Substrate processing apparatus and control method

Abstract

This technology provides an improvement in the uniformity of processing applied to substrates. [Solution] A substrate processing apparatus according to one aspect of the present disclosure comprises a processing container, a mounting table for supporting a substrate within the processing container, an upper member provided opposite to the mounting table and forming a processing space between itself and the mounting table, a gap control unit for controlling the gap between the mounting table and the upper member, and a flow straightening member provided around the processing space, wherein the flow straightening member has an opening that allows at least a portion of the gas flowing out of the processing space to pass through.

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus and a control method.

Background Art

[0002] Techniques for controlling the conductance of the space between a processing space and an exhaust port have been disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technique capable of improving the uniformity of processing on a substrate.

Means for Solving the Problems

[0005] A substrate processing apparatus according to an aspect of the present disclosure includes a processing container, a mounting table that supports a substrate in the processing container, an upper member provided to face the mounting table and forming a processing space between the upper member and the mounting table, a gap control unit that controls the interval of a gap between the mounting table and the upper member, and a rectifying member provided around the processing space, wherein the rectifying member has an opening that allows at least a part of the gas flowing out from the processing space to flow through.

Effects of the Invention

[0006] According to the present disclosure, the uniformity of processing on a substrate can be improved.

Brief Description of the Drawings

[0007] [Figure 1] This is a cross-sectional view showing a substrate processing apparatus according to an embodiment. [Figure 2] This is a perspective view showing an example of a flow rectifier. [Figure 3] Figure (1) illustrates the control method for a substrate processing apparatus according to an embodiment. [Figure 4] Figure (2) illustrates the control method for the substrate processing apparatus according to the embodiment. [Figure 5] Figure (3) illustrates the control method for the substrate processing apparatus according to the embodiment. [Figure 6] Figure (4) illustrates the control method for the substrate processing apparatus according to the embodiment. [Modes for carrying out the invention]

[0008] Hereinafter, exemplary embodiments of the present disclosure, not limited to those described herein, will be described with reference to the attached drawings. In all attached drawings, identical or corresponding members or components are denoted by the same or corresponding reference numerals, and redundant descriptions are omitted.

[0009] (Substrate processing equipment) The substrate processing apparatus 100 according to the embodiment will be described with reference to Figures 1 and 2. Figure 1 is a cross-sectional view showing the substrate processing apparatus 100 according to the embodiment. Figure 2 is a perspective view showing an example of a rectifier member 22.

[0010] The substrate processing apparatus 100 includes a processing container 1, a mounting table 2, a shower head 3, an exhaust unit 4, a gas supply unit 5, an RF power supply unit 8, and a control circuit 9.

[0011] The processing container 1 has a substantially cylindrical shape. The processing container 1 is made of a metal such as aluminum. The processing container 1 houses a substrate W. The substrate W is, for example, a semiconductor wafer. An inlet / outlet 11 for loading or unloading the substrate W is formed in the side wall of the processing container 1. The inlet / outlet 11 is opened and closed by a gate valve 12. An annular exhaust duct 13 with a rectangular cross-section is provided on the main body of the processing container 1. An exhaust port 13p is formed in the outer wall of the exhaust duct 13. There is, for example, one exhaust port 13p. A top wall 14 is provided on the upper surface of the exhaust duct 13 so as to close the upper opening of the processing container 1 via an insulating member 16. The space between the exhaust duct 13 and the insulating member 16 is airtightly sealed with a sealing member 15. The sealing member 15 may be, for example, an O-ring.

[0012] The mounting table 2 horizontally supports the substrate W within the processing container 1. The mounting table 2 has a disc shape. The outer diameter of the mounting table 2 is larger than, for example, the outer diameter of the substrate W. The mounting table 2 is made of a ceramic material such as AlN, or a metallic material such as aluminum or nickel alloy. A heater 21 is provided inside the mounting table 2. The heater 21 is powered by a heater power supply (not shown) and generates heat. By generating heat, the heater 21 heats the substrate W. A thermocouple (not shown) is provided near the upper surface of the mounting table 2. By controlling the output of the heater 21 using the temperature signal of the thermocouple, the substrate W is controlled to a predetermined temperature.

