JP2016009796A - Substrate heating apparatus, substrate supporting apparatus, substrate processing apparatus and substrate processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate heating apparatus which allows for uniform heating in the substrate plane, regardless of the substrate size, by using microwaves.SOLUTION: A supporting apparatus 5 has a plurality of microwave irradiation units 25 arranged, at a regular interval, in a direction parallel with a mounting surface 21a below a mounting plate 21. Each microwave irradiation unit 25 includes a microwave generator 41 generating microwaves, a microwave radiation port 43 radiating microwaves toward the mounting plate 21, a unit container 45 for supporting the microwave radiation port 43, and a microwave transmission path 47 for transmitting microwaves from the microwave generator 41 to the microwave radiation port 43.

Description

  The present invention relates to a substrate heating apparatus that heats a substrate such as a semiconductor wafer, a substrate support apparatus and a substrate processing apparatus including the substrate heating apparatus, and a substrate processing method.

  In manufacturing a semiconductor device, a substrate such as a semiconductor wafer is heated to a high temperature. For example, in a manufacturing process of a compound semiconductor such as GaN, AlN, and SiC, a process such as epitaxial growth or CVD (chemical vapor deposition) is performed while the substrate is heated to a high temperature of 1000 ° C. or higher, for example, 1100 to 1200 ° C. .

  As a device for heating the substrate, a resistance heating type heater, a lamp type heater, or the like is generally used.

  The resistance heating method has a problem that temperature non-uniformity occurs in the plane of the substrate and a heater pattern is generated in a thin film formed on the substrate. Patent Document 1 proposes a heating device in which a plurality of rectangular heater units are arranged in order to make the heating temperature uniform within the substrate surface. In addition, the resistance heating heater of the type embedded in the substrate support device needs to increase the heat capacity of the substrate support device for uniform heating. There is a problem with sex.

  Lamp heaters are capable of rapid temperature rise and fall and have excellent responsiveness, but have a problem of low power utilization efficiency.

  In addition to the above, an apparatus that utilizes microwave heating is known as an apparatus for heating a substrate. For example, in Patent Document 2, there is provided a heating device that heats a sample stage by irradiating the sample stage with microwaves through a plate-like body in which a plurality of through holes are formed, and heats a substrate placed thereon. Proposed. The heating device disclosed in Patent Document 2 is capable of evenly irradiating a sample stage with microwaves by using a plate-like body having a plurality of through holes as an antenna. However, in the method of Patent Document 2 using a single microwave generation source, it is considered that uniform heat treatment becomes difficult as the substrate size increases.

  Further, in Patent Document 3, a microwave is supplied to a heat generation layer provided in a support device in a direction parallel to the heat generation layer and from a waveguide provided concentrically. A heating apparatus for heating the substrate has been proposed. As described above, in the method of supplying microwaves from concentric waveguides, it is necessary to redesign the transmission path so that the microwave absorption efficiency in the heat generating layer is maximized when the substrate size changes. There is.

Japanese Patent Laid-Open No. 11-354528 JP 2005-268624 A International Publication WO2013 / 145932

  In recent years, the size of the substrate has increased, and it has become increasingly difficult to make the heating temperature uniform within the substrate surface. Therefore, an object of the present invention is to provide a substrate heating apparatus that uses microwaves and enables uniform heat treatment within the substrate surface regardless of the substrate size.

  The substrate heating apparatus of the present invention generates heat when irradiated with microwaves, transmits the heat to the substrate and heats the substrate, and the microwaves independently from the heating member. A plurality of microwave irradiation units. In the substrate heating apparatus of the present invention, the microwave irradiation unit includes a microwave generator that generates the microwave, a microwave radiation port that radiates the microwave toward the heat generating member, and the microwave. And a microwave transmission path for transmitting the microwave between the generator and the microwave radiation port.

  In the substrate heating apparatus of the present invention, the plurality of microwave irradiation units may be arranged in a direction parallel to the lower surface of the heat generating member.

  In the substrate heating apparatus of the present invention, the microwave radiation port may have a microwave radiation window having a polygonal shape in plan view that is microwave transmissive, and the microwave radiation window faces the heat generating member. May be arranged.

  The substrate heating apparatus of the present invention may have a shield portion that prevents leakage of the microwave around the microwave radiation port.

  In the substrate heating apparatus of the present invention, the microwave transmission path includes a waveguide whose one end is connected to the microwave generator, a microwave-permeable pressure bulkhead that closes the other end of the waveguide, And a vacuum waveguide connected to the other end side of the waveguide through a pressure partition. In this case, at least a part of the vacuum waveguide may be filled with a dielectric member.

  In the substrate heating apparatus of the present invention, the vacuum waveguide may be connected to the microwave radiation port on the side opposite to the side connected to the waveguide, and the microwave radiation port may be connected to the vacuum radiation port. You may have the rectangular slot hole which radiates | emits the said microwave in the connection part with a waveguide. In this case, the slot hole may be provided unevenly at a position off the center in the microwave radiation port. Further, the slot hole may be an opening having a stepped portion having a longer side length facing the vacuum waveguide longer than a longer side length facing the microwave radiation window.

  The substrate heating apparatus of the present invention may further include a rotating device that rotates the heat generating member.

  The substrate support apparatus of the present invention includes any one of the above-described substrate heating apparatuses, and places the substrate on the heat generating member.

  A substrate processing apparatus of the present invention includes any one of the above-described substrate heating apparatuses, and performs processing by placing the substrate on the heat generating member.

  The substrate processing method of the present invention uses the substrate processing apparatus to perform processing while heating the substrate.

