the system (front side in FIG. 1),
The multi-tier station of No. 3 is located adjacent to the cassette block 10, and the multi-tier station of the fourth set G4 is located adjacent to the cabinet 12.

As shown in FIG. 2, in the first set G1, the wafer W is placed on the spin chuck in the cup CP, the insulating film material is supplied, and the wafer is rotated to form a uniform insulating film on the wafer. The SOD coating processing station (SCT) for coating and the wafer W placed on the spin chuck in the cup CP are supplied with exchange chemicals such as HMDS and heptane, and the solvent in the insulating film coated on the wafer is dried before the drying step. And a solvent exchange processing station (DSE) that performs processing for replacing with another solvent are stacked in two stages in order from the bottom.

In the second group G2, the SOD coating processing station (SCT) is arranged in the upper stage. It is also possible to arrange an SOD coating processing station (SCT), a solvent exchange processing station (DSE) or the like below the second group G2, if necessary.

As shown in FIG. 3, in the third group G3, 2
A low oxygen high temperature heat treatment station (OHP), a low temperature heat treatment station (LHP), two cooling treatment stations (CPL), a transfer / cooling plate (TCP), and a cooling treatment station (CPL). They are arranged in multiple stages from the top. The low temperature heat treatment station (LHP) has a hot plate on which the wafer W is placed, and heats the wafer W at low temperature. Cooling station (C
PL) has a cooling plate on which the wafer W is placed.
Is cooled. The transfer / cooling plate (TCP) has a two-stage structure having a cooling plate for cooling the wafer W in the lower stage and a transfer table in the upper stage, and transfers the wafer W between the cassette block 10 and the processing block 11.

In the fourth group G4, there are two low temperature heat treatment stations (LHP), two low oxygen curing / cooling treatment stations (DCC), and an aging treatment station (DA).
C) and are arranged in multiple stages in order from the top. The low oxygen curing / cooling processing station (DCC) has a hot plate and a cooling plate adjacent to each other in a process chamber capable of being sealed, and is subjected to high temperature heat treatment and heat treatment in a low oxygen atmosphere substituted with N2. The wafer W is cooled. The aging processing station (DAC) has NH3 inside the processing chamber that can be hermetically sealed.
+ H2O is introduced and the wafer W is subjected to an aging treatment to wet-gel the insulating film material film on the wafer W.

Referring to FIG. 3, the main wafer transfer mechanism 22 is equipped with a wafer transfer device 30 which is vertically movable (Z direction) inside the cylindrical support 27. Cylindrical support 2
Reference numeral 7 is connected to a rotary shaft of a motor (not shown), and is rotated integrally with the wafer transfer device 30 about the rotary shaft by the rotational driving force of the motor. Therefore, the wafer transfer device 30 is rotatable in the θ direction. For example, three tweezers are provided on the transfer base 40 of the wafer transfer device 30, and these tweezers 31 access the processing stations arranged around the main wafer transfer mechanism 22 to communicate with these processing stations. The wafer W is transferred between them.

Next, the low oxygen high temperature heat treatment station (OHP) according to the present invention will be described. 4 and 5
FIG. 3A is a plan view and a cross-sectional view of a low oxygen high temperature heat treatment station (OHP). In this low oxygen high temperature heat treatment station (OHP), a casing 19 having an open upper portion is covered with a cover 19, and a circular opening 19a of the cover 19 is provided with a treatment chamber 51. There is. The processing chamber 51 includes a support body 24 that supports the hot plate 23 shown in FIG. 6, and a lid body 15 that is arranged to be movable up and down with respect to the support body 24. A partition plate 38 is provided in the space surrounded by the casing 18 and the cover 19, and the partition plate 38 allows an exhaust space S and a space V to be described later.
Is formed. Two elevating cylinders 54 and 55 are arranged in this space V, and the elevating cylinder 54 is connected to the lid body 15 via a support member 56.
5 is driven up and down. On the other hand, the elevating cylinder 55 is connected to three elevating pins 58 via a support member 57 to drive the elevating pins 58 up and down.

As shown in FIG. 6, a heating plate 23 is arranged in the approximate center of the support 24. A heater (not shown) is built in the heating plate 23, for example, 200 ° C.
It is designed to be heated to ~ 800 ° C. Further, for example, three holes 43 are penetrated from the front surface to the back surface of the support 24 and the heat plate 23. The elevating pins 58 described above are arranged in each hole 43 so as to be retractable from the surface of the heating plate 23. The elevating pins 58 project from the surface of the heating plate 23 and the wafer W with the main wafer transfer mechanism 22.
To deliver. Wafer W from main wafer transfer mechanism 22
The elevating pin 58 that has received is lowered and is immersed in the hot plate 23, whereby the wafer W is placed on the hot plate 23 and the wafer W is heated.

