Substrate processing apparatus and cleaning method

Abstract

To control supply and supply stop of high-frequency power in accordance with contact and separation between a placing base and a refrigerator.SOLUTION: A substrate treatment apparatus includes: a treatment vessel; a placing base configured to be rotatable while holding a substrate in the treatment vessel; a refrigerator configured to come into contact with the placing base and be separated from the placing base to cool the placing base; a mechanism for rotating the placing base and lifting up and down the refrigerator; a power supply part for supplying high-frequency power; and a power supply line penetrating through the refrigerator, including a contact part, and configured to be capable of switching supply and supply stop of the high-frequency power by connecting or disconnecting the contact part to a specific position of the placing base.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a substrate processing apparatus and a cleaning method. [Background technology]

[0002] For example, Patent Document 1 proposes a cleaning method for a mounting table in a plasma processing apparatus, which removes deposits that have accumulated on the outer periphery of the mounting table while minimizing damage to the mounting table. This cleaning method includes a separating step and a removing step. In the separating step, the mounting table and the substrate are separated from each other using an elevation mechanism. In the removing step, after the separating step, high-frequency power is supplied from a high-frequency power source to the mounting table to generate plasma and remove the deposits that have accumulated on the mounting table. In the separating step, the separation distance between the mounting table and the substrate is set so that the composite impedance formed around the outer periphery of the mounting table is lower than the composite impedance formed directly above the center of the mounting table.

[0003] For example, Patent Document 2 proposes a substrate processing apparatus in which the impedance matching state is maintained without any significant change even when the substrate holder moves. This substrate processing apparatus has a processing chamber, a substrate holder located within the processing chamber for holding a substrate, a high-frequency power supply for supplying high-frequency power to the substrate holder, a matching box located electrically between the substrate holder and the high-frequency power supply, and a movement mechanism for moving the substrate holder and the matching box together. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-86968 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-246392 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides a technique that can control the supply and stop of high-frequency power supply depending on whether the mounting table is in contact with or separated from the refrigeration device. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, a processing chamber includes: a rotatable mounting table configured to hold a substrate within the processing chamber; a refrigeration unit configured to come into contact with or separate from the mounting table and cool the mounting table; a mechanism for rotating the mounting table and raising and lowering the refrigeration unit; a power supply unit that supplies high-frequency power; and a power supply line that passes through the refrigeration unit, has a contact portion, and is configured to be able to switch between supplying and stopping the high-frequency power by connecting or disconnecting the contact portion to a specific position on the mounting table. a substrate processing apparatus, wherein while the substrate processing apparatus is idle, the mechanism brings the refrigeration device into contact with the mounting table to cool the mounting table, while the contact portion is connected to the specific position to supply the high-frequency power from the power supply line to the mounting table, thereby cleaning the inside of the processing chamber; A substrate processing apparatus is provided. [Effects of the Invention]

[0007] According to one aspect, the supply and stop of high frequency power can be controlled in response to contact or separation between the mounting table and the refrigeration device. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 10 is a cross-sectional view showing an example of the configuration of the substrate processing apparatus when rotating a mounting table according to an embodiment. [Figure 2] FIG. 10 is a cross-sectional view showing an example of the configuration of the substrate processing apparatus during cooling of the mounting table according to the embodiment. [Figure 3] 1 is a flowchart illustrating an example of a substrate processing method according to an embodiment. [Figure 4] 5A and 5B are diagrams illustrating the operation of the mounting table and the refrigeration device according to the embodiment. [Figure 5] 1 is a flowchart illustrating an example of a cleaning method according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0010] In this specification, deviations in directions such as parallel, right angles, orthogonal, horizontal, vertical, up / down, left / right, etc. are permitted to the extent that they do not impair the effects of the embodiments. The shape of the corners is not limited to right angles and may be rounded like an arch. Parallel, right angles, orthogonal, horizontal, vertical, circular, and coincident may also include approximately parallel, approximately right angles, approximately orthogonal, approximately horizontal, approximately vertical, approximately circular, and approximately coincident.

[0011] [Substrate processing equipment] An example of a substrate processing apparatus 1 according to an embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a cross-sectional view showing an example of the configuration of the substrate processing apparatus 1 according to an embodiment when a mounting table 20 is rotating. Fig. 2 is a cross-sectional view showing an example of the configuration of the substrate processing apparatus 1 according to an embodiment when the mounting table 20 is cooling.

[0012] The substrate processing apparatus 1 may be, for example, a CVD (Chemical Vapor Deposition) apparatus or an ALD (Atomic Layer Deposition) apparatus that supplies a processing gas into a processing vessel 10 and performs a desired process (e.g., a film formation process) on a substrate W. Alternatively, the substrate processing apparatus 1 may be, for example, a PVD (Physical Vapor Deposition) apparatus that supplies a processing gas into the processing vessel 10 and sputters a target provided in the processing vessel 10 to form a film on the substrate W.