  The substrate heating apparatus and the substrate support apparatus of the present invention are provided with a plurality of microwave irradiation units that independently irradiate microwaves to the heat generating member, so that uniform heating within the substrate surface is possible regardless of the substrate size. It can be performed. For example, even if the substrate size is increased, uniformity within the substrate surface can be easily ensured by adding a microwave irradiation unit. In addition, the substrate can be heated in a short time by using microwaves. Therefore, the substrate processing apparatus provided with the substrate heating apparatus or the substrate supporting apparatus of the present invention can be controlled with high reliability in various processes that require heating of the substrate, and can be advantageously used.

It is sectional drawing which shows the schematic structure of the substrate processing apparatus which concerns on one embodiment of this invention. It is an expanded sectional view of the microwave irradiation unit in the substrate processing apparatus of FIG. It is a disassembled perspective view of the upper part of the support apparatus in the substrate processing apparatus of FIG. It is a top view which shows arrangement | positioning of the microwave irradiation unit in the substrate processing apparatus of FIG. It is a top view which shows the state which removed the microwave radiation window from the microwave irradiation unit shown in FIG. It is an enlarged plan view of the slot hole formed in the port base. It is sectional drawing in the VII-VII arrow of FIG. It is explanatory drawing which shows the structure of the control part in the substrate processing apparatus of FIG. It is a graph which shows the result of the step-like temperature rising control experiment of the mounting plate using a substrate processing apparatus. It is a graph which shows the result of the rapid temperature rising control experiment of the mounting plate using a substrate processing apparatus. It is a graph which shows another result of the step-like temperature rising control experiment of the mounting plate using a substrate processing apparatus. It is a graph which shows another result of the rapid temperature rising control experiment of the mounting plate using a substrate processing apparatus. It is drawing which shows the simulation result of the zone controllability by a several microwave irradiation unit. It is drawing which shows another simulation result of the zone controllability by a some microwave irradiation unit.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, a substrate processing apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a cross-sectional view showing a schematic configuration of the substrate processing apparatus 1. FIG. 2 is an enlarged cross-sectional view showing a microwave irradiation unit in the substrate processing apparatus 1 of FIG. FIG. 3 is an exploded perspective view of the upper portion of the support device in the substrate processing apparatus 1 of FIG. FIG. 4 is a plan view showing an arrangement of a plurality of microwave irradiation units in the substrate processing apparatus 1 shown in FIG. FIG. 5 is a plan view showing a state where a microwave radiation window is removed from the microwave irradiation unit shown in FIG.

  The substrate processing apparatus 1 performs a film forming process on a semiconductor wafer (hereinafter simply referred to as “wafer”) W for manufacturing a semiconductor device, for example, which is an object to be processed, with a plurality of continuous operations. It is configured to be possible. Here, in the wafer W having a flat shape, the upper surface of the upper and lower surfaces having a large area is a semiconductor device formation surface, and this surface is a main surface to be processed.

  The substrate processing apparatus 1 includes a processing container 3 that accommodates a wafer W, a support device 5 that supports the wafer W in the processing container 3, a gas supply device 7 that supplies gas into the processing container 3, and an inside of the processing container 3. And an exhaust device 9 for evacuating the vacuum.

<Processing container>
The processing container 3 is made of, for example, a metal material such as aluminum, an aluminum alloy, or stainless steel. The processing container 3 is configured to be evacuated, and a processing space S <b> 1 for performing a film forming process on the wafer W is formed.

  The processing container 3 includes a ceiling portion 11 and a bottom wall portion 13, and four side wall portions 15 that connect the ceiling portion 11 and the bottom wall portion 13. The side wall portion 15 is provided with a loading / unloading port 15a. The loading / unloading port 15 a is for loading / unloading the wafer W to / from an external transfer chamber (not shown) adjacent to the processing container 3. A gate valve GV is provided between the processing container 3 and the transfer chamber. The gate valve GV has a function of opening and closing the loading / unloading port 15a. The gate valve GV hermetically seals the processing space S1 of the processing container 3 in the closed state, and between the processing space S1 of the processing container 3 and the transfer chamber in the open state. The wafer W can be transferred.

  The bottom wall portion 13 is formed with a plurality of openings 13a penetrating vertically. Each opening 13a has a rectangular shape in plan view having a long side and a short side, and constitutes a part of the microwave transmission path. Each opening 13a is connected to the waveguide 61 via a vacuum window 63 described later.

<Supporting device>
The supporting device 5 that supports the wafer W includes a disk-shaped mounting plate 21 that supports the wafer W, a rotation support portion 23 that rotatably supports the mounting plate 21, and a lower surface of the mounting plate 21 (wafer W And a plurality of microwave irradiation units 25 that irradiate microwaves independently toward the surface 21b) to be irradiated. In FIG. 1, three microwave irradiation units 25 are illustrated. By having the microwave irradiation unit 25, the support device 5 of the present embodiment also functions as a heating device for heating the wafer W.

(Mounting plate)
The mounting plate 21 is a heat generating member that absorbs microwaves and generates heat. The upper surface of the flat mounting plate 21 is a mounting surface 21a on which the wafer W is mounted, and the lower surface of the mounting plate 21 is an irradiated surface 21b to which microwaves are irradiated. In the substrate processing apparatus 1 of the present embodiment, the size (area) of the mounting surface 21 a is formed slightly larger than the size (area) of the wafer W. Further, the mounting surface 21 a is formed in a circular shape, for example, so as to be substantially the same as the shape of the wafer W. Therefore, heat can be evenly transferred from the entire mounting surface 21a of the mounting plate 21 heated by the microwave irradiation to the entire wafer W mounted thereon by heat conduction or radiation.