Although not shown, the wafer W is attached to the hot plate 23.
Proximity sheets for floating and holding the hot plate 23 without adhering to the top are arranged at a plurality of positions, for example, 6 positions, on the outer peripheral portion of the wafer W mounting position on the surface of the heat plate 23.

Referring to FIG. 7, the surface of the cover 19 and the heating plate 2
All three surfaces and the surface of the support 24 are arranged at substantially the same height. A recess 24a having an O-ring 45 is provided on the peripheral edge of the support 24 as shown in the drawing, while the cover 1
5 is fitted in the recess 24a at the peripheral edge of the recess 24.
A flange portion 15a having substantially the same height as the depth of a is provided. As a result, as shown in FIG.
The heating chamber R is formed by the lower end of the flange portion 15a of the lid 15 being in close contact with the recess 24a at the lowest position. A slight gap 41 is provided between the recess 24a and the flange portion 15a at the lowest position of the lid 15.

One or a plurality of inlets 15b (see FIG. 7) for introducing the nitrogen gas from the nitrogen supply source 33 shown in FIG. 6 into the heating chamber R are formed on the upper peripheral edge of the lid 15. There is. The plurality of inlets 15b are provided at, for example, four places, and communicate with a communication passage 15c formed in a circular shape along the peripheral edge of the lid body 15.
The circular flow path forming member 32 is attached to the heating chamber R so as to communicate with the heating chamber R. Inside the flow path forming member 32,
As shown in the drawing, the stirring plates 44 are arranged alternately up and down along the circumference. The stirring plates 44 may be arranged alternately on the left and right. In addition, a gap between the flow path forming member 32 and the stirring plate 44,
Alternatively, the gaps between the stirring plates 44 may not be uniform on the circumference, and the gaps may be arranged intermittently on the circumference.

The nitrogen gas from the nitrogen supply source 33 is introduced through the valve 34 whose opening is controlled by the controller 37. The flow path forming member is the hot plate 23.
The nitrogen gas from the nitrogen supply source 33 is heated by the heat of the flow path forming member 3 before being introduced into the heating chamber R.
It is heated uniformly while passing through 2, and contributes to the temperature uniformity of the wafer surface during the heat treatment. Further, a device may be provided such that the nitrogen gas is cooled while the nitrogen gas passes through the communication passage 15c and the flow path forming member 32. This can prevent the O ring 45 from being adversely affected by heat.

An exhaust port 13 for exhausting the gas in the heating chamber R is formed in the center of the upper portion of the lid body 15. The exhaust port 1
3 is connected to the exhaust device 36 via a valve 39. The opening of the valve 39 and the control unit 37 is controlled, and the control unit 37 also controls the up-and-down drive of the up-and-down cylinder 54 so that its height position can be adjusted.

Further, as shown in FIG. 7, the flange portion 15
When the lower end of a is lower than the cover 19, the lid 15 and its flange portion 15a and the support 24 are provided.
Also, the gas in the heating chamber R is allowed to flow into the exhaust space S through the flow path A formed between it and the recess 24a. As shown in FIG. 6, the gas accumulated in the exhaust space S is exhausted to an exhaust processing unit (not shown) via the exhaust port 14 and the exhaust passage 35 formed in the casing 18.

Next, referring to the flow shown in FIG.
The processing steps of the SOD system 1 will be described.

First, in the cassette block 10, the unprocessed wafer W is transferred from the wafer cassette CR to the wafer carrier 2.
1 is transferred to the transfer table in the transfer / cooling plate (TCP) belonging to the third set G3 on the processing block 11 side.

The wafer W transferred to the transfer table in the transfer / cooling plate (TCP) is transferred to the cooling processing station (CPL) via the main wafer transfer mechanism 22. Then, in the cooling processing station (CPL), the wafer W is processed by the SOD coating processing station (SCT).
(Step 1).

The wafer W cooled in the cooling processing station (CPL) is transferred to the SO through the main wafer transfer mechanism 22.
It is transported to the D coating processing station (SCT). Then, in the SOD coating processing station (SCT), the wafer W is subjected to SOD coating processing (step 2).

The wafer W subjected to the SOD coating process at the SOD coating processing station (SCT) is transferred to the aging processing station (DAC) via the main wafer transfer mechanism 22. And the aging processing station (DA
In C), the wafer W is subjected to aging treatment by introducing NH3 + H2O into the processing chamber to gel the insulating film material film on the wafer W (step 3).

The wafer W aged in the aging processing station (DAC) is transferred to the main wafer transfer mechanism 22.
To the solvent exchange processing station (DSE). Then, in the solvent exchange processing station (DSE), an exchange chemical is supplied to the wafer W, and the solvent in the insulating film applied on the wafer is replaced with another solvent (step 4).