[0013] A case will be described in which the substrate processing apparatus 1 is a PVD apparatus. In this case, one or more targets are provided in the ceiling of a processing vessel 10. The substrate processing apparatus 1 adheres (deposits) sputtered particles (film-forming atoms) emitted from the one or more targets to the surface of a substrate W, such as a semiconductor wafer, placed on a mounting table 20 within the processing vessel 10, thereby performing a film-forming process on the substrate W. The substrate processing apparatus 1 also has a cathode portion of a sputtering source in the ceiling of the processing vessel 10. The substrate processing apparatus 1 is, for example, a magnetron sputtering apparatus.

[0014] The substrate processing apparatus 1 includes a processing vessel 10, a mounting table 20 on which a substrate W is placed inside the processing vessel 10, a refrigeration device 30, a rotation device 40 that rotates the mounting table 20, and an elevation device 50 that raises and lowers the refrigeration device 30. The substrate processing apparatus 1 also includes a control device 70 that controls various devices such as the refrigeration device 30, the rotation device 40, and the elevation device 50.

[0015] A mounting table 20 on which a substrate W is placed is provided inside the processing vessel 10. The processing vessel 10 forms an internal space 10S above the mounting table 20. The processing vessel 10 is configured so that the internal space 10S can be depressurized to an ultra-high vacuum by operating an exhaust device (not shown) such as a vacuum pump. The processing vessel 10 is also configured so that a desired gas used for substrate processing is supplied to it via a gas supply pipe (not shown) that communicates with a gas supply unit (not shown).

[0016] The mounting table 20 holds the substrate W in the processing chamber 10 and is rotatable by the rotation device 40. The mounting table 20 includes an electrostatic chuck 21 and a base 23. The electrostatic chuck 21 is formed on the base 23. The electrostatic chuck 21 has a structure in which an insulating film such as an alumina (Al2O3) film, a metal film such as copper, and a sprayed film made of the insulating film are applied to the base 23. The metal film sandwiched between the insulating films is a chuck electrode (not shown). In other words, the upper insulating film (sprayed film) of the chuck electrode forms the mounting surface 21a of the electrostatic chuck 21. The electrostatic chuck 21 may be a Johnson-Rahbek type or a Coulomb type.

[0017] The substrate processing apparatus 1 includes a power supply unit 39. The power supply unit 39 includes a first high frequency power supply 36 that supplies high frequency power for biasing at a first frequency, a second high frequency power supply 81 that supplies high frequency power for cleaning at a second frequency, and a DC power supply 37 that supplies a direct current (DC voltage) to the chuck electrode.

[0018] The substrate processing apparatus 1 also has a slip ring 60 made of metal. The slip ring 60 is made of metal and has a rotating body 61 including a metal ring that is arranged below the rotating shaft 44 and housing 46 of the rotating device 40, and a fixed body 62 that includes a brush.

[0019] The rotating body 61 has a generally cylindrical shape that extends coaxially with the rotating shaft 44, and is fixed to the lower surface of the rotating shaft 44. The fixed body 62 has a generally cylindrical shape whose inner diameter is slightly larger than the outer diameter of the rotating body 61, and is fixed to the lower surface of the housing 46.

[0020] The slip ring 60 is electrically connected to the DC power supply 37, and supplies power from the DC power supply 37 to the wiring 63 via the brushes of the fixed body 62 and the metal ring of the rotating body 61. The DC power supply 37 applies a direct current voltage to the chuck electrode via the slip ring 60 and the wiring 63. With this configuration, the power supply unit 39 can apply a potential from the DC power supply 37 to the chuck electrode without causing twisting or the like in the wiring 63. Note that the structure of the slip ring 60 may be a structure other than a brush structure, and may be, for example, a contactless power supply structure or a structure including mercury-free or conductive liquid.

[0021] The power supply unit 39 includes a splitter 38. The splitter 38 separates the DC voltage applied to the chuck electrode from the DC power supply 37, the bias RF power supplied to the electrostatic chuck 21 (substrate W) from the first RF power supply 36, and the cleaning RF power supplied to the mounting table 20 from the second RF power supply 81. Because the bias RF power is AC, the bias RF current is not insulated by the insulating film covering the chuck electrode and also flows to the base 23. The refrigeration device 30 is made of low-resistivity copper and is connected to the ground. Therefore, if the base 23 were made of low-resistivity copper, the bias RF power supplied to the electrostatic chuck 21 (substrate W) would flow to the refrigeration device 30, which is connected to the ground, rather than flowing to the wall of the processing chamber 10 via the ionized particles. This makes it difficult for the bias RF power to be applied to the ionized particles. Therefore, the base 23 is made of quartz. This prevents the bias high-frequency current from flowing toward the refrigeration device 30, and allows the bias high-frequency power to be applied to the ionized particles. By using quartz for the base 23 in this manner, a potential difference can be generated by supplying bias high-frequency power to the electrostatic chuck 21 (substrate W), and the ionized sputtered particles can be attracted to the substrate W.