  The temperature rise of the object due to dielectric heating by microwave irradiation is proportional to the product of the relative dielectric constant (ε) and the dielectric loss angle (tan δ) of the constituent material. By using a material having a product of 1 or more, more preferably 10 or more, as the material of the mounting plate 21, microwaves are efficiently absorbed and converted into heat, and the mounting plate 21 is heated. be able to. The mounting plate 21 is preferably formed of a material having a heat resistant temperature of 1000 ° C. or higher. From the above, in support device 5 in the present embodiment, microwaves having heat resistance such as SiC, a composite material of SiC and carbon, and a composite material of SiC and carbon nanotube are used as the material of mounting plate 21. It is preferred to use an absorbent material. For example, when the wafer W is heat-treated at a relatively low temperature up to about 600 ° C., a material having a heat resistance of less than 1000 ° C. can be used as the material of the mounting plate 21. Further, from the importance of in-plane temperature uniformity on the wafer W, it is also important that the thermal conductivity is high. Further, since ceramics tend to have larger ε and tan δ at higher temperatures, it is desirable that the product of ε and tan δ is 10 or more at least near the target temperature. Even if this product has a smaller value at low temperatures, etc., it can be used because it gradually generates heat, but there are cases where heating efficiency, microwave leakage, transmission, etc. increase.

(Rotating support)
The rotation support unit 23 rotatably supports the mounting plate 21 on which the wafer W is mounted. The rotation support unit 23 includes a support ring 31 that rotates in the horizontal direction while supporting the mounting plate 21. The support ring 31 is an annular member made of a highly heat-insulating material different from the mounting plate 21, such as quartz or zirconia. As shown in FIG. 3, the inner peripheral side of the upper surface of the support ring 31 is lower than the outer peripheral side, and a step portion 31a is formed. The mounting plate 21 is fitted into and supported by the step portion 31a.

  The rotation support unit 23 includes an internal rotating body 33A that rotates while supporting the support ring 31, and an external rotating body 33B that rotates the internal rotating body 33A in synchronization by rotating itself. The external rotating body 33B is disposed outside the processing container 3. The internal rotating body 33A and the external rotating body 33B include a magnet coupling 35 that transmits a rotational force from the external rotating body 33B to the internal rotating body 33A. The magnet coupling 35 transmits the rotational force of the external rotator 33B to the internal rotator 33A in a non-contact manner across the side wall 15. Therefore, by rotating the external rotating body 33B, the internal rotating body 33A can be rotated, and the support ring 31 and the mounting plate 21 can be rotated in the horizontal direction.

(Microwave irradiation unit)
As shown in FIG. 4, the support device 5 of the present embodiment has seven microwave irradiations arranged at equal intervals in a direction parallel to the mounting surface 21 a and the irradiated surface 21 b below the mounting plate 21. A unit 25 is provided. Each microwave irradiation unit 25 includes a microwave generator 41 that generates microwaves, a microwave radiation port 43 that radiates microwaves toward the mounting plate 21, and a unit container 45 that supports the microwave radiation port 43. And a microwave transmission path 47 for transmitting microwaves from the microwave generator 41 to the microwave radiation port 43.

  In the present embodiment, all the configurations of the seven microwave irradiation units 25 are the same. Hereinafter, for convenience of explanation, the seven microwave irradiation units 25 may be distinguished as reference numerals 25A, 25B, 25C, 25D, 25E, 25F, and 25G. The microwave irradiation unit 25A is disposed at the center, and the microwave irradiation units 25B to 25G are disposed around the microwave irradiation unit 25A. Note that the number of the microwave irradiation units 25 can be arbitrarily increased or decreased according to the size of the wafer W or the like. Moreover, since each microwave irradiation unit 25 can irradiate a microwave independently, it is also possible to heat the mounting plate 21 using only a part of the microwave irradiation units 25.

(Microwave generator)
Although not shown, the microwave generation device 41 includes a microwave generation source such as a magnetron or a klystron, and a power source that applies a high voltage to the microwave generation source. As the microwave generation source, one that can oscillate microwaves of various frequencies can be used. For the microwave generated by the microwave generation source, an optimum frequency can be selected from, for example, an ISM (Industry-Science-Medical) band according to the purpose of processing. For example, the frequency of the microwave is preferably 915 MHz, 2.45 GHz, 5.8 GHz, 24 GHz or the like, and particularly preferably 2.45 GHz.

  Although illustration is omitted, the microwave generator 41 may include a cooling device for cooling the microwave generation source. As the cooling device, for example, an air cooling fan or the like can be used.

(Microwave radiation port)
As shown in FIG. 4, each microwave radiation port 43 has a hexagonal shape in plan view. By making the microwave radiation port 43 hexagonal, when the number of the microwave irradiation units 25 is increased or decreased, by arranging the microwave irradiation units 25 in a honeycomb shape, it becomes easy to make a shape close to a circle as a whole. Each microwave radiation port 43 has a port base 51 connected to a dielectric waveguide 65 described later, and a microwave radiation window 53 fitted in the recess 51 a of the port base 51.

  As shown in FIGS. 3 and 5, the dish-shaped port base 51 has a hexagonal shape in plan view. In the present embodiment, seven port bases 51 are arranged in a honeycomb shape. The port base 51 has a recessed recess 51a and a slot hole 51b that is an opening formed through the bottom of the recess 51a. The port base 51 is made of, for example, a metal such as aluminum, a composite material obtained by coating a ceramic with a high melting point metal material such as tungsten, or a conductive material such as graphite. Among these, when heating the wafer W to a high temperature of 1000 ° C. or higher, it is preferable to use graphite having excellent heat resistance.

  The slot hole 51b of the port base 51 is opened at a position connected to the upper end of a dielectric waveguide 65, which will be described later, and radiates microwaves that have propagated through the dielectric waveguide 65. The slot hole 51b has a rectangular shape having a long side and a short side.

