Substrate mounting stage, substrate processing apparatus and substrate processing method (I)

Abstract

This disclosure provides a substrate mounting stage, a substrate processing apparatus, and a substrate processing method for suppressing uneven substrate processing at positions corresponding to lifting pins. A substrate mounting stage has a mounting surface for mounting a substrate; the substrate mounting stage comprises: a substrate; lifting pins, made of conductor, that move up and down relative to the mounting surface, having a step between an upper and lower portion, and the diameter of the upper portion being larger than the diameter of the lower portion; a pin hole opening in the mounting surface to allow the lifting pin, formed inside the substrate, to pass through; and a retainer, comprising a through hole through which the lifting pin passes, disposed in the substrate, and made of conductor; the retainer comprises an outer retainer and an inner retainer; the through hole is formed on the central axis of the inner retainer, allowing the lifting pin to move up and down; the inner diameter of the through hole is smaller than the diameter of the upper portion of the lifting pin; the inner retainer is slidably supported on the outer retainer by an elastic member disposed between the inner and outer retainers.

Description

Technical Field

[0001] The present disclosure relates to a substrate mounting platform, a substrate processing device, and a substrate processing method. Prior Art

[0002] Patent Document 1 discloses a substrate mounting table capable of suppressing uneven processing of the mounting table body at positions corresponding to insertion holes of lift pins when performing plasma processing on a substrate.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2007-273685 Summary of the Invention

[0004] The present disclosure provides a substrate mounting table, a substrate processing apparatus, and a substrate processing method for preventing substrate processing from becoming uneven at positions corresponding to lift pins.

[0005] According to one aspect of the present disclosure, a substrate loading platform is provided, which has a loading surface for loading a substrate; the substrate loading platform comprises: a substrate, which is located below the loading surface and is composed of a conductor; a lifting pin, which is composed of a conductor and is lifted and lowered relative to the loading surface, has a step difference between the upper and lower parts, and the diameter of the upper part is larger than the diameter of the lower part; a pin hole, which is open in the loading surface and allows the lifting pin formed inside the substrate to appear and retract; and a holder, which includes a through hole through which the lifting pin can pass, is arranged on the substrate and is composed of a conductor; the holder comprises an outer holder and an inner holder with a common central axis; the through hole is formed on the central axis of the inner holder and allows the lifting pin to move up and down; the inner diameter of the through hole is smaller than the diameter of the upper part of the lifting pin; the inner holder is slidably supported on the outer holder through an elastic member arranged between the inner holder and the outer holder.

[0006] According to the present disclosure, a substrate mounting table, a substrate processing device and a substrate processing method can be provided, which can suppress the substrate processing from becoming uneven at positions corresponding to lift pins. Simple diagram description

[0007] FIG. 1 is a cross-sectional view showing a substrate processing apparatus equipped with a substrate mounting table according to the present embodiment. FIG2 is an enlarged cross-sectional view of the substrate mounting table related to this embodiment. FIG3 is an enlarged cross-sectional view of the substrate mounting table related to this embodiment. FIG. 4 is a partial side view of lift pins provided on the substrate mounting table according to the present embodiment. FIG5 is an enlarged cross-sectional view of a holder included in the substrate mounting table according to the present embodiment. FIG6 is a flow chart illustrating a substrate processing method using a substrate processing apparatus equipped with a substrate mounting table according to the present embodiment. Implementation Method

[0008] In the following, the embodiments of the present disclosure are described with reference to the drawings. In addition, in this specification and drawings, substantially the same components are denoted by the same reference numerals to omit repeated descriptions.

[0009] Deviations in parallel, right-angled, orthogonal, horizontal, vertical, up-down, left-right, and other directions are permitted without compromising the effectiveness of the implementation. Corner shapes are not limited to right angles and may also be rounded. Parallel, right-angled, orthogonal, horizontal, and vertical may also include approximately parallel, approximately right-angled, approximately orthogonal, approximately horizontal, and approximately vertical.

[0010] 1 is a cross-sectional view of a substrate processing apparatus 1 including a substrate mounting table 20 according to this embodiment. The substrate processing apparatus 1 is, for example, a plasma etching apparatus, or a capacitively coupled parallel plate plasma etching apparatus.

[0011] The substrate processing apparatus 1 is an apparatus for etching a glass substrate G for a flat panel display (FPD). Examples of flat panel displays include liquid crystal displays, light emitting diode displays, electroluminescent displays, fluorescent displays, and plasma displays.

[0012] The substrate processing apparatus 1 includes a processing container 10 , a substrate mounting table 20 , a power supply unit 30 , a gas supply unit 40 , and an exhaust unit 50 .

[0013] [Processing container 10] The processing container 10 is a so-called processing chamber. The processing container 10 is formed of, for example, aluminum or an aluminum alloy with an anodized surface. The processing container 10 has a square cylindrical shape.

[0014] The processing container 10 includes a shower head 11 at its top. The shower head 11 is parallel to and faces the substrate mounting table 20 and functions as an upper electrode. The shower head 11 also supplies gas to the processing space 10S of the processing container 10.