[0022] The DC voltage separated by the splitter 38 is applied to the electrostatic chuck 21 (chuck electrode) via the slip ring 60 and wiring 63. The bias high-frequency power separated by the splitter 38 is supplied to the electrostatic chuck 21 (substrate W) via the slip ring 60 and wiring 63 and superimposed on the DC voltage. The cleaning high-frequency power separated by the splitter 38 is supplied to the electrode unit 22a located within the mounting table 20 below the chuck electrode via a power supply line 82 that passes through the refrigeration device 30, which is a supply path separate from the slip ring 60 and wiring 63. The electrode unit 22a has a disk shape with a diameter substantially equal to or similar to that of the mounting table 20. Note that the substrate processing apparatus 1 according to this embodiment requires the installation of a dedicated metal plate (not shown) within the quartz base 23 for supplying the bias high-frequency power. The insertion of the metal plate does not reduce the cooling efficiency of the mounting table 20, ensuring cooling performance equivalent to that of conventional systems.

[0023] The frequency of the high frequency power for bias (first frequency) is, for example, 400 kHz. The frequency of the high frequency power for cleaning (second frequency) is, for example, 13.56 MHz. However, the first frequency is not limited to 400 kHz. Furthermore, the second frequency is not limited to 13.56 MHz. The second frequency may be different from the first frequency, or may be higher than the first frequency. The first high frequency power supply 36 is connected to a matcher 35 for efficiently applying high frequency power for bias to the mounting table 20, and is connected to a splitter 38 via the matcher 35. The second high frequency power supply 81 is connected to a matcher 80 for efficiently applying high frequency power for cleaning to the mounting table 20, and is connected to the splitter 38 via the matcher 80.

[0024] A refrigeration device 30 is provided below the mounting table 20. The refrigeration device 30 is configured to be in contact with or spaced from the mounting table 20 and to cool the mounting table 20. The refrigeration device 30 includes a refrigerator 31 and a refrigeration heat transfer medium 32. The refrigeration heat transfer medium 32 is also called a cold drink. The refrigerator 31 holds the refrigeration heat transfer medium 32 and cools the upper surface of the refrigeration heat transfer medium 32 to an extremely low temperature. From the viewpoint of cooling capacity, the refrigerator 31 preferably uses a Gifford-McMahon (GM) cycle. The refrigeration heat transfer medium 32 is fixed on the refrigerator 31, and its upper portion is housed inside the processing vessel 10. The refrigeration heat transfer medium 32 is made of a material with high thermal conductivity (e.g., Cu) and has an approximately cylindrical outer shape. The refrigeration heat transfer medium 32 is arranged so that its center coincides with the central axis CL of the mounting table 20.

[0025] The refrigeration device 30 has a contact surface 30a that comes into contact with or is separated from the contact surface 20a of the mounting table 20, and is configured to cool the mounting table 20. When the substrate processing apparatus 1 is idle, the lifting device 50 raises the refrigeration device 30 to bring the contact surface 30a of the refrigeration device 30 into contact with the contact surface 20a of the mounting table 20, thereby causing the refrigeration device 30 to cool the mounting table 20 to an extremely low temperature. When the substrate processing apparatus 1 is in a process (processing of a substrate W), the lifting device 50 lowers the refrigeration device 30 to separate the contact surface 30a of the refrigeration device 30 from the contact surface 20a of the mounting table 20, and then the rotation device 40 rotates the mounting table 20, and a film formation process is performed on the substrate W on the mounting table 20.

[0026] For example, the refrigeration device 30 may come into contact with the contact surface 20a of the mounting table 20 and cool the electrostatic chuck 21 so that the temperature of the substrate W attracted and held on the mounting surface 21a becomes an extremely low temperature of 150 K (Kelvin) or less. Furthermore, the refrigeration device 30 may come into contact with the contact surface 20a of the mounting table 20 and cool the electrostatic chuck 21 so that the temperature of the substrate W becomes an extremely low temperature of 210 K (Kelvin) or less. In the refrigeration device 30, at least the refrigeration heat medium 32 is made of a metal such as copper and is connected to a ground potential. In this embodiment, the parts of the refrigeration device 30 other than the refrigerator 31 are made of copper.

[0027] The mounting table 20 is rotatably supported by a rotation device 40. The rotation device 40 includes a rotation drive device 41, a fixed shaft 45, a rotating shaft 44, a housing 46, magnetic fluid seals 47 and 48, and a stand 49.

[0028] The rotary drive device 41 is a direct drive motor having a rotor 42 and a stator 43. The rotor 42 has a generally cylindrical shape extending coaxially with the rotary shaft 44 and is fixed to the rotary shaft 44. The stator 43 has a generally cylindrical shape with an inner diameter larger than the outer diameter of the rotor 42. The rotary drive device 41 may be in a form other than a direct drive motor, and may be in a form including a servo motor and a transmission belt, for example.