  6 is an enlarged plan view of a slot hole 51b formed in the bottom of the recess 51a in the port base 51, and FIG. 7 is a cross-sectional view taken along the arrow VII-VII. Here, when the length of the short side in the slot hole 51b is L1, and the length of the long side is L2, the ratio (L2 / L1) of the short side length L1 to the long side length L2 in the slot hole 51b is In order to increase the microwave radiation efficiency, for example, it is preferably in the range of 2 to 4.

  Further, as shown in FIGS. 6 and 7, the slot hole 51b, which is an opening penetrating the port base 51, has an upper opening 51b1 and a lower opening 51b2. The upper opening 51b1 and the lower opening 51b2 are formed by providing a step in the opening of the port base 51. The lengths of the short sides of the upper opening 51b1 and the lower opening 51b2 are both L1, but the lengths of the long sides are different. That is, the length of the long side of the upper opening 51b1 is L2, the length of the long side of the lower opening 51b2 is L3, and L2 <L3. In this way, by providing a step in the opening of the slot hole 51b and changing the upper and lower slot lengths, the phase of the reflected wave generated in the slot hole 51b is changed so as to cancel out the traveling wave. The radiation efficiency from the wave radiation port 43 can be increased. The long side length L2 of the slot hole 51b is the length of the long side of the upper opening 51b1.

  The slot hole 51b in the recess 51a of the port base 51 is arbitrarily arranged as long as it is connected to the upper end of the dielectric waveguide 65. From the viewpoint of efficiently and efficiently radiating microwaves from the entire microwave radiation window 53, it is preferable that the slot holes 51b are provided unevenly at positions deviating from the central portion of the bottom of the recess 51a. For example, it is preferable that the center of the slot hole 51b is disposed at a position deviated from the center of the hexagonal recess 51a in plan view by about 1/5 to 2/5 of its inner diameter. By disposing the slot hole 51b close to one side of the bottom of the recess 51a, the electromagnetic field of the microwave radiated from the slot hole 51b is uniformly spread over the entire port base 51 as compared with the case where the slot hole 51b is disposed at the center portion. Can do. Further, the slot hole 51b can be formed at an arbitrary angle in the hexagonal recess 51a in plan view.

  The microwave radiation window 53 transmits the microwave radiated from the slot hole 51 b and radiates it toward the mounting plate 21. The microwave radiation window 53 has a hexagonal column shape in accordance with the shape of the recess 51 a of the port base 51. The microwave radiation window 53 is made of a microwave transmissive material. Examples of the microwave transparent material include quartz, ceramics such as alumina, and dielectrics such as synthetic resin. Among these dielectrics, it is most preferable to use quartz that has heat resistance and easily transmits microwaves.

  The distance (gap) from the upper surface (radiation surface 53a) of the microwave radiation window 53 to the irradiated surface 21b of the opposing mounting plate 21 is within a range of, for example, 1 to 3 mm when the mounting plate 21 is rotated. It is preferable that When the distance from the radiation surface 53a of the microwave radiation window 53 to the irradiated surface 21b of the mounting plate 21 is larger than 3 mm, leakage or reflected waves of the microwave radiated from the microwave radiation window 53 are generated, and the mounting is performed. The absorption efficiency by the mounting plate 21 may decrease. The same applies to the case where the mounting plate 21 is used without being rotated.

  In addition, the distance between the upper surface of the bottom wall of the recess 51a of the port base 51 having the slot hole 51b and the lower surface of the microwave radiation window 53 is preferably 2 mm or less, and more preferably, both are in contact with each other. . If the distance between the recess 51a and the lower surface of the microwave radiation window 53 is larger than 2 mm, a reflected wave due to the microwave radiated from the slot hole 51b is generated, and the absorption efficiency by the mounting plate 21 may be reduced.

(Unit container)
The unit container 45 is supported by fitting the port base 51 into the upper end thereof. The unit container 45 is fixed to the bottom wall portion 13 of the processing container 3, for example. The unit containers 45 have a hexagonal cylindrical shape according to the shape of the port base 51 and are arranged in a honeycomb shape. The unit container 45 has a support shelf 55 that supports the port base 51 therein. The unit container 45 is made of, for example, a metal such as aluminum, a composite material obtained by coating a ceramic with a high melting point metal material such as tungsten, or a conductive material such as graphite. Among these, when heating the wafer W to a high temperature of 1000 ° C. or higher, it is preferable to use graphite having excellent heat resistance.

  The unit container 45 has a choke groove 57 as a shield part for preventing leakage of microwaves. The choke groove 57 is formed so as to surround the periphery thereof in a state in which the microwave radiation port 43 (the port base 51 and the microwave radiation window 53) is fitted. Therefore, in the present embodiment, the choke groove 57 is a hexagonal groove. The depth of the choke groove 57 is preferably λ / 4, for example, with respect to the wavelength λ of the microwave radiated from the microwave radiation port 43. For example, when the frequency of the microwave generated by the microwave generator 41 is 2.45 GHz (λ = about 122 mm), the depth of the choke groove 57 is preferably about 30 mm. Note that the width of the choke groove 57 is related to the size of the gap (the distance from the radiation surface 53a of the microwave radiation window 53 to the irradiated surface 21b of the mounting plate 21), the strength of the electric field, and the like, and therefore the electromagnetic field simulation. It is preferable to determine based on the results of In this way, the choke groove 57 is provided so as to surround each microwave radiation port 43, and microwave leakage between adjacent microwave radiation ports 43 is prevented, thereby improving the microwave irradiation efficiency. Can do.