[0015] The shower head 11 is disposed above the substrate mounting table 20. The shower head 11 is supported on the upper portion of the processing container 10. The shower head 11 is grounded. The shower head 11 and the substrate mounting table 20 together form a pair of parallel plate electrodes.

[0016] The shower head 11 has an internal space 11 a therein and a plurality of ejection holes 11 b on a surface facing the substrate mounting table 20 for ejecting a processing gas.

[0017] A gas inlet port 11 c is provided on the upper surface of the shower head 11 . The gas inlet port 11 c is connected to a process gas supply pipe 40 p . The process gas supply pipe 40 p is connected to the gas supply unit 40 .

[0018] The processing chamber 10 includes a partition member 12 on the bottom wall 10a for mounting a substrate stage 20. The partition member 12 is formed of an insulator and is configured to conform to the outer shape of the substrate stage 20. The substrate stage 20 is mounted on the partition member 12. The substrate stage 20 comprises a main body 21 and an insulating member 22.

[0019] The spacer 12 and bottom wall 10a, as well as the spacer 12, main body 21, and insulating member 22 are hermetically sealed. Thus, a space 10A containing an atmospheric atmosphere is formed between the main body 21 and bottom wall 10a of the substrate mounting table 20. This space 10A provides insulation from the atmosphere.

[0020] The processing chamber 10 includes a plurality of insulating members 13. The insulating members 13 are embedded in the bottom wall 10a of the processing chamber 10. Bolts 14 are inserted into through-holes vertically provided in the center of the insulating members 13. The main body 21 of the substrate stage 20 is secured to the bottom wall 10a by the bolts 14. By securing the main body 21 to the bottom wall 10a using the plurality of bolts 14, the substrate stage 20 is prevented from deflecting due to the pressure differential between the processing space 10S, which has a vacuum atmosphere, and the space 10A, which has an atmospheric atmosphere, even when the processing chamber 10 is maintained in a vacuum state.

[0021] The processing container 10 includes an exhaust pipe 15 connected to the bottom wall 10a. The exhaust pipe 15 is connected to an exhaust unit 50. The exhaust unit 50 exhausts the processing space 10S of the processing container 10. The exhaust unit 50 evacuates the processing space 10S of the processing container 10 to a predetermined reduced pressure atmosphere.

[0022] The processing chamber 10 includes a substrate transfer port 16 and a gate valve 17 for opening and closing the substrate transfer port 16 on a side wall. The substrate processing apparatus 1 transfers a glass substrate G to an adjacent load lock chamber (not shown) with the gate valve 17 open.

[0023] [Substrate mounting table 20] The substrate processing apparatus 1 includes a substrate mounting table 20 at the bottom of a processing container 10 for mounting a glass substrate G, serving as a substrate to be processed. The substrate mounting table 20 mounts the glass substrate G on a mounting surface 20S. Specifically, the substrate mounting table 20 has a mounting surface 20S. The substrate mounting table 20 is disposed within the processing container 10.

[0024] The substrate stage 20 includes a main body 21, an insulating member 22, and a plurality of substrate lifts 23. Figures 2 and 3 are enlarged cross-sectional views of the substrate stage 20 according to this embodiment. Specifically, Figures 2 and 3 are enlarged cross-sectional views of a portion of the substrate lift 23 in the substrate stage 20. Figure 2 shows a state in which a glass substrate G is placed on the substrate stage 20 and the lift pins 23a are retracted into the interior of the substrate stage 20. The state in Figure 2 is referred to as the retracted state. Figure 3 shows a state in which the glass substrate G is lifted from the substrate stage 20 by the lift pins 23a. The state in Figure 3 is referred to as the supported state.

[0025] (Main part 21) The main body 21 functions as a lower electrode by receiving high-frequency power from the power supply unit 30 .

[0026] The main body 21 includes a substrate 21a, a dielectric layer 21b, a plurality of protrusions 21c, and a raised portion 21d. The raised portion 21d protrudes upward from the dielectric layer 21b at the peripheral edge of the upper surface of the main body 21, forming a frame-like shape. The main body 21 includes pin holes 21h for allowing the lift pins 23a of the substrate lift unit 23 to enter and exit. The pin holes 21h are provided to penetrate the substrate 21a and the dielectric layer 21b. The pin holes 21h open onto the mounting surface 20S. The mounting surface 20S also includes a plurality of cooling gas holes (not shown) for supplying a cooling gas (return cooling gas) such as helium. The cooling gas, such as helium, is supplied between the mounting surface 20S and the lower surface (inner surface) of the glass substrate G, exchanging heat with the glass substrate G to adjust the temperature of the glass substrate G.

[0027] The substrate 21a is composed of a conductive member, i.e., a conductor. The substrate 21a is formed, for example, from metal. Specifically, the substrate 21a is formed from, for example, aluminum, an aluminum alloy, a stainless steel alloy, or a combination of an aluminum alloy and a stainless steel alloy. The substrate 21a is positioned below the mounting surface 20S. The substrate lift 23 is attached to the substrate 21a.