[0029] The rotating shaft 44 has a generally cylindrical shape that extends coaxially with the central axis CL of the mounting table 20. A fixed shaft 45 is provided radially inside the rotating shaft 44. The fixed shaft 45 has a generally cylindrical shape that extends coaxially with the central axis CL of the mounting table 20. A housing 46 is provided radially outside the rotating shaft 44. The housing 46 has a generally cylindrical shape that extends coaxially with the central axis CL of the mounting table 20, and is fixed to the processing vessel 10.

[0030] A magnetic fluid seal 47 is provided between the outer circumferential surface of the fixed shaft 45 and the inner circumferential circle of the rotating shaft 44. The magnetic fluid seal 47 rotatably supports the rotating shaft 44 relative to the fixed shaft 45 and seals the gap between the outer circumferential surface of the fixed shaft 45 and the inner circumferential circle of the rotating shaft 44, thereby separating the depressurizable internal space 10S of the treatment vessel 10 from the external space of the treatment vessel 10. A magnetic fluid seal 48 is provided between the inner circumferential surface of the housing 46 and the outer circumferential circle of the rotating shaft 44. The magnetic fluid seal 48 rotatably supports the rotating shaft 44 relative to the housing 46 and seals the gap between the inner circumferential surface of the housing 46 and the outer circumferential circle of the rotating shaft 44, thereby separating the depressurizable internal space 10S of the treatment vessel 10 from the external space of the treatment vessel 10. As a result, the rotating shaft 44 is rotatably supported by the fixed shaft 45 and the housing 46. A refrigeration heat transfer medium 32 is inserted radially inside the fixed shaft 45.

[0031] The stand 49 is provided vertically between the rotating shaft 44 and the mounting table 20, and is configured to transmit the rotation of the rotating shaft 44 to the mounting table 20. With the above configuration, when the rotor 42 of the rotation drive device 41 rotates, the rotating shaft 44, the stand 49, and the mounting table 20 rotate in the X1 direction (FIG. 1) relative to the refrigeration heat transfer medium 32.

[0032] The refrigeration device 30 is supported so as to be movable up and down by an elevator device 50. The rotation device 40 and the elevator device 50 are an example of a mechanism that rotates the mounting table 20 and moves the refrigeration device 30 up and down.

[0033] The lifting device 50 includes an air cylinder 51 , a link mechanism 52 , a refrigeration device support portion 53 , a linear guide 54 , a fixing portion 55 , and a bellows 56 .

[0034] The air cylinder 51 is a mechanical device whose rod moves linearly due to air pressure. The link mechanism 52 converts the linear movement of the rod of the air cylinder 51 into the lifting and lowering movement of the refrigeration device support part 53. The link mechanism 52 has a lever structure with one end connected to the air cylinder 51 and the other end connected to the refrigeration device support part 53. This allows a large pressing force to be generated with a small thrust of the air cylinder 51. The refrigeration device support part 53 supports the refrigeration device 30 (refrigerator 31, refrigeration heat medium 32). The movement of the refrigeration device support part 53 is guided in the lifting and lowering direction by a linear guide 54.

[0035] The fixed part 55 is fixed to the lower surface of the fixed shaft 45. A substantially cylindrical bellows 56 surrounding the refrigerator 31 is provided between the lower surface of the fixed part 55 and the upper surface of the refrigeration device support part 53. The bellows 56 is a metal bellows structure that is expandable and contractible in the vertical direction. As a result, the fixed part 55, the bellows 56, and the refrigeration device support part 53 seal the gap between the inner circumferential surface of the fixed shaft 45 and the outer circumferential circle of the refrigeration heat transfer medium 32, separating the internal space 10S of the treatment vessel 10, which can be depressurized, from the external space of the treatment vessel 10. The lower surface of the refrigeration device support part 53 is adjacent to the external space of the treatment vessel 10, and the area of ​​the upper surface of the refrigeration device support part 53 surrounded by the bellows 56 is adjacent to the internal space 10S of the treatment vessel 10.

[0036] A loading / unloading port 111 and a gate valve 112 are provided on the side of the processing vessel 10. The gate valve 112 opens and closes the loading / unloading port 111. When the gate valve 112 opens, a transfer device (not shown) loads a substrate W into the processing vessel 10 through the loading / unloading port 111 and places the substrate W on the electrostatic chuck 21. When the transfer device retreats from the loading / unloading port 111, the control device 70 closes the gate valve 112.

[0037] When the substrate processing apparatus 1 is a PVD apparatus, a cathode (not shown) is provided on the ceiling of the processing chamber 10, facing the mounting table 20, and configured to sputter one or more targets. The power source connected to the cathode may be at least one of a DC (direct current) power source and an RF (radio frequency) power source. At least one of a DC (direct current) power source and an RF (radio frequency) power source (not shown) may apply at least one of a DC voltage and a radio frequency power to the cathode.