[0013] A support member 23 is provided on the bottom surface of the mounting base 2. The support member 23 supports the mounting base 2. The support member 23 extends from the center of the bottom surface of the mounting base 2, through a hole formed in the bottom wall of the processing container 1, and downwards to the processing container 1. The lower end of the support member 23 is connected to a lifting mechanism 24. The lifting mechanism 24 controls the gap between the mounting base 2 and the shower plate 32 by raising and lowering the mounting base 2 via the support member 23. The lifting mechanism 24 is an example of a gap control unit. A flange portion 25 is attached to the lower part of the support member 23 below the processing container 1. A bellows 26 is provided between the bottom surface of the processing container 1 and the flange portion 25. The bellows 26 partitions the atmosphere inside the processing container 1 from the outside air and expands and contracts in accordance with the raising and lowering movement of the mounting base 2.

[0014] Three support pins (only two are shown) are provided near the bottom surface of the processing container 1, protruding upward from the lifting plate 27a. The support pins 27 are raised and lowered via the lifting plate 27a by a lifting mechanism 28 provided below the processing container 1. The support pins 27 are inserted through holes 2a provided in the mounting base 2 and can protrude and retract relative to the upper surface of the mounting base 2. By raising and lowering the support pins 27, the substrate W is transferred between the transport device (not shown) and the mounting base 2.

[0015] A cover member 29 is fixed to the mounting base 2. The cover member 29 moves up and down together with the mounting base 2. The cover member 29 covers the bottom and sides of the mounting base 2. Together with the exhaust duct 13, the cover member 29 forms a diffusion space Se. The cover member 29 is made of ceramics such as alumina. The diffusion space Se is provided around the processing space 38, which will be described later. The diffusion space Se diffuses the gas flowing out of the processing space 38.

[0016] The shower head 3 supplies gas into the processing container 1 in a shower-like manner. The shower head 3 is installed facing the mounting base 2. The shower head 3 is made of metal. The shower head 3 has approximately the same diameter as the mounting base 2. The shower head 3 has a main body 31 and a shower plate 32. The main body 31 is fixed to the top wall 14 of the processing container 1. The shower plate 32 is connected below the main body 31. The shower plate 32 is an example of an upper member. A gas diffusion space 33 is formed between the main body 31 and the shower plate 32. A gas introduction hole 36 is provided in the gas diffusion space 33 so as to penetrate the top wall 14 and the center of the main body 31. An annular projection 34 protruding downward is provided on the periphery of the shower plate 32. A gas discharge hole 35 is formed in the flat part inside the annular projection 34. When the mounting base 2 is in the processing position, a processing space 38 is formed between the mounting base 2 and the shower plate 32, and an annular gap 39 is formed when the upper surface of the mounting base 2 and the annular projection 34 are in close proximity. The processing space 38 communicates with the diffusion space Se through the annular gap 39. The spacing A1 of the annular gap 39 is controlled by the lifting mechanism 24 raising and lowering the mounting base 2.

[0017] Around the processing space 38, a flow rectifying member 22 is provided. The flow rectifying member 22 has a cylindrical shape. The flow rectifying member 22 is provided so as to cover the side surface of the mounting table 2 and the side surface of the shower plate 32. The flow rectifying member 22 is disposed closer to the annular gap 39 than the exhaust port 13p. In this case, since the volume of the diffusion space Se can be increased, the flow of gas to the exhaust port 13p is hardly obstructed. The flow rectifying member 22 is supported by the cover member 29. The flow rectifying member 22 moves up and down integrally with the cover member 29 and the mounting table 2. The flow rectifying member 22 has slits 22s. The slits 22s are provided along the circumferential direction. The slits 22s may be divided into a plurality (two in the example of FIG. 2) in the circumferential direction. The slits 22s allow at least a part of the gas flowing out from the processing space 38 through the annular gap 39 to flow through and guide it to the diffusion space Se. The height A2 of the slits 22s may be larger than the minimum value of the interval A1 of the annular gap 39 when processing is performed on the substrate W in the processing space 38. The height A2 of the slits 22s may be smaller than the maximum value of the interval A1 of the annular gap 39 when processing is performed on the substrate W in the processing space 38. The slits 22s are an example of an opening.