[0028] The main body 21 includes a dielectric layer 21b on top of a base material 21a. Dielectric layer 21b is formed from a dielectric material such as ceramic. Electrode 21b1 for electrostatic attraction is embedded within dielectric layer 21b. Electrode 21b1 serves as an electrostatic attraction electrode. A voltage is applied to electrode 21b1 from an external power source (not shown). This voltage is applied to electrode 21b1, which attracts the glass substrate G via Coulomb force. Electrode 21b1 is formed from, for example, tungsten.

[0029] Furthermore, the substrate 21a has a flow channel (not shown) inside. By flowing a heat medium set to a predetermined temperature through the flow channel of the substrate 21a, the temperature of the substrate 21a is adjusted to a predetermined desired temperature.

[0030] The main body 21 includes a plurality of protrusions 21c and raised portions 21d on the upper portion of the dielectric layer 21b. The protrusions 21c and raised portions 21d are formed, for example, from a dielectric material. The protrusions 21c are formed as projections on the upper portion of the dielectric layer 21b, while the raised portions 21d are provided on the peripheral edge of the upper portion of the dielectric layer 21b. The upper surface of the raised portions 21d and the upper surface of the protrusions 21c are either higher than or the same height as the upper surface of the protrusions 21c. When a glass substrate G is placed on the substrate mounting table 20, the glass substrate G comes into contact with the upper surface of the protrusions 21d, or with both the upper surface of the protrusions 21d and the upper surface of the protrusions 21c. The main body 21 does not necessarily need to include a plurality of protrusions 21c; the area inside the protrusions 21d may be flat. Furthermore, the area inside the protrusions 21d may be flat, or it may be roughened.

[0031] (Insulating member 22) The substrate mounting table 20 includes an insulating member 22 disposed so as to surround the periphery of the substrate 21a. The upper surface of the insulating member 22 is slightly lower than the upper surface of the raised portion 21d of the main body 21, leaving a gap (e.g., approximately 0.1 mm to 0.3 mm) between the insulating member 22 and the glass substrate G. The insulating member 22 may also be divided into multiple components, such as an upper component and a lower component.

[0032] (Substrate lifting unit 23) When loading and unloading the glass substrate G onto the substrate stage 20, the substrate lifting unit 23 moves the glass substrate G away from the substrate stage 20 and supports it above the substrate stage 20. The glass substrate G supported away from the substrate stage 20 is carried in and out by the conveying device.

[0033] The substrate lift 23 is inserted from the outside of the bottom wall 10a into the processing container 10. The substrate lift 23 includes lift pins 23a, a holder 23b, a biasing member 23c, an O-ring 23d, a connecting portion 23e, and a lift portion 23f.

[0034] (Lifting pin 23a) The lift pins 23a support the glass substrate G. The lift pins 23a also lift the glass substrate G. The lift pins 23a appear and disappear in the pin holes 21h formed in the main body 21. The lift pins 23a are formed of a conductive member.

[0035] 4 is a partial side view of the lift pin 23a included in the substrate mounting table 20 according to this embodiment. The lift pin 23a has an upper portion 23a1, an inclined portion 23a2, and a lower portion 23a3. The lift pin 23a has a rotationally symmetrical shape with respect to the central axis AX.

[0036] The upper portion 23a1 of the lift pin 23a has a cylindrical shape with a central axis AX and a diameter D2. The diameter D2 of the upper portion 23a1 is smaller than the diameter D1 of the pin hole 21h. Therefore, even when the lift pin 23a moves vertically, it does not contact the inner surface of the pin hole 21h. This prevents the generation of particles, etc., caused by the lift pin 23a contacting the inner surface of the pin hole 21h.

[0037] When the lift pins 23a ascend, the lift pins 23a support the glass substrate G with the upper surface 23aA of the upper portion 23a1. In other words, the upper surface 23aA of the upper portion 23a1 serves as a support surface for the glass substrate G. The lift pins 23a can contact the glass substrate G with the upper surface 23aA of the upper portion 23a1.

[0038] Side 23aB of lift pin 23a serves as a sealing surface for contact with O-ring 23d. When lift pin 23a is in the retracted position (see Figure 2), side 23aB of upper portion 23a1 contacts O-ring 23d. This contact between side 23aB of lift pin 23a and O-ring 23d maintains an airtight seal between lift pin 23a and O-ring 23d. In other words, contact between side 23aB of lift pin 23a and O-ring 23d ensures airtightness between lift pin 23a and retainer 23b.

[0039] For example, a cooling gas (return gas) such as helium may be circulated between the lower surface (inner surface) of the glass substrate G and the mounting surface 20S. By ensuring airtightness between the lift pins 23a and the holder 23b, leakage of the cooling gas below the pin holes 21h can be suppressed. By suppressing leakage of the cooling gas, temperature stability can be improved.

[0040] The inclined portion 23a2 of the lift pin 23a connects the upper portion 23a1 and the lower portion 23a3, which have different outer diameters. The inclined portion 23a2 connects the step between the upper portion 23a1 and the lower portion 23a3. The inclined portion 23a2 has a symmetrical shape with respect to the central axis AX. The inclined portion 23a2 has a truncated conical shape with a larger upper surface and a smaller lower surface.