(Microwave transmission line)
As shown in FIGS. 1 and 2, the microwave transmission path 47 includes a waveguide 61 connected to the microwave generator 41, a vacuum window 63 that closes the upper end of the waveguide 61, and the bottom wall portion 13. The opening 13a is formed, and the dielectric waveguide 65 is connected to the opening 13a and transmits a microwave. Here, the opening 13a and the dielectric waveguide 65 form a vacuum waveguide. Thus, in the present embodiment, the opening 13a is used as a part of the microwave transmission path 47 (that is, a part of the microwave irradiation unit 25). Instead of using the opening 13a as a part of the microwave transmission path 47, a microwave transmission path may be configured by inserting, for example, a waveguide into the opening 13a.

  The waveguide 61 has a rectangular rectangular cross section and a hollow rectangular tube shape, and is disposed below the bottom wall portion 13 of the processing vessel 3. The upper end portion of the waveguide 61 is connected to the opening 13a through the vacuum window 63 so that microwaves can be transmitted. The other end side of the waveguide 61 is connected to the microwave generator 41. The microwave generated in the microwave generator 41 is introduced into the processing container 3 through the waveguide 61 and the vacuum window 63.

  The vacuum window 63 is a pressure partition wall that is interposed between the waveguide 61 and the opening 13a and separates the inside of the waveguide 61 that is at atmospheric pressure from the inside of the opening 13a that is decompressed to a vacuum. The vacuum window 63 can be formed of a microwave transparent material, for example, a dielectric material such as quartz, ceramics such as alumina, and synthetic resin. Among these dielectric materials, it is most preferable to use quartz that has sufficient strength to withstand the pressure difference between atmospheric pressure and vacuum, and easily transmits microwaves.

  The dielectric waveguide 65 connects the opening 13 a and the microwave radiation port 43. The dielectric waveguide 65 is a waveguide in which a dielectric column 65b is filled in a rectangular tube 65a having a rectangular cross section. The rectangular tube 65a is made of, for example, a metal such as aluminum, a composite material obtained by coating a ceramic with a high melting point material such as tungsten, or a conductive material such as graphite. Among these, when heating the wafer W to a high temperature of 1000 ° C. or higher, it is preferable to use graphite having excellent heat resistance.

  The dielectric pillar 65b has a quadrangular prism shape and is inserted into the square cylinder 65a without a gap. The dielectric pillar 65b can be formed of a dielectric material such as quartz, ceramics such as alumina, and synthetic resin. Among these dielectric materials, it is most preferable to use quartz which has heat resistance and easily transmits microwaves. By propagating the microwave using the dielectric pillar 65b having a dielectric constant higher than that of the vacuum as a medium, the wavelength of the waveguide (the inner diameter of the rectangular tube 65a) is shortened compared with the case of propagating in the vacuum. ) Can be reduced. As a result, since the size of one microwave irradiation unit 25 can be reduced, a large number of microwave irradiation units 25 can be arranged in a limited space.

  In the microwave irradiation unit 25 of the present embodiment, the transmission loss due to reflection is minimized as much as possible by optimizing the combination of dimensions, shapes, materials, and the like of each component from the microwave generator 41 to the microwave radiation port 43. Reduced. Specifically, for example, the waveguide 61 in the microwave transmission path 47, the vacuum window 63, the dielectric waveguide 65, the port base 51 (recess 51 a and the slot hole 51 b) in the microwave radiation port 43, and the microwave radiation window 53. The output impedance of the microwave supply source and the input impedance of the load are equal to each other (for example, 50Ω) by selecting the dimensions, shape, material, etc. of the choke groove 57 in the unit container 45. Therefore, in the microwave irradiation unit 25 of the present embodiment, impedance matching using, for example, a tuner is unnecessary, and the matching unit can be omitted and the equipment can be simplified. Moreover, the absorption efficiency of the microwave mounting plate 21 irradiated from each microwave irradiation unit 25 is approximately 90% or more, and has excellent power utilization efficiency. Furthermore, since the microwave transmission efficiency is stable, the temperature control of the mounting plate 21 and the wafer W can be performed with high accuracy and highly reliable heat treatment.

  Although not shown, the support device 5 further includes lift pins that are used when the wafer W is placed on the placement plate 21 and when the wafer W is transferred to or from a transfer device (not shown). May be.

<Gas introduction mechanism>
The substrate processing apparatus 1 further includes a gas supply device 7 that supplies a gas into the processing container 3. The gas supply device 7 is connected to the gas supply source 71 for supplying one or a plurality of different gases, and one to a plurality of pipes 73 (only one) for introducing the gas into the processing vessel 3. As shown). The pipe 73 is connected from the gas supply source 71 to the ceiling portion 11 of the processing container 3.

  The ceiling part 11 is provided with a shower head 75 as a gas introduction part for introducing gas into the processing container 1. The shower head 75 is provided above the support device 5 so as to face the processing space S1. The lower surface of the shower head 75 is parallel to and opposed to the upper surface of the support device 5 (the mounting surface 21a of the mounting plate 21). A plurality of gas injection holes 75 a are formed on the lower surface of the shower head 75. Further, in the shower head 75, a gas diffusion space 75b that communicates with the pipe 73 and diffuses gas is provided. The pipe 73 has one end connected to the gas supply source 71 and the other end connected to the shower head 75.

  The gas supply device 7 and the shower head 75 constitute a gas supply mechanism. The gas supply device 7 selects an appropriate gas type according to the purpose of substrate processing, such as various film forming gases and inert gases, and supplies the gas into the processing container 3 through the pipe 73 and the shower head 75. To do. That is, the gas introduced from the gas supply source 71 into the gas diffusion space 75b in the shower head 75 through the pipe 73 is injected into the processing space S1 below the shower head 75 through the plurality of gas injection holes 75a. Is done. Although not shown, the substrate processing apparatus 1 further includes a mass flow controller and an opening / closing valve provided in the middle of the pipe 73. The types of gases supplied into the processing container 3 and the flow rates of these gases are controlled by a mass flow controller and an opening / closing valve.