[0038] The control device 70 is, for example, a computer, and includes a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), an auxiliary storage device, etc. The CPU operates based on a program stored in the ROM or the auxiliary storage device, and controls the operation of the substrate processing apparatus 1. The control device 70 can control the substrate processing apparatus 1 via a communication means such as a wired or wireless communication means.

[0039] [Mechanism for switching on and off the supply of high-frequency power] The substrate processing apparatus 1 according to this embodiment includes a power supply line 82 configured to be able to switch between supplying and stopping the supply of high frequency power from a second high frequency power supply 81. In this embodiment, the high frequency power from the second high frequency power supply 81 is high frequency power for cleaning.

[0040] The power supply line 82 passes through the refrigeration device 30 and has a contact portion 82a at its tip. The contact portion 82a protrudes from the upper surface (contact surface 30a) of the refrigeration device 30. The power supply line 82 can switch between supplying and stopping the high-frequency power for cleaning to the mounting table 20 by connecting or disconnecting the contact portion 82a to or from a specific position on the mounting table 20.

[0041] The specific position of the mounting table 20 is a position facing the contact portion 82a of the mounting table 20, and the mounting table 20 has a recess 21c at the specific position. The recess 21c is formed in the center of the disk-shaped electrode portion 22a, below the support portion 21b that supports the electrode portion 22a. The recess 21c is recessed inward (toward the electrode portion 22a) from the lower surface of the support portion 21b, which is flush with the contacted surface 20a of the mounting table 20. The recess 21c is connected to the electrode portion 22a via the support portion 21b. The electrode portion 22a and the support portion 21b are formed of a conductive material, for example, copper, aluminum, or an alloy of copper and aluminum.

[0042] The contact portion 82a is connected to or disconnected from the recess 21c by the lifting device 50 raising or lowering the refrigeration device 30. For example, while the substrate processing apparatus 1 is idle, the lifting device 50 raises the refrigeration device 30 and brings the refrigeration device 30 into contact with the mounting table 20, thereby cooling the mounting table 20. At this time, the contact surface 30a of the refrigeration device 30 comes into contact with the contacted surface 20a of the mounting table 20, and the contact portion 82a is automatically inserted into and contacts the recess 21c, and the power supply line 82 is connected to the electrode portion 22a via the contact portion 82a. As a result, while the substrate processing apparatus 1 is idle, the mounting table 20 is cooled, and the contact portion 82a is connected to a specific position (recess 21c), and high-frequency power for cleaning is supplied from the power supply line 82 to the electrode portion 22a, thereby cleaning the inside of the processing chamber 10.

[0043] In this embodiment, during a process (film formation on the substrate W) in the substrate processing apparatus 1, the first high frequency power supply 36 supplies bias high frequency power to the electrostatic chuck 21. This allows the ionized sputtered particles to be efficiently attracted to the mounting table 20, thereby increasing the efficiency of film formation on the substrate W by the sputtered particles.

[0044] Furthermore, while the substrate processing apparatus 1 is performing a process, the lifting device 50 lowers the freezing device 30, and after the freezing device 30 is moved away from the mounting table 20, the rotation device 40 rotates the mounting table 20 while forming a film on the substrate on the mounting table 20. Furthermore, while the substrate processing apparatus 1 is performing a process, the contact portion 82a is moved away from the specific position (recess 21c) to cut off electrical continuity and stop the supply of high-frequency power for cleaning to the electrode portion 22a.

[0045] As the number of continuously processed substrates W increases, impurities on the substrates W adhere to the mounting surface 21a of the electrostatic chuck 21, reducing the electrostatic chuck 21's clamping force. This can lead to clamping force errors and reduced cooling efficiency due to increased heat transfer gas leakage. Conventionally, the surface of the electrostatic chuck 21 has been cleaned using plasma by applying high-frequency power from the first high-frequency power supply 36 to the mounting table 20 without a substrate W placed on it. However, this can result in uneven plasma formation on the mounting table 20, resulting in inconsistent cleaning of the surface of the mounting table 20. If the entire mounting table 20 is not cleaned uniformly, there is a risk of uneven temperature distribution during the process. Furthermore, conventionally, restoring the electrostatic chuck 21's clamping force requires replacing the electrostatic chuck 21 (mounting table 20) or installing a dedicated cleaning tool. This increases downtime for maintenance, reducing production efficiency, and requires maintaining an inventory of dedicated cleaning tools or replacement electrostatic chucks 21, resulting in increased running costs. For these reasons, there has been a demand for efficient cleaning that can be performed in situ without opening the processing vessel 10 to the atmosphere when replacing the electrostatic chuck 21 or the like, and without breaking the vacuum.