[0041] The inclined portion 23a2 has a side surface 23aC. When the lift pin 23a is in the retracted state (see Figure 2), the side surface 23aC contacts the inclined surface 23nA (see Figure 5) of the inner retainer 23n of the retainer 23b. The contact between the side surface 23aC and the inclined surface 23nA establishes electrical continuity between the lift pin 23a and the retainer 23b. This electrical continuity between the lift pin 23a and the retainer 23b brings the substrate 21a and the lift pin 23a into electrical contact and into the same potential. By aligning the substrate 21a and the lift pin 23a, the potential distribution on the mounting surface 20S of the substrate mounting table 20 is uniform.

[0042] Furthermore, when the lift pins 23a are in the supporting position (see Figure 3), the side surfaces 23aC separate from the inclined surfaces 23nA of the inner holder 23n of the holder 23b. Separating the side surfaces 23aC from the inclined surfaces 23nA electrically separates the lift pins 23a from the holder 23b. This electrically separates the lift pins 23a from the holder 23b, insulating the substrate 21a from the lift pins 23a. This insulation between the substrate 21a and the lift pins 23a prevents abnormal discharge when, for example, a charged glass substrate G is removed from the substrate stage 20 while being de-electrified by the de-electrifying plasma.

[0043] The lower portion 23a3 of the lift pin 23a has a cylindrical shape with a central axis AX and a diameter D3. The diameter D3 of the lower portion 23a3 is smaller than the inner diameter of the O-ring 23d. Therefore, when the lift pin 23a is in the supported position (see Figure 3), the side surface 23aD of the lower portion 23a3 does not contact the inner surface of the O-ring 23d. This prevents the generation of particles and the like due to contact with the O-ring 23d during movement of the lift pin 23a.

[0044] (Retainer 23b) The holder 23b holds the lift pin 23a in a manner that allows it to be raised and lowered. The holder 23b includes an outer holder 23m and an inner holder 23n.

[0045] FIG5 is an enlarged cross-sectional view of the holder 23b included in the substrate mounting table 20 according to this embodiment. The outer holder 23m and the inner holder 23n share a common central axis BX. The outer holder 23m and the inner holder 23n have rotationally symmetrical shapes with respect to the central axis BX.

[0046] The outer retainer 23m is embedded in the recess 21ah provided on the bottom surface of the substrate 21a. The outer retainer 23m is formed from a conductive member. The outer retainer 23m is formed, for example, from aluminum or an aluminum alloy. The outer retainer 23m is electrically connected to the substrate 21a. The top surface 23mA and side surfaces 23mB of the outer retainer 23m contact the inner surface of the recess 21ah. By bringing the top surface 23mA and side surfaces 23mB of the outer retainer 23m into contact with the inner surface of the recess 21ah, the outer retainer 23m and the substrate 21a are electrically connected.

[0047] The outer holder 23m has an upper portion 23ma, a cylindrical portion 23mb, and a lower portion 23mc. The interior of the outer holder 23m is hollow. The outer holder 23m holds the inner holder 23n and the biasing member 23c therein.

[0048] The upper portion 23ma is disk-shaped with an opening 23mh. The diameter of the opening 23mh is equal to the diameter D1 of the pinhole 21h. Alternatively, the diameter of the opening 23mh may be larger than the diameter D1. The upper portion 23ma has a groove 23mg for retaining an O-ring 23d. The O-ring 23d is located in the groove 23mg.

[0049] The cylindrical portion 23mb has a cylindrical shape. The inner surface 23mC of the cylindrical portion 23mb contacts the outer surface 23nB of the inner retainer 23n. The contact between the inner surface 23mC and the outer surface 23nB creates electrical continuity between the outer retainer 23m and the inner retainer 23n. The inner retainer 23n moves relative to the outer retainer 23m. Therefore, to facilitate sliding between the inner surface 23mC and the outer surface 23nB, a metal film containing a fluorine-based resin is formed on the inner surface 23mC. For example, nickel or platinum is used as the metal film.

[0050] The lower portion 23mc is disk-shaped with an opening 23mi. The diameter of the opening 23mi of the lower portion 23mc is equal to the outer diameter of the cylindrical portion 23nb of the inner retainer 23n. The inner surface 23mD of the lower portion 23mc contacts the outer surface 23nC of the inner retainer 23n. By bringing the inner surface 23mD and the outer surface 23nC into contact, electrical connection is established between the outer retainer 23m and the inner retainer 23n. The inner retainer 23n moves relative to the outer retainer 23m. Therefore, to facilitate sliding between the inner surface 23mD and the outer surface 23nC, a metal film containing a fluorine-based resin is formed on the inner surface 23mD. For example, nickel or platinum is used as the metal film.

[0051] The inner retainer 23n is disposed inside the outer retainer 23m. The inner retainer 23n is slidably supported on the outer retainer 23m. The inner retainer 23n is configured to be movable in the vertical direction relative to the outer retainer 23m, that is, to be movable up and down. The inner retainer 23n is formed from a conductive member. The inner retainer 23n is formed, for example, from aluminum or an aluminum alloy.