[0018] The exhaust unit 4 evacuates the inside of the processing container 1. The exhaust unit 4 includes an exhaust pipe 41 and an exhaust mechanism 42. The exhaust pipe 41 is connected to the exhaust port 13p. The exhaust mechanism 42 includes a vacuum pump connected to the exhaust pipe 41 and a pressure control valve. During processing, the gas in the processing space 38 reaches the diffusion space Se through the annular gap 39, and is discharged from the exhaust port 13p through the exhaust pipe 41 by the exhaust mechanism 42.

[0019] The gas supply unit 5 supplies various gases to the shower head 3. The gas supply unit 5 includes a gas source 51 and a gas line 52. The gas source 51 includes a supply source of various gases, a mass flow controller, and a valve. The various gases are introduced from the gas source 51 into the gas diffusion space 33 through the gas line 52 and the gas introduction holes 36. Examples of the various gases include film-forming gases, etching gases, purge gases, and the like.

[0020] The substrate processing apparatus 100 is a capacitively coupled plasma apparatus in which the mounting stage 2 functions as the lower electrode and the shower head 3 functions as the upper electrode. The mounting stage 2 is grounded. The shower head 3 is connected to the RF power supply unit 8.

[0021] The RF power supply unit 8 supplies high-frequency power (hereinafter also referred to as "RF power") to the shower head 3. The RF power supply unit 8 includes an RF power supply 81, a matching unit 82, and a power supply line 83. The RF power supply 81 is a power source that generates RF power. The RF power has a frequency suitable for plasma generation. The frequency of the RF power is, for example, within the range of 450 kHz in the low frequency band to 2.45 GHz in the microwave band. The RF power supply 81 is connected to the main unit 31 via the matching unit 82 and the power supply line 83. The matching unit 82 has a circuit for matching the load impedance to the internal impedance of the RF power supply 81. The RF power supply unit 8 may also be configured to supply RF power to the mounting base 2.

[0022] The control circuit 9 is an electronic circuit such as a CPU (Central Processing Unit), FPGA (Field Programmable Gate Array), or ASIC (Application Specific Integrated Circuit). The control circuit 9 performs the various control operations described in this specification by executing instruction codes stored in memory or by being designed as a circuit for a special application.

[0023] (Control method) Referring to Figures 3 to 6, a control method for the substrate processing apparatus 100 according to the embodiment will be described. Figures 3 to 6 are diagrams illustrating a control method for the substrate processing apparatus 100 according to the embodiment. In Figures 3 to 6, the arrows shown in the figures indicate the flow of gas.

[0024] The control method of the substrate processing apparatus 100 may include the first control in which the lifting mechanism 24 controls the interval A1 of the annular gap 39 so that the interval A1 of the annular gap 39 is the same as or smaller than the height A2 of the slit 22s. The first control may include the lifting mechanism 24 moving the mounting table 2 to the first position.