[0046] Therefore, in this embodiment, after processing a set number of substrates W (e.g., 100 substrates) without causing downtime, cleaning is performed during idle time, i.e., between processes. At this time, plasma is generated from the cleaning gas supplied into the processing vessel 10 by the high-frequency power for cleaning supplied from the second high-frequency power supply 81 to the electrode unit 22a via the power supply line 82, and the inside of the processing vessel 10 is cleaned by the plasma. By supplying the high-frequency power for cleaning to the disk-shaped electrode unit 22a in the mounting table 20, the entire mounting table 20 is targeted for sputtering, and ions in the plasma generated from the cleaning gas are sputtered uniformly over the entire mounting table 20. This allows the entire mounting table 20 to be cleaned uniformly without uneven cleaning.

[0047] Furthermore, the cleaning method according to this embodiment can be performed while the mounting table 20 is cooled before, between, or after a process while the substrate processing apparatus 1 is idling. Therefore, efficient cleaning can be performed in the substrate processing apparatus 1 according to this embodiment, which performs film formation in an extremely low temperature environment. Note that even when the substrate processing apparatus 1 is idling, the cleaning process is not performed while the number of processed substrates W has not reached the set number.

[0048] In this embodiment, during processing, the substrate processing apparatus 1 lowers the lifting device 50 to separate the refrigeration device 30 from the mounting table 20, and then the rotation device 40 rotates the mounting table 20 while forming a film on the substrate W on the mounting table 20. At this time, as the refrigeration device 30 moves away from the mounting table 20, the contact portion 82a automatically moves away from the specific position (recess 21c) and is cut off. This automatically stops the supply of high-frequency power for cleaning to the electrode portion 22a.

[0049] The structure surrounding the power supply line 82 will be further described with reference to FIG. 1. The power supply line 82 is inserted into a through hole provided inside the refrigeration device 30. The through hole is arranged so that its center coincides with the central axis CL, but this is not limited to this. The power supply line 82 is formed of a conductive material, such as copper. The power supply line 82 is configured so as not to be electrically connected to the refrigeration device 30. As an example, as shown in FIG. 1, a protective part 83 made of a cylindrical insulating material is provided between the inner wall of the through hole of the refrigeration device 30 and the power supply line 82. The power supply line 82 is arranged inside the protective part 83.

[0050] A cavity may be formed between the power supply line 82 and the protective portion 83. The protective portion 83 and the cavity of the insulating member provide thermal and electrical insulation between the power supply line 82 and the refrigeration device 30. The power supply line 82 is fixed at one or more positions within the refrigeration device 30 by a support portion 84 of the insulating member. The insulating members of the protective portion 83 and the support portion 84 may be formed of ceramic with low thermal conductivity. For example, the power supply line 82 may be fixed at multiple positions by the support portion 84 of the insulating member, such as at or near the tip of the power supply line 82, at or near the end of the power supply line 82, or in the center of the power supply line 82. This allows the power supply line 82 to be thermally and electrically insulated from the refrigeration device 30 (the refrigeration heat medium 32) by the insulating member, and allows the support portion 84 to fix the power supply line 82 in the space of the through-hole. This allows stable supply of high-frequency power for cleaning from the power supply line 82 to the electrode portion 22a via the contact portion 82a.

[0051] Instead of providing protective portion 83 made of a cylindrical insulating material between the inner wall of the through-hole of refrigeration device 30 and power supply line 82, an insulating material such as ceramics may be filled between the inner wall of the through-hole of refrigeration device 30 and power supply line 82. This also ensures insulation between refrigeration device 30 and power supply line 82.

[0052] In the substrate processing apparatus 1 according to this embodiment, the frequency of the high frequency power for cleaning (second frequency) is set to a frequency band of approximately 13 MHz or the like for generating capacitively coupled plasma. On the other hand, the frequency of the high frequency power for biasing (first frequency) can be set to various frequencies depending on the type of gas used in the process (film formation process for the substrate W), etc.

[0053] The bias high-frequency power is supplied to the surface of the electrostatic chuck 21 of the mounting table 20 in order to attract ions in the plasma toward the substrate W. On the other hand, the cleaning high-frequency power is preferably supplied not only to the surface of the electrostatic chuck 21 but also to the electrode portion 22 a of the mounting table 20 in order to clean the entire mounting table 20.

[0054] For the above reasons, it is preferable to provide the first high frequency power supply 36, which supplies high frequency power for biasing, and the second high frequency power supply 81, which supplies high frequency power of the second frequency for cleaning, separately. This allows the first high frequency power supply 36 to supply high frequency power of the first frequency in a frequency band suited to each process, thereby increasing the degree of freedom in the film formation process that can be performed in the substrate processing apparatus 1. Furthermore, by supplying high frequency power of the second frequency different from the first frequency suited to cleaning from the second high frequency power supply 81, it is possible to clean not only the surface of the electrostatic chuck 21 but also the entire mounting table 20.