The wafer W, which has been subjected to the replacement process at the solvent exchange processing station (DSE), is transferred to the low temperature heat processing station (LH) via the main wafer transfer mechanism 22.
P). Then, in the low temperature heat treatment station (LHP), the wafer W is subjected to low temperature heat treatment (step 5).

The wafer W which has been subjected to the low temperature heat treatment at the low temperature heat treatment station (LHP) is transferred to the low oxygen high temperature heat treatment station (OHP) through the main wafer transfer mechanism 22 and subjected to a predetermined heat treatment as described later. Is performed (step 6).

Low oxygen high temperature heat treatment station (OH
The wafer W heat-treated in P) is transferred to the main wafer transfer mechanism 2
Low oxygen cure / cooling treatment station (DC
It is transported to C). Then, in the low oxygen curing / cooling processing station (DCC), the wafer W is subjected to high temperature heating processing in a low oxygen atmosphere and cooling processing (step 7).

Low oxygen curing / cooling processing station (D
The wafer W processed in (CC) is transferred to the cooling plate in the transfer / cooling plate (TCP) via the main wafer transfer mechanism 22. And transfer / cooling plate (TC
On the cooling plate in P), the wafer W is cooled (step 8).

The wafer W cooled by the cooling plate of the transfer / cooling plate (TCP) is transferred to the wafer cassette CR via the wafer transfer body 21 in the cassette block 10.

Next, the operation of the low oxygen high temperature heat treatment station (OHP) in step 6 will be described in detail.

As shown in FIG. 9, with the lid 15 raised, the wafer W is moved from the main wafer transfer mechanism 22 to the lifting pins 5.
Delivered to 8. At this stage, the nitrogen is supplied from the nitrogen supply source 33 (FIG. 6) to the back surface side of the lid body 15 in order to prevent the wafer W from being oxidized while being exhausted by the exhaust device 36. The amount of nitrogen introduced at this time is, for example, 40 liters per minute. Thereafter, as shown in FIG. 10, the lid 15 is lowered so that the lower end of the flange 15a is located at a position lower than the height of the surface of the cover 19 to form the flow path A.

Here, when the lid 15 is lowered,
Conventionally, unlike the present embodiment, the concave portion 24a is not provided and the gas is scattered to the outside introduced on the back surface side of the lid body 15 to generate particles, but in the present embodiment, the gas is flowed. Since the gas is exhausted to the exhaust space S via A, the gas will not leak to the outside of the processing station.
Therefore, it is possible to prevent the generation of particles and prevent adverse effects on other processing stations, the main transport device 22, and the like.

In this embodiment, the flow path A is L-shaped, but if the shape is such that nitrogen gas can be introduced from the heating chamber R into the exhaust space S when the lid 15 is lowered, a straight path or a curved path. Alternatively, the shape may be a combination of both. Further, in order to protect each member, a mechanism such as cooling the flange portion 15a, the support 24 or both is provided so that the nitrogen gas can flow through the channel A.
The temperature may be adjusted when passing through.

After the channel A is formed, this heat treatment is performed for 10 seconds to 30 seconds in the state shown in FIG. At this time, the exhaust from the exhaust port 13 is stopped or reduced by adjusting the valve 39 so that the nitrogen gas is retained in the heating chamber R to prevent the oxidation of the wafer W and the natural exhaust of the gas from the channel A. I do. The amount of nitrogen gas introduced from the nitrogen supply source 33 at this time is, for example, 10 liters per minute.

Next, as shown in FIG.
To form a heating chamber R, the elevating pins 58 are lowered to place the wafer W on the heating plate 23, and for example, 50 seconds to
Heat treatment is performed for 100 seconds. Further, at this time, the exhaust by the exhaust device 36 is started from the state described in FIG. 10, or the exhaust amount is increased to suppress the turbulence of the air flow and the heating chamber R
Exhaust treatment. The amount of nitrogen gas introduced from the nitrogen supply source 33 at this time is, for example, 5 liters per minute.

When the heating process by the heating plate 23 is completed, the elevating pins 58 are raised, the heating process is performed again in the state shown in FIG. 10, and then the lid 15 is further raised. here,
The temperature-controlled nitrogen gas may be supplied to the wafer W by providing a mechanism for cooling the nitrogen gas from the nitrogen supply source 33.

11 and 12 show a plan view and a sectional view of a low oxygen high temperature heat treatment station (OHP) according to another embodiment. In FIGS. 11 and 12, the same components as those in the above-described embodiment are designated by the same reference numerals.