[0025] The first position is a position where the interval A1 of the annular gap 39 is smaller than the height A2 of the slit 22s (A1 < A2) as shown in FIG. 3, or a position where the interval A1 of the annular gap 39 is the same as the height A2 of the slit 22s (A1 = A2) as shown in FIG. 4. When the mounting table 2 is in the first position, the gas supplied from the shower plate 32 to the processing space 38 passes through the annular gap 39 and then is discharged into the diffusion space Se through the slit 22s. At this time, since the interval A1 of the annular gap 39 is smaller than or the same as the height A2 of the slit 22s, the rectifying member 22 does not obstruct the gas flow. Therefore, the conductance in the space between the processing space 38 and the diffusion space Se is determined by the interval A1 of the annular gap 39, and the portion where the conductance is dominant is the peripheral portion of the mounting table 2. As a result, even if there is one exhaust port 13p, the gas can be evenly discharged from around the processing space 38. The interval A1 of the annular gap 39 when the mounting table 2 is in the first position is, for example, 0.5 mm or more and 1.0 mm or less. In this case, the gas is likely to be evenly discharged from around the processing space 38.

[0026] The control method of the substrate processing apparatus 100 may include the second control in which the lifting mechanism 24 controls the interval A1 of the annular gap 39 so that the interval A1 of the annular gap 39 is larger than the height A2 of the slit 22s and the lower end 34a of the annular protrusion 34 is lower than the upper end 22t of the rectifying member 22. The second control may include the lifting mechanism 24 moving the mounting table 2 to the second position.

[0027] The second position is, as shown in Figure 5, a position where the spacing A1 of the annular gap 39 is greater than the height A2 of the slit 22s (A1 > A2), and the lower end 34a of the annular projection 34 is lower than the upper end 22t of the rectifier member 22. When the mounting base 2 is in the second position, the gas supplied from the shower plate 32 to the processing space 38 passes through the annular gap 39 and then is discharged through the slit 22s to the diffusion space Se. At this time, because the spacing A1 of the annular gap 39 is greater than the height A2 of the slit 22s, the conductance in the space between the processing space 38 and the diffusion space Se is determined by the height A2 of the slit 22s, and the area where conductance is dominant is the periphery of the mounting base 2. As a result, even if there is only one exhaust port 13p, the gas can be discharged evenly from around the processing space 38 without depending on the spacing A1 of the annular gap 39. When the mounting base 2 is in the second position, the spacing A1 of the annular gap 39 is, for example, greater than 1.0 mm and less than 5.0 mm.

[0028] The control method for the substrate processing apparatus 100 may include the lifting mechanism 24 performing a third control to control the spacing A1 of the annular gap 39 such that the lower end 34a of the annular projection 34 is higher than the upper end 22t of the rectifying member 22. The third control may include the lifting mechanism 24 moving the mounting table 2 to a third position.

[0029] The third position is, as shown in Figure 6, a position where the lower end 34a of the annular projection 34 is higher than the upper end 22t of the rectifying member 22. When the mounting base 2 is in the third position, the gas supplied from the shower plate 32 to the processing space 38 passes through the annular gap 39 and then, in addition to the slit 22s, is discharged to the diffusion space Se by passing over the rectifying member 22. Therefore, when a large flow rate of gas is supplied from the shower plate 32 to the processing space 38, the gas can be efficiently discharged from the processing space 38 to the diffusion space Se. The spacing A1 of the annular gap 39 when the mounting base 2 is in the third position is, for example, 5.0 mm or more.

[0030] The lifting mechanism 24 moves the mounting platform 2 to a first or second position when processing is performed on the substrate W in the processing space 38. In this case, gas can be evenly discharged from around the processing space 38 when processing is performed on the substrate W, thereby improving the uniformity of the processing on the substrate W.

[0031] The lifting mechanism 24 moves the mounting platform 2 to a third position, for example, when purging the processing space 38. In this case, a large flow rate of purge gas can be supplied to the processing space 38 to purge it, thus shortening the purging time.

[0032] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The above embodiments may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims.

[0033] In the above embodiment, a case was described in which one exhaust port 13p is provided on the outer wall of the exhaust duct 13, but the disclosure is not limited thereto. For example, two or more exhaust ports 13p may be provided along the circumferential direction of the exhaust duct 13.