[0055] [Substrate processing method] A substrate processing method ST1 according to one embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a flowchart showing an example of the substrate processing method ST1 according to one embodiment. FIG. 4 is a diagram for explaining the operation of the mounting table 20 (electrostatic chuck 21) and the refrigeration device 30 according to one embodiment. The substrate processing method ST1 is controlled by the control device 70 and executed in the substrate processing apparatus 1. In the substrate processing method ST1, a desired film is formed on a substrate W.

[0056] When the substrate processing method ST1 is started, in step S1, the controller 70 controls the gas exhaust unit to evacuate (reducing) the inside of the processing chamber 10 to a predetermined vacuum level.

[0057] Next, in step S2, the control device 70 raises the lifting device 50 to bring the mounting table 20 (electrostatic chuck 21) into contact with the refrigeration device 30, and cools the mounting table 20 to an extremely low temperature (for example, 150 K or lower).

[0058] Next, the process proceeds to step S3, where the substrate W is loaded into the processing vessel 10 and placed on the mounting table 20 (see FIG. 4(a)). Specifically, the controller 70 opens the gate valve 112, and causes a transfer device (not shown) to load the substrate W into the processing vessel 10 through the load / unload port 111 and place it on the mounting table 20. When the transfer device retreats from the load / unload port 111, the controller 70 closes the gate valve 112.

[0059] Next, in step S4, the control device 70 determines whether to start the process. If the control device 70 determines not to start the process, the process returns to step S2, and the cooling of the mounting table 20 continues.

[0060] On the other hand, if the control device 70 determines in step S4 to start the process, then in step S5, the control device 70 applies a DC voltage from the DC power supply 37 to the chucking electrode of the electrostatic chuck 21, thereby electrostatically attracting the substrate W to the electrostatic chuck 21 (see FIG. 4(b)). The control device 70 also supplies a high-frequency bias power from the first high-frequency power supply 36 to the mounting table 20 (electrostatic chuck 21). Since the substrate W is electrostatically attracted to the electrostatic chuck 21, the cooling efficiency can be improved. Furthermore, a heat transfer gas flow path (not shown) may be provided in the electrostatic chuck 21 to supply a heat transfer gas between the substrate W and the electrostatic chuck 21. This can improve the heat transfer efficiency.

[0061] Next, in step S6, the control device 70 lowers the lifting device 50 to separate the mounting table 20 from the refrigeration device 30 (see FIG. 4(c)). Next, in step S7, the control device 70 controls the rotation device 40 to rotate the mounting table 20 holding the substrate W (see FIG. 4(c)). This improves the distribution of the film formed on the substrate W. The control device 70 also supplies a process gas (film formation gas) from the gas supply unit. Ions in the plasma generated from the process gas collide with a target (not shown), and sputtered particles are emitted from the target into the internal space 10S. The emitted sputtered particles are ionized with high efficiency, and the ions can be attracted by the high-frequency bias power supplied to the mounting table 20 (electrostatic chuck 21). This allows the sputtered particles to efficiently adhere (deposit) on the substrate W, thereby forming a film such as a Cu film.

[0062] When the process is completed, in step S8, the control device 70 controls the rotation device 40 to stop the rotation of the mounting table 20 and stops the supply of process gas from the gas supply unit. The control device 70 also stops the application of DC voltage and the supply of high-frequency bias power to the electrostatic chuck 21, thereby releasing the electrostatic attraction of the substrate W to the electrostatic chuck 21 (see FIG. 4(d)). The control device 70 may also apply a DC voltage of a polarity opposite to that during the process to the electrostatic chuck 21 to release the electrostatic attraction of the substrate W to the electrostatic chuck 21.

[0063] Next, in step S9, the control device 70 opens the gate valve 112, and causes a transfer device (not shown) to unload the substrate W from the processing chamber 10 through the loading / unloading port 111 (see FIGS. 4(d) and 4(e)). When the transfer device retreats from the loading / unloading port 111, the control device 70 closes the gate valve 112.

[0064] Next, in step S10, the control device 70 determines whether there is a next substrate W on which a film is to be formed. If the control device 70 determines that there is a next substrate W, it returns to step S2 and performs the processes from step S2 onwards on the next substrate W (see FIG. 4(a)). If it is determined in step S10 that there is no next substrate W, this process ends.

[0065] When the substrate W is cooled, the substrate W is cooled to an extremely low temperature of about 72 K (Kelvin), i.e., about −200° C. However, the extremely low temperature is not limited to −200° C., and may be −233° C. to −123° C. For example, when a film such as a Cu film is formed on the substrate W in a state where the substrate W is cooled to an extremely low temperature, aggregation of Cu particles and the like can be reduced, and the sheet resistance and surface roughness of the film such as a Cu film can be reduced compared to when the film is formed at room temperature, and a high-quality film such as a Cu film can be formed.

[0066] In addition, the cooling efficiency can be improved because the substrate W is electrostatically attracted to the electrostatic chuck 21. Furthermore, the high frequency bias power can attract ions to the substrate W during film formation on the substrate W, thereby improving film formation efficiency.