As shown in FIG. 11, a flow straightening plate 46 is provided in the exhaust space S so that the gas exhausted from the processing chamber 51 to the exhaust space S is guided to the exhaust port 14. As a result, the gas from the processing chamber 51 can be efficiently exhausted, and the devices and the like at the four corners S ′ of the space S can be protected from the gas containing various components during the heat treatment.

As shown in FIG. 12, an exhaust plate 48 is attached to the upper portion of the lid 15, and the exhaust plate 48 is provided with a plurality of holes 48a. As a result, the gas in the heating chamber R can be exhausted from the exhaust port 13 through the plurality of holes 48a, so that the flow velocity of the gas at the exhaust port 13 can be reduced as compared with the case where the exhaust plate 48 is not provided. A more stable air flow control can be performed.

The present invention is not limited to the embodiment described above. For example, although the apparatus for processing a semiconductor wafer substrate has been described in the present embodiment, the present invention is not limited to this, and the present invention is also applicable to an apparatus for processing a glass substrate used in a liquid crystal display device or the like.

[0049]

As described above, according to the present invention,
It is possible to prevent generation of particles and prevent adverse effects on other processing devices without leaking gas to the outside of the processing device.

[Brief description of drawings]

FIG. 1 is a plan view showing an overall configuration of an SOD system according to an embodiment of the present invention.

FIG. 2 is a front view of the SOD system shown in FIG.

FIG. 3 is a rear view of the SOD system shown in FIG.

FIG. 4 is a plan view of a low oxygen high temperature heat treatment station (OHP) according to one embodiment.

5 is a cross-sectional view of the low oxygen high temperature heat treatment station (OHP) shown in FIG.

6 is a cross-sectional view of the processing chamber shown in FIG.

FIG. 7 is an enlarged sectional view showing a main part of the present invention.

FIG. 8 is a flowchart showing a series of steps of the SOD system according to the present invention.

FIG. 9 is a cross-sectional view showing the operation of heat treatment according to one embodiment.

FIG. 10 is a diagram showing the same operation.

FIG. 11 is a plan view of a low oxygen high temperature heat treatment station (OHP) according to another embodiment.

12 is a cross-sectional view of the low oxygen high temperature heat treatment station (OHP) shown in FIG.

[Explanation of symbols]

W: Semiconductor wafer S ... Exhaust space R ... Heating room A ... Flow path 13 ... Exhaust port 14 ... Exhaust port 15 ... Lid 15a ... Flange part 15b ... inlet 15c ... communication passage 18 ... Casing 19 ... Cover 23 ... Hot plate 24 ... Support 24a ... Recess 32 ... Flow path forming member 33 ... Nitrogen supply source 34 ... Valve 35 ... Exhaust path 36 ... Exhaust device 37 ... Control unit 39 ... Valve 46 ... Rectifier plate 48 ... Exhaust plate 48a ... hole 54 ... Lifting cylinder

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Koji Sakai 5-3-6 Akasaka, Minato-ku, Tokyo TBS Broadcasting Center Tokyo Electron Stock Company In-house (56) Reference JP 2001-102375 (JP, A) JP 2001-102370 (JP, A) JP 2001-44117 (JP, A) JP 1-209722 (JP, A) JP 9-92595 (JP, A) (58) Fields investigated (Int.Cl) . ⁷ , DB name) H01L 21/31 H01L 21/027 H01L 21/768

Claims (6)

(57) [Claims] 1. A heat plate for heat-treating a substrate, a cover for accommodating the periphery of the heat plate, and a cover provided at an upper end portion at substantially the same height as the surface of the heat plate, and exhausting the inside. A casing having an exhaust port, and a lid body that is arranged so as to be able to move up and down on the hot plate, covers the hot plate in a lowered position, and has a lower end portion that is arranged at a position lower than the height of the cover surface. And a substrate processing apparatus. 2. The substrate processing apparatus according to claim 1, wherein the lid includes a means for introducing an inert gas into a back surface side of the lid, and an exhaust means for exhausting the introduced inert gas. A substrate processing apparatus comprising: 3. The substrate processing apparatus according to claim 2, wherein the inert gas introduced to the back surface side of the lid is further exhausted into the inside of the casing. 4. The substrate processing apparatus according to claim 3, wherein a means for adjusting an ascending / descending position of the lid is adjusted, and a lower end of the lid is adjusted to substantially the same height as the hot plate surface by the adjusting means. The substrate processing apparatus further comprises a control unit for stopping the exhaust operation by the exhaust unit when the substrate is removed. 5. The substrate processing apparatus according to claim 3, further comprising a straightening plate that is arranged around the hot plate and that straightens the inert gas exhausted into the casing and guides it to the exhaust port. A substrate processing apparatus further comprising: 6. Any one of claims 3 to 5
Item 5. The substrate processing apparatus according to item 4, wherein the exhaust unit includes an exhaust plate having a plurality of holes.