[0034] In the embodiments described above, the case in which the opening is a slit 22s has been explained, but the disclosure is not limited thereto. For example, the opening may be a plurality of punch holes provided along the circumferential direction of the rectifying member 22.

[0035] In the above embodiment, the case in which the upper member is a shower plate 32 was described, but the disclosure is not limited thereto. The upper member may be any member that forms a processing space 38 between itself and the mounting base 2.

[0036] In the above embodiment, a case was described in which the spacing A1 of the annular gap 39 is adjusted by raising and lowering the mounting base 2, but the disclosure is not limited thereto. For example, the shower plate 32 may be configured to be able to move up and down, and the spacing A1 of the annular gap 39 may be adjusted by raising and lowering the shower plate 32. For example, the mounting base 2 and the shower plate 32 may be configured to be able to move up and down, and the spacing A1 of the annular gap 39 may be adjusted by raising and lowering both the mounting base 2 and the shower plate 32. [Explanation of Symbols]

[0037] 1. Processing container 2. Mounting platform 22 Rectifying member 22s Slit 24 Lifting mechanism 32 shower plates 38 Processing space 39 Annular gap 100 Substrate Processing Equipment W board

Claims

1. Processing container and A mounting platform for supporting the substrate within the processing container, An upper member provided opposite the aforementioned mounting base, forming a processing space between it and the aforementioned mounting base, A gap control unit that controls the gap between the mounting base and the upper member, A flow straightening member provided around the processing space, Equipped with, The rectifying member has an opening that allows at least a portion of the gas flowing out of the processing space to pass through. Circuit board processing equipment.

2. The gap control unit is A first control that controls the spacing of the gaps so that the spacing of the gaps is the same as or less than the height of the opening, A second control that controls the gap so that the gap is greater than the height of the opening and the lower end of the upper member is lower than the upper end of the rectifying member, A third control that controls the gap spacing such that the lower end of the upper member is higher than the upper end of the rectifying member, Execute The substrate processing apparatus according to claim 1.

3. The gap control unit executes the first control or the second control when processing is performed on the substrate in the processing space. The substrate processing apparatus according to claim 2.

4. The gap control unit executes the third control when purging the processing space. The substrate processing apparatus according to claim 2.

5. The height of the opening is greater than the minimum value of the gap spacing when processing is performed on the substrate in the processing space. The substrate processing apparatus according to claim 1.

6. The height of the opening is smaller than the maximum value of the gap when processing is performed on the substrate in the processing space. The substrate processing apparatus according to claim 1.

7. The gap control unit controls the gap by raising and lowering the aforementioned base. A substrate processing apparatus according to any one of claims 1 to 6.

8. The rectifier member is movable up and down together with the base described above. The substrate processing apparatus according to claim 7.

9. The gap control unit controls the gap by raising and lowering the upper member. A substrate processing apparatus according to any one of claims 1 to 6.

10. The upper member is a shower plate that supplies the gas to the processing space in a shower-like manner. The substrate processing apparatus according to claim 1.

11. The exhaust duct is provided around the processing space and forms a diffusion space for diffusing the gas flowing out of the processing space. The substrate processing apparatus according to claim 1.

12. A control method for a substrate processing apparatus, The substrate processing apparatus is Processing container and A mounting platform for supporting the substrate within the processing container, An upper member provided opposite the aforementioned mounting base, forming a processing space between it and the aforementioned mounting base, A gap control unit that controls the gap between the mounting base and the upper member, A flow straightening member provided around the processing space, Equipped with, The rectifying member has an opening that allows at least a portion of the gas flowing out of the processing space to pass through, The gap control unit is A first control that controls the spacing of the gaps so that the spacing of the gaps is the same as or less than the height of the opening, A second control that controls the gap so that the gap is greater than the height of the opening and the lower end of the upper member is lower than the upper end of the rectifying member, A third control that controls the gap spacing such that the lower end of the upper member is higher than the upper end of the rectifying member, Execute Control method.

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