[0052] The inner retainer 23n has a through-hole 23nh extending vertically. The through-hole 23nh is formed on the central axis of the inner retainer 23n, in other words, on the central axis BX. The inner diameter of the through-hole 23nh is larger than the diameter D3 of the lower portion 23a3 of the lift pin 23a to enable the lift pin 23a to move vertically. Furthermore, the inner diameter of the through-hole 23nh is smaller than the diameter D2 of the upper portion 23a1 of the lift pin 23a. The inner retainer 23n includes an upper portion 23na and a cylindrical portion 23nb.

[0053] The upper portion 23na has an inclined surface 23nA at the upper end above the through-hole 23nh. When the lift pin 23a is in the retracted position (see Figure 2), the inclined surface 23nA contacts the side surface 23aC of the lift pin 23a. The contact between the inclined surface 23nA and the side surface 23aC establishes electrical continuity between the lift pin 23a and the holder 23b. This electrical continuity between the lift pin 23a and the holder 23b establishes electrical continuity between the substrate 21a and the lift pin 23a, bringing them to the same potential. By aligning the potential between the substrate 21a and the lift pin 23a, the potential distribution within the substrate stage 20 is uniform.

[0054] The outer diameter of the upper portion 23na is equal to the diameter of the inner surface 23mC of the cylindrical portion 23mb of the outer retainer 23m. Consequently, the outer surface 23nB, which is the side surface of the upper portion 23na, contacts the inner surface 23mC of the cylindrical portion 23mb. This contact between the outer surface 23nB and the inner surface 23mC establishes electrical continuity between the outer retainer 23m and the inner retainer 23n. The inner retainer 23n moves relative to the outer retainer 23m. Therefore, to facilitate sliding between the inner surface 23mC and the outer surface 23nB, a metal film containing a fluorine-based resin is formed on the outer surface 23nB. For example, nickel or platinum is used as the metal film.

[0055] Furthermore, a biasing member 23c is provided between the upper portion 23na and the lower portion 23mc of the outer retainer 23m. The biasing member 23c biases the inner retainer 23n upward. In the retracted state (see Figure 2), when the lift pin 23a is lowered, the lift pin 23a and the inner retainer 23n come into contact. By biasing the inner retainer 23n upward with the biasing member 23c, the lift pin 23a and the inner retainer 23n can be brought into contact while maintaining a predetermined pressing force. By maintaining the predetermined pressing force while maintaining the lift pin 23a and the inner retainer 23n, sufficient electrical continuity between the lift pin 23a and the inner retainer 23n is ensured.

[0056] Furthermore, the inner holder 23n is urged upward by the urging member 23c, so that when the inner holder 23n is moved and brought into contact with the inner holder 23n by the lifting pin 23a, the inner holder 23n can be moved.

[0057] The cylindrical portion 23nb has a cylindrical shape. The outer surface 23nC of the cylindrical portion 23nb contacts the inner surface 23mD of the outer retainer 23m. The contact between the outer surface 23nC and the inner surface 23mD creates electrical continuity between the outer retainer 23m and the inner retainer 23n. The inner retainer 23n moves relative to the outer retainer 23m. Therefore, to facilitate sliding between the outer surface 23nC and the inner surface 23mD, a metal film containing a fluorine-based resin is formed on the outer surface 23nC. For example, nickel or platinum is used as the metal film.

[0058] 5, the portion where the outer holder 23m and the inner holder 23n are in contact and electrically connected is shown surrounded by a dotted oval.

[0059] (Force applying member 23c) The biasing member 23c biases the inner retainer 23n upward. The biasing member 23c is an elastic member. For example, the biasing member 23c is a coil spring. The biasing member 23c is positioned between the outer retainer 23m and the inner retainer 23n. More specifically, the biasing member 23c is positioned between the lower portion 23mc of the outer retainer 23m and the upper portion 23na of the inner retainer 23n. The biasing member 23c can also be formed from a conductor. By forming the biasing member 23c from a conductor, the conduction between the outer retainer 23m and the inner retainer 23n can be enhanced through the biasing member 23c.

[0060] (O-ring 23d) The O-ring 23d ensures an airtight seal between the lift pin 23a and the retainer 23b. The O-ring 23d is located in the annular groove 23mg of the outer retainer 23m. When the lift pin 23a is in the retracted position, the O-ring 23d is interposed between the upper portion 23a1 of the lift pin 23a and the annular groove 23mg. By interposing the O-ring 23d between the upper portion 23a1 of the lift pin 23a and the annular groove 23mg, the O-ring 23d ensures an airtight seal between the lift pin 23a and the retainer 23b.

[0061] (Connection portion 23e) The connecting portion 23e connects the main body 21 and the lifting portion 23f. The connecting portion 23e is formed of, for example, a telescopic tube. The connecting portion 23e is formed of a conductive member.

[0062] (Lifting portion 23f) The lifting unit 23f moves the lifting pin 23a in the vertical direction. The lifting unit 23f is composed of, for example, a motor. The lifting unit 23f moves the lifting pin 23a in the vertical direction by driving the motor.