  Instead of the gas supply device 7, an external gas supply device that is not included in the configuration of the substrate processing apparatus 1 may be used. Further, the gas introduction part for introducing the gas may be provided at a position other than the ceiling part 11, for example, at the side wall part 15.

<Exhaust mechanism>
The exhaust device 9 has, for example, a vacuum pump (not shown) such as a dry pump or a turbo molecular pump. The substrate processing apparatus 1 further includes an exhaust pipe 81 connecting the exhaust port 13 b formed in the bottom wall portion 13 and the exhaust apparatus 9, and a pressure adjusting valve 83 provided in the middle of the exhaust pipe 81. . The exhaust device 9 is connected to the inside of the processing container 3 through the exhaust pipe 81 and the exhaust port 13b. Accordingly, by operating the vacuum pump of the exhaust device 9, the processing space S1 is evacuated to a predetermined pressure.

<Temperature measurement unit>
The substrate processing apparatus 1 further includes a plurality of radiation thermometers (not shown) that measure the surface temperature of the wafer W, and a temperature measurement unit 85 connected to the plurality of radiation thermometers. The temperature measurement unit 85 can monitor the temperature of a plurality of parts of the wafer W in real time.

<Control unit>
The substrate processing apparatus 1 further includes a control unit 90. Each component of the substrate processing apparatus 1 is connected to the control unit 90 and controlled by the control unit 90. The control unit 90 is typically a computer. FIG. 8 is an explanatory diagram showing the configuration of the control unit 90 shown in FIG. In the example illustrated in FIG. 8, the control unit 90 includes a process controller 91 including a CPU, and a user interface 92 and a storage unit 93 connected to the process controller 91.

  In the substrate processing apparatus 1, the process controller 91 includes each component (for example, microwave generation) related to process conditions such as the heating temperature of the wafer W, the gas flow rate, the pressure in the processing container 3, and the rotation speed of the wafer W. The control means controls the apparatus 41, the gas supply apparatus 7, the exhaust apparatus 9, the rotation support unit 23, and the like.

  The user interface 92 includes a keyboard and touch panel on which a process manager manages command processing for managing the substrate processing apparatus 1, a display for visualizing and displaying the operating status of the substrate processing apparatus 1, and the like.

  The storage unit 93 stores a control program (software) for realizing various processes executed by the substrate processing apparatus 1 under the control of the process controller 91, a recipe in which processing condition data and the like are recorded. . The process controller 91 calls and executes an arbitrary control program or recipe from the storage unit 93 as necessary, such as an instruction from the user interface 92. Thereby, a desired process is performed in the processing container 3 of the substrate processing apparatus 1 under the control of the process controller 91. In addition, the process controller 91 refers to real-time temperature data of one or a plurality of parts of the wafer W measured by the temperature measuring unit 85 and feeds back to each microwave irradiation unit 25, thereby allowing the microwave generator 41 to Control of microwave output, ON / OFF time, etc. can be performed.

  As the control program and the recipe, for example, a program stored in a computer-readable storage medium such as a CD-ROM, a hard disk, a flexible disk, a flash memory, or a DVD can be used. Also, the above recipe can be transmitted from other devices as needed via, for example, a dedicated line and used online.

  In the substrate processing apparatus 1 having the above configuration, the wafer W can be subjected to heat treatment by the support device 5 or treatment such as film formation while being heated by the support device 5.

[Processing procedure]
Next, in the substrate processing apparatus 1, a procedure for performing the film forming process on the wafer W while heating will be described. First, for example, a command is input from the user interface 92 to the process controller 91 so as to perform a film forming process in the substrate processing apparatus 1. Next, the process controller 91 receives this command and reads a recipe stored in the storage unit 93 or a computer-readable storage medium. Next, each end device of the substrate processing apparatus 1 (for example, the microwave generation apparatus 41, the gas supply apparatus 7, the exhaust apparatus 9, and the rotation support is performed so that the film forming process is executed according to the conditions based on the recipe. The control signal is sent to the unit 23).

  Next, the gate valve GV is opened, and the wafer W is loaded into the processing container 3 via the loading / unloading port 15a by a transfer device (not shown). Then, the wafer W is transferred to the mounting plate 21 of the support device 5. Next, the gate valve GV is closed, and the processing space S1 in the processing container 3 is evacuated by the exhaust device 9 under reduced pressure. Further, by rotating the support ring 31 of the rotation support portion 23 of the support device 5 in the horizontal direction, the wafer W placed thereon is rotated together with the placement plate 21.

  Next, in the microwave irradiation unit 25, a voltage is applied to, for example, a magnetron of the microwave generator 41 to generate a microwave. The microwave generated in the microwave generator 41 propagates through the waveguide 61 and is transmitted to the microwave radiation port 43 through the vacuum window 63, the opening 13 a of the bottom wall 13, and the dielectric waveguide 65. . In each microwave radiation port 43, microwaves are evenly emitted from the entire microwave radiation window 53 toward the mounting plate 21 through the slot holes 51 b of the port base 51. The microwave irradiated to the mounting plate 21 is absorbed by the mounting plate 21 made of a dielectric, and the mounting plate 21 is heated to a high temperature of, for example, 1000 ° C. or higher. The heat of the mounting plate 21 is transmitted to the wafer W mounted on the mounting surface 21a by heat conduction, radiation, etc., and the wafer W is heated to a desired temperature. The temperature of the plurality of parts of the wafer W is measured by the temperature measuring unit 85.