[0067] [Cleaning method] A cleaning method ST2 according to one embodiment will be described with reference to Fig. 5. Fig. 5 is a flowchart showing an example of the cleaning method ST2 according to one embodiment. The cleaning method ST2 is controlled by the control device 70 and executed in the substrate processing apparatus 1.

[0068] When this process is started, in step S11, the control device 70 determines whether the substrate processing apparatus 1 is idle. If the control device 70 determines that the substrate processing apparatus 1 is not idle, this process ends.

[0069] On the other hand, if the control device 70 determines in step S11 that the substrate processing apparatus 1 is idle, it determines in step S12 whether a set number of substrates W have been processed since the previous cleaning. The set number determines the cleaning cycle and is set in advance to a number corresponding to the period during which the mounting table 20 and the like are to be cleaned. One example of the set number is 100, but it is not limited to this. The set number is set to a number less than the number of substrates W that can be continuously processed at which a phenomenon occurs in which impurities on the substrates W adhere to the mounting surface 21 a of the electrostatic chuck 21, thereby reducing the adsorptive force of the electrostatic chuck 21.

[0070] If the control device 70 determines that the set number of substrates W have not been processed since the previous cleaning, it terminates this process. On the other hand, if the control device 70 determines in step S12 that the set number of substrates W have been processed since the previous cleaning, it supplies high-frequency power for cleaning from the second high-frequency power supply 81 in step S13. During idle, the mounting table 20 and the refrigeration device 30 come into contact with each other in step S2 of Fig. 3, and the contact portion 82a automatically connects to the recess 21c (see Figs. 4(a) and (b)).

[0071] As a result, high-frequency power for cleaning is supplied from the power supply line 82 through the contact portion 82a to the electrode portion 22a of the mounting table 20. Plasma is generated from the cleaning gas supplied into the processing chamber 10, and the entire mounting table 20 is cleaned by the generated plasma.

[0072] Next, in step S14, the control device 70 determines whether the process should be started. If the control device 70 determines not to start the process, the process returns to step S13 and continues cleaning.

[0073] On the other hand, in step S14, when the control device 70 determines to start the process, the mounting table 20 and the refrigeration device 30 are separated (steps S4 to S6 in FIG. 3). This automatically disconnects the contact portion 82a from the recessed portion 21c of the mounting table 20 (see FIG. 4(c)). As a result, in step S15, the control device 70 stops the supply of high-frequency power for cleaning, completes the cleaning, and ends this process.

[0074] As described above, according to the substrate processing apparatus 1 and cleaning method of this embodiment, the supply and stop of high-frequency power can be automatically controlled in response to contact or separation between the mounting table 20 and the refrigeration device 30.

[0075] The substrate processing apparatus 1 and cleaning method according to the presently disclosed embodiments should be considered to be illustrative in all respects and not restrictive. The embodiments can be modified and improved in various ways without departing from the spirit and scope of the appended claims. The features described in the above embodiments can be configured differently within a consistent range, and can be combined within a consistent range. [Explanation of symbols]

[0076] 1. Substrate processing equipment 10 Processing container 20 Mounting table 21 Electrostatic chuck 22a Electrode section 23 Foundation 30 Refrigeration equipment 31 Refrigeration Machine 32 Refrigeration heat transfer medium 36 1st high frequency power supply 37 DC power supply 38 Splitter 39 Power supply section 40 Rotating Device 50 Lifting device 70 Control device 81 2nd high frequency power supply 82 Power supply line 83 Protection Department 84 Fixed part 82a Contact part W substrate

Claims

1. A processing vessel; a mounting table configured to hold a substrate and be rotatable within the processing chamber; a refrigeration device that is in contact with or spaced apart from the mounting table and configured to cool the mounting table; a mechanism for rotating the mounting table and elevating the refrigeration device; a power supply unit that supplies high frequency power; a power supply line that passes through the refrigeration device, has a contact portion, and is configured to be able to switch between supplying and stopping the high-frequency power by connecting or disconnecting the contact portion to a specific position on the mounting table, while the substrate processing apparatus is idle, the mechanism brings the refrigeration device into contact with the mounting table to cool the mounting table, while the contact portion is connected to the specific position to supply the high-frequency power from the power supply line to the mounting table, thereby cleaning the inside of the processing vessel. Substrate processing equipment.

2. a plasma is generated from a cleaning gas supplied into the processing vessel by the high frequency power supplied to the mounting table, and the inside of the processing vessel is cleaned by the plasma; The substrate processing apparatus according to claim 1 .

3. A processing vessel; a mounting table configured to hold a substrate and be rotatable within the processing chamber; a refrigeration device that is in contact with or spaced apart from the mounting table and configured to cool the mounting table; a mechanism for rotating the mounting table and elevating the refrigeration device; a power supply unit that supplies high frequency power; a power supply