[0063] The lifting portion 23f adjusts the distance between the upper surface 23aA of the upper end of the lift pin 23a and the mounting surface 20S. In other words, the lifting portion 23f adjusts the distance between the upper surface 23aA of the lift pin 23a and the mounting surface 20S. By adjusting the distance between the upper surface 23aA of the lift pin 23a and the mounting surface 20S, the electric field distribution can be adjusted. For example, the upper portion 23a1 of the lift pin 23a is adjusted so that it is located near the glass substrate G. Specifically, the distance between the upper portion 23a1 of the lift pin 23a and the mounting surface 20S on which the glass substrate is mounted is adjusted to a value between 0.02 mm and 0.2 mm, for example, 0.06 mm. Furthermore, when adjusting the distance, the adjustment is performed so that the side surface 23aC of the inclined portion 23a2 of the lift pin 23a contacts the inclined surface 23nA of the upper end of the inner retainer 23n. That is, the adjustment is performed in a state where the biasing member 23c pushes the inner retainer 23n so that the inclined surface 23nA contacts the side surface 23aC and presses the side surface 23aC.

[0064] [Power supply unit 30] The power supply unit 30 supplies high-frequency power to the substrate 21a on the substrate mounting table 20. The power supply unit 30 is connected to the substrate 21a via a power supply line 30w. The power supply unit 30 includes high-frequency power sources 31a and 31b, and matching units 32a and 32b. The power supply line 30w branches into a power supply line 30wa and a power supply line 30wb. The branched power supply line 30wa is connected to the matching unit 32a. The branched power supply line 30wb is connected to the matching unit 32b.

[0065] High-frequency power supply 31a is a high-frequency power supply for plasma generation. The frequency of the high-frequency power generated by high-frequency power supply 31a is, for example, 13.56 MHz. High-frequency power supply 31a outputs the high-frequency power to matching device 32a. Matching device 32a performs impedance matching and outputs the high-frequency power for plasma generation to substrate 21a via power supply lines 30wa and 30w.

[0066] High-frequency power supply 31b is a high-frequency power supply for bias generation. The frequency of the high-frequency power generated by high-frequency power supply 31b is, for example, 3.2 MHz. High-frequency power supply 31b outputs the high-frequency power to matching device 32b. Matching device 32b achieves impedance matching and outputs the high-frequency power for bias generation to substrate 21a via power supply lines 30wb and 30w.

[0067] [Gas supply unit 40] The gas supply unit 40 supplies a processing gas for processing the glass substrate G to the processing container 10 . The gas supply unit 40 includes a processing gas supply source 41 , a mass flow controller 42 , and a valve 43 .

[0068] The processing gas supply source 41 supplies gases for processing the glass substrate G. For example, the processing gas supply source 41 supplies halogen gas, oxygen gas, argon gas, or other gases commonly used in the field as processing gases for etching metal films, silicon oxide films, silicon nitride films, and the like formed on the glass substrate G.

[0069] The mass flow controller 42 adjusts the flow rate of the process gas supplied from the process gas supply source 41. The process gas whose flow rate is adjusted by the mass flow controller 42 passes through the valve 43 and is supplied to the shower head 11 via the process gas supply pipe 40p.

[0070] [Exhaust section 50] The exhaust unit 50 exhausts the processing space 10S of the processing container 10. The exhaust unit 50 includes a vacuum pump 51. The vacuum pump 51 is connected to the exhaust pipe 15. The vacuum pump 51 is, for example, a turbomolecular pump.

[0071] In addition, the power supply unit 30 and the gas supply unit 40 may be collectively referred to as a plasma generation unit.

[0072] <Substrate Processing Method> A substrate processing method using a substrate processing apparatus 1 equipped with a substrate mounting table 20 according to this embodiment will be described. FIG6 is a flow chart illustrating the substrate processing method using a substrate processing apparatus 1 equipped with a substrate mounting table 20 according to this embodiment. FIG6 will further explain the steps of the substrate processing method according to this embodiment in detail.

[0073] (Step S10) After the processing starts, the glass substrate G is loaded into the processing container 10 of the substrate processing apparatus 1. Specifically, with the gate valve 17 open, the glass substrate G is loaded into the processing container 10 from the substrate loading / unloading port 16 by the loading / unloading device.

[0074] (Step S20) Next, the lift pins 23a are raised to protrude from the placement surface 20S. The carried glass substrate G is then placed on the support surface of the protruding lift pins 23a. The glass substrate G is then supported by the lift pins 23a.

[0075] The conveying device after loading the glass substrate G is withdrawn from the processing container 10. Then, the gate valve 17 is closed.

[0076] (Step S30) Next, the lift pins 23a are lowered and received in the pin holes 21h. After the lift pins 23a are lowered and received in the pin holes 21h, the glass substrate G is placed on the convex portions 21c and the raised portions 21d. By placing the glass substrate G on the convex portions 21c and the raised portions 21d, the glass substrate G is placed on the placement surface 20S.

[0077] (Step S40) Next, the lift pin 23a is brought into contact with the inner retainer 23n. The lift pin 23a is lowered and accommodated in the pin hole 21h. After the lift pin 23a is lowered and accommodated in the pin hole 21h, the side surface 23aC of the lift pin 23a comes into contact with the inclined surface 23nA of the inner retainer 23n. When the side surface 23aC of the lift pin 23a comes into contact with the inclined surface 23nA of the inner retainer 23n, electrical continuity is established between the lift pin 23a and the inner retainer 23n. In other words, when the lift pin 23a comes into contact with the inner retainer 23n, electrical continuity is established between the lift pin 23a and the inner retainer 23n. By establishing electrical continuity between the lift pin 23a and the inner retainer 23n, electrical continuity is established between the lift pin 23a and the substrate 21a.

[0078] (Step S50) Next, the glass substrate G is subjected to a plasma treatment. In other words, the glass substrate G is treated using plasma. Specifically, the plasma treatment is performed by supplying a process gas from the gas supply unit 40 and power from the power supply unit 30. After the plasma treatment is completed, the process gas is exhausted by the exhaust unit 50.

[0079] (Step S60) After the plasma treatment of the glass substrate G is completed, the lift pins 23a are raised to protrude from the mounting surface 20S. Then, the protruding lift pins 23a lift the glass substrate G that has been subjected to the plasma treatment.

[0080] (Step S70) Next, the glass substrate G is unloaded from the processing container 10 of the substrate processing apparatus 1. Specifically, with the gate valve 17 open, the transfer device is allowed to enter the processing container 10 through the substrate transfer inlet 16. The glass substrate G is then placed on the transfer device and unloaded from the processing container 10.

[0081] According to the substrate mounting table 20 of this embodiment, during plasma processing, it is possible to suppress uneven electric field formation in the substrate mounting table 20, which functions as a lower electrode. According to the substrate mounting table 20 of this embodiment, by suppressing uneven electric field formation, it is possible to suppress uneven substrate processing at positions corresponding to the lift pins.

[0082] In the substrate processing apparatus 1, the substrate stage 20 of this embodiment functions as a lower electrode during plasma processing. The substrate stage 20, also serving as the lower electrode, includes lift pins 23a for raising and lowering a glass substrate G, for example. To enable the lift pins 23a to move vertically, the base 21a of the substrate stage 20 has pin holes 21h.

[0083] Because the substrate 21a has pin holes 21h, when the substrate mounting table 20 functions as a lower electrode, the electric field may become non-uniform in the pin holes 21h. According to the substrate mounting table 20 of this embodiment, by providing electrical continuity between the lift pins 23a housed within the pin holes 21h and the substrate 21a, this non-uniform electric field in the pin holes 21h can be suppressed.

[0084] Specifically, the substrate mounting table 20 according to this embodiment includes a lift pin 23a formed of a conductive member in a pin hole 21h. Furthermore, the substrate mounting table 20 according to this embodiment has a structure in which a holder 23b formed of a conductive member is provided in the portion of the substrate 21a that communicates with the pin hole 21h. Furthermore, the lift pin 23a has an inclined portion 23a2 with a stepped diameter, with a larger diameter at an upper portion 23a1 and a smaller diameter at a lower portion 23a3. When the lift pin 23a is accommodated, the lift pin 23a and the holder 23b come into contact at a side surface 23aC of the inclined portion 23a2.

[0085] The retainer 23b is composed of a coaxial outer retainer 23m and an inner retainer 23n. The inclined surface 23nA located on the upper portion 23na of the inner retainer 23n contacts the inclined portion 23a2 when the lift pin 23a is accommodated. Furthermore, the inner retainer 23n is supported on the outer retainer 23m via a biasing member 23c. By supporting the inner retainer 23n on the outer retainer 23m via the biasing member 23c, the inner retainer 23n is movable vertically. By allowing the inner retainer 23n to move vertically, the height of the tip of the lift pin 23a when accommodated can be adjusted.

[0086] Furthermore, by making the middle portion of the lift pin 23a electrically conductive with the substrate 21a, the capacitance component can be reduced compared to when the lower end of the lift pin 23a is electrically conductive with the substrate 21a. Furthermore, when the lift pin 23a is housed, sufficient space is left for adjusting the height of the lift pin 23a, making height adjustment easy.

[0087] In addition, although the above description has been made on the case where the glass substrate G is processed, the substrate to be processed is not limited to a glass substrate, and may also be a substrate such as a semiconductor substrate formed of silicon, gallium, or an alloy thereof.

[0088] The substrate mounting table, substrate processing device, and substrate processing method related to the present embodiment disclosed in this specification should be considered in all respects to be merely illustrative and not intended to limit the contents of the present invention. For example, although the above description has described the case where a capacitively coupled parallel plate plasma etching device is used as the substrate processing device, it can also be another type of plasma device such as an inductively coupled plasma device. In addition, substrate processing is not limited to etching processing, and can also be other substrate processing such as film forming processing or ashing processing. The above embodiment can be deformed and improved in various forms without departing from the scope of the patent application and its gist. The matters recorded in the above multiple embodiments can also adopt other structures within the scope of no contradiction, and can also be combined within the scope of no contradiction.

[0089] 1: Substrate processing equipment 10: Processing Containers 20: substrate mounting table 20S: Loading surface 21: Ontology part 21a: substrate 21h: Pin hole 23: Substrate lifting unit 23a: Lifting pin 23b: Retainer 23m: Outer retainer 23n: medial retainer 23nh:Through hole 23c: Force-applying member 23d: O-ring 30: Power supply unit 40: Gas supply department AX: Center axis BX: Center axis

Claims

1. A substrate mounting stage having a mounting surface for mounting a substrate; the substrate mounting stage comprising: a substrate, located below the mounting surface, and made of a conductor; a lifting pin, also made of a conductor, capable of moving up and down relative to the mounting surface, having a step between its upper and lower portions, and the diameter of the upper portion being larger than the diameter of the lower portion; a pin hole, opening in the mounting surface to allow the lifting pin formed inside the substrate to move in and out; and a retainer, comprising a through hole through which the lifting pin passes, disposed in the substrate and made of a conductor; the retainer comprising an outer retainer and an inner retainer having a common central axis; the through hole being formed on the central axis of the inner retainer to allow the lifting pin to move up and down; the inner diameter of the through hole being smaller than the diameter of the upper portion of the lifting pin; and the inner retainer being slidably supported on the outer retainer by an elastic member disposed between the inner and outer retainers.

2. As in the substrate mounting stage of claim 1, when the lifting pin is received in the pin hole, the step of the lifting pin is connected to the upper end of the through hole of the inner retainer, and the lifting pin is electrically connected to the substrate through the inner retainer and the outer retainer.

3. The substrate mounting stage as described in claim 2 can adjust the distance between the upper end of the lifting pin and the mounting surface while the step of the lifting pin is in contact with the upper end of the inner retainer.

4. The substrate mounting stage of any one of claims 1 to 3 has a dielectric layer on the upper part of the substrate in which electrostatic adsorption electrodes are embedded; the upper part of the dielectric layer is the mounting surface.

5. The substrate mounting stage of any one of the claims 1 to 3 further comprises an O-ring, which, when the lifting pin is received in the pin hole, keeps the outer side sealed with the upper part of the lifting pin.

6. A substrate processing apparatus for processing a substrate inside a processing container; the substrate processing apparatus comprising: a substrate mounting stage disposed inside the processing container for mounting the substrate; and a plasma generation unit for generating plasma for processing the substrate inside the processing container; the substrate mounting stage having a mounting surface for mounting the substrate comprises: a substrate located below the mounting surface and made of a conductor; a lifting pin made of a conductor that moves up and down relative to the mounting surface, having a step between its upper and lower portions, and the diameter of the upper portion being larger than the diameter of the lower portion; a pin hole opening in the mounting surface to allow the lifting pin formed inside the substrate to move in and out; and a retainer comprising a through hole through which the lifting pin passes, disposed in the substrate and made of a conductor; the retainer comprising an outer retainer and an inner retainer having a common central axis; the through hole being formed on the central axis of the inner retainer to allow the lifting pin to move up and down; The inner diameter of the through hole is smaller than the diameter of the upper part of the lifting pin; the inner retainer is slidably supported on the outer retainer by an elastic member disposed between the inner and outer retainers.

7. The substrate processing apparatus of claim 6, wherein when the lifting pin is received in the pin hole, the step of the lifting pin is connected to the upper end of the through hole of the inner retainer, and the lifting pin is electrically connected to the substrate through the inner retainer and the outer retainer.

8. The substrate processing apparatus of claim 7, wherein the distance between the upper end of the lifting pin and the mounting surface can be adjusted while the step of the lifting pin is in contact with the upper end of the inner retainer.

9. The substrate processing apparatus of any one of claims 6 to 8, wherein a dielectric layer on the upper part of the substrate is provided with an electrostatic adsorption electrode; the upper surface of the dielectric layer is the mounting surface.

10. The substrate processing apparatus of any one of claims 6 to 8 further comprises an O-ring that, when the lifting pin is received in the pin hole, keeps the outer side sealed with the upper part of the lifting pin.

11. A substrate processing method, wherein a substrate is processed inside a processing container of a substrate processing apparatus; the substrate processing apparatus comprises: a substrate mounting stage disposed inside the processing container for mounting the substrate; and a plasma generation unit that generates plasma for processing the substrate inside the processing container; the substrate mounting stage having a mounting surface for mounting the substrate comprises: a substrate located below the mounting surface and made of a conductor; a lifting pin made of a conductor that moves up and down relative to the mounting surface, having a step between its upper and lower portions, and the diameter of the upper portion being larger than the diameter of the lower portion; a pin hole opening in the mounting surface to allow the lifting pin formed inside the substrate to move in and out; and a retainer comprising a through hole through which the lifting pin passes, disposed in the substrate and made of a conductor; the retainer comprises an outer retainer and an inner retainer having a common central axis; the through hole is formed on the central axis of the inner retainer to allow the lifting pin to move up and down; The inner diameter of the through hole is smaller than the diameter of the upper part of the lifting pin; the inner retainer is slidably supported on the outer retainer by an elastic member disposed between the inner and outer retainers; the substrate processing method includes the following steps: a step of moving the substrate into the interior of the processing container; a step of raising the plurality of lifting pins to protrude above the mounting surface to support the substrate; a step of lowering the lifting pins to receive them in the pin holes and placing the substrate on the mounting surface; a step of contacting the lifting pins with the inner retainer to make the lifting pins electrically connected to the substrate; and a step of processing the substrate by plasma.

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