  When the temperature of the wafer W has risen to a predetermined temperature, the gas supply device 7 introduces a raw material gas having a predetermined flow rate from the shower head 75 into the processing space S <b> 1 in the processing container 3. The processing space S1 is adjusted to a predetermined pressure, for example, in the range of 10 to 1000 Pa by adjusting the exhaust amount and the gas supply amount. Then, a thin film of a compound semiconductor such as GaN, AlN, or SiC can be formed on the main surface of the wafer W heated to a predetermined temperature, for example, by epitaxial growth.

  When a control signal for terminating the film forming process is sent from the process controller 91 to each end device of the substrate processing apparatus 1, the microwave generation by the microwave generator 41 is stopped, the supply of the source gas is stopped, and further The rotation of the support ring 31 is stopped, and the processing for the wafer W is completed. Next, after adjusting the pressure of the processing space S1, the gate valve GV is opened. Then, the wafer W is lifted to a delivery position using lift pins (not shown), and then the wafer W is delivered to an external transfer device and unloaded from the processing container 3.

  The substrate processing apparatus 1 according to the present embodiment includes seven microwave irradiation units 25 that can independently generate and radiate microwaves. Therefore, each microwave irradiation unit 25 irradiates the mounting plate 21. Microwave output can be individually controlled. For example, the microwave output can be changed or the microwave ON / OFF time can be changed between the central microwave irradiation unit 25A and the surrounding microwave irradiation units 25B to 25G. Thus, the temperature distribution in the surface of the mounting plate 21 is reduced, the temperature distribution between the central portion and the peripheral portion of the wafer W is prevented, and uniform heat transfer to the wafer W is enabled.

  Further, with respect to an arbitrary microwave irradiation unit 25 among the microwave irradiation units 25A to 25G, the central portion of the wafer W can be changed by changing the microwave output or changing the microwave ON / OFF time. It is possible to perform temperature control not only in the peripheral portion but also in a more fragmented region.

  The substrate processing apparatus 1 is not limited to a film forming process such as epitaxial growth or CVD (chemical vapor deposition) as long as it is a process that involves heating the wafer W in a semiconductor device manufacturing process. It can be applied to various uses such as processing, plasma film forming processing, and plasma modification processing.

  Next, experimental results confirming the effects of the present invention will be described with reference to FIGS. The wafer W was heated using a substrate processing apparatus having the same configuration as the substrate processing apparatus 1 of FIG. The number of installed microwave irradiation units 25 was seven.

  In the microwave generator 41 of each microwave irradiation unit 25, by generating a microwave with an output of 800 W and irradiating the mounting plate 21, the set temperature is changed in steps approximately every 3 minutes, The mounting plate 21 was heated stepwise. During the temperature increase to each set temperature set in a step shape, the microwave was turned on, and the microwave ON / OFF was appropriately controlled before and after each set temperature. The temperature rise data of the mounting plate 21 at that time is shown in FIG. From FIG. 9, the mounting plate 21 could be heated stepwise to about 600 ° C. over about 1700 seconds. Further, in the temperature raising process, the temperature could be raised stepwise (step-like) with good controllability approximately every 50 ° C.

  FIG. 10 shows the surface temperature (vertical axis left) and the microwave output (vertical axis right) of the mounting plate 21 when the microwave output from each microwave irradiation unit 25 is set to 800 W and the temperature is rapidly increased. Show. From FIG. 10, the mounting plate 21 reached 500 ° C. in a short time of about 170 seconds and then stabilized.

  In addition, the microwave generator 41 of each microwave irradiation unit 25 generates microwaves with an output of about 1300 W and irradiates the mounting plate 21, thereby changing the set temperature almost every six minutes. The mounting plate 21 was heated step by step. During the temperature increase to each set temperature set in a step shape, the microwave was turned on, and the microwave ON / OFF was appropriately controlled before and after each set temperature. The temperature rise data of the mounting plate 21 at that time is shown in FIG. From FIG. 11, the mounting plate 21 could be heated stepwise to about 700 ° C. over about 3000 seconds. Further, in the temperature raising process, the temperature could be raised stepwise (step-like) with good controllability approximately every 50 ° C.

  FIG. 12 shows the surface temperature (vertical axis left) of the mounting plate 21 when the microwave output from each microwave irradiation unit 25 is set to about 1300 W and the temperature is rapidly increased. From FIG. 12, the mounting plate 21 reached 700 ° C. in a short time of about 250 seconds, and then almost stabilized.

  Next, a simulation result of zone controllability when a plurality of microwave irradiation units 25 are used will be described with reference to FIGS. 13 and 14. FIG. 13 and FIG. 14 show electromagnetic field simulation results when 19 microwave irradiation units 25 are arranged in a honeycomb shape by zoning into three regions of 1 center, 6 in the middle, and 12 in the outer periphery. . FIG. 13 shows a case where microwaves are irradiated from only the middle six microwave irradiation units 25. FIG. 14 shows a case in which the microwave power ratio is changed from the center 1, the middle 6 and the outer periphery 12 microwave irradiation units 25 at a ratio of center: intermediate: outer periphery = 1: 2: 3. Show. Although FIG. 13 and FIG. 14 are difficult to discriminate because of black and white display, a common tendency can be seen for each of the central, intermediate, and outer peripheral zones. Accordingly, from FIG. 13 and FIG. 14, the microwave irradiation units 25 function independently by dividing the plurality of microwave irradiation units 25 into three zones and individually changing the power for each zone. It was shown that the current density can be controlled for every three zones.

  According to the substrate processing apparatus 1 of the present embodiment, a plurality of microwave irradiation units 25 that irradiate microwaves independently to the mounting plate 21 that is a heat generating member are provided, so that the size of the wafer W can be reduced. Regardless, uniform heating can be performed in the plane of the wafer W. For example, even if the size of the wafer W increases, it is possible to easily ensure uniformity in the plane of the wafer W by increasing the number of the microwave irradiation units 25. Further, the temperature of the wafer W can be raised in a short time by using the microwave. Therefore, the substrate processing apparatus 1 can perform temperature control with high reliability in various processes that require heating of the wafer W, and can be advantageously used.

  In the substrate processing apparatus 1, by removing the mounting plate 21 or introducing a microwave into the processing container 3 in a state where a member made of a microwave transmissive material is attached instead of the mounting plate 21, The inside of the processing container 3 can be cleaned. In this case, while introducing the cleaning gas from the gas supply device 7 through the shower head 75, microwaves are introduced into the processing container 3 from the plurality of microwave irradiation units 25, and cleaning gas plasma is generated in the processing container 3. What is necessary is just to generate.

  In addition, this invention is not limited to the said embodiment, A various change is possible. For example, the substrate processing apparatus of the present invention is not limited to a case where a semiconductor wafer is used as a substrate, but can be applied to a substrate processing apparatus using, for example, a solar cell panel substrate or a flat panel display substrate as a substrate.

  Further, the number of microwave irradiation units 25 installed in the substrate processing apparatus 1 is not limited to seven, and may be, for example, 2 to 6, or 8 or more, depending on the size of the substrate. As an example, when processing a wafer W having a diameter of 300 mm, about 19 small microwave irradiation units 25 each having a magnetron with an output of about 1 kW may be arranged. Also. The arrangement of the microwave irradiation unit 25 is also arbitrary.

  The shape of the microwave radiation port 43 is not limited to a hexagon in plan view, and may be a polygon such as a triangle or a quadrangle, a circle, an ellipse, or the like.

  DESCRIPTION OF SYMBOLS 1 ... Substrate processing apparatus, 3 ... Processing container, 5 ... Support apparatus, 7 ... Gas supply apparatus, 9 ... Exhaust apparatus, 10 ... Microwave introduction port, 11 ... Ceiling part, 13 ... Bottom wall part, 13a ... Opening, 13b DESCRIPTION OF SYMBOLS ... Exhaust port, 15 ... Side wall part, 15a ... Loading / unloading port, 21 ... Mounting plate, 21a ... Mounting surface, 21b ... Irradiated surface, 23 ... Rotation support part, 25 ... Microwave irradiation unit, 31 ... Support ring, 31a: Stepped portion, 33A: Internal rotating body, 33B: External rotating body, 35 ... Magnet coupling, 41 ... Microwave generator, 43 ... Microwave radiation port, 45 ... Unit container, 47 ... Microwave transmission path, 51 ... Port base, 53 ... Microwave radiation window, 51a ... Recess, 51b ... Slot hole, 57 ... Choke groove, 61 ... Waveguide, 63 ... Vacuum window, 65 ... Dielectric waveguide, 65a ... Square tube, 71 ... Gas supply source 73 ... Pipe, 75 ... Shower head, 75a ... Gas injection hole, 75b ... Gas diffusion space, 81 ... Exhaust pipe, 83 ... Pressure adjustment valve, 85 ... Temperature measuring unit, 90 ... Control unit, GV ... Gate valve, W ... Semiconductor wafer, S1 ... processing space

Claims (13)

A flat plate-like heat generating member that generates heat by being irradiated with microwaves and transfers the heat to the substrate to heat the substrate;
A plurality of microwave irradiation units that irradiate the microwaves independently to the heating member;
With
The microwave irradiation unit is:
A microwave generator for generating the microwave;
A microwave radiation port for radiating the microwave toward the heat generating member;
A microwave transmission path for transmitting the microwave between the microwave generator and the microwave radiation port;
A substrate heating apparatus.   The substrate heating apparatus according to claim 1, wherein the plurality of microwave irradiation units are arranged in a direction parallel to a lower surface of the heat generating member.   The microwave radiation port has a microwave radiation window having a polygonal shape in plan view that is microwave transmissive, and the microwave radiation window is disposed to face the heat generating member. 3. The substrate heating apparatus according to 2.   The substrate heating apparatus according to claim 3, further comprising a shield portion that prevents leakage of the microwave around the microwave radiation port. The microwave transmission path is a waveguide having one end connected to the microwave generator;
A microwave permeable pressure bulkhead closing the other end of the waveguide;
A vacuum waveguide connected to the other end of the waveguide via the pressure partition;
The substrate heating apparatus according to claim 3 or 4, further comprising:   6. The substrate heating apparatus according to claim 5, wherein at least a part of the vacuum waveguide is filled with a dielectric member.   The vacuum waveguide is connected to the microwave radiating port on the side opposite to the side connected to the waveguide, and the microwave radiating port is connected to the micro wave radiating port at the connection portion with the vacuum waveguide. The substrate heating apparatus according to claim 5, further comprising a rectangular slot hole that radiates a wave.   The substrate heating apparatus according to claim 7, wherein the slot hole is unevenly provided at a position off the center in the microwave radiation port.   8. The substrate according to claim 7, wherein the slot hole is an opening having a step portion having a longer side length facing the vacuum waveguide longer than a length of the longer side facing the microwave radiation window. Heating device.   The substrate heating apparatus according to claim 1, further comprising a rotating device that rotates the heat generating member.   A substrate support apparatus comprising the substrate heating apparatus according to claim 1, wherein the substrate is placed on the heat generating member.   A substrate processing apparatus comprising the substrate heating apparatus according to claim 1, wherein the substrate is placed on the heat generating member to perform processing.   A substrate processing method using the substrate processing apparatus according to claim 12 to perform processing while heating the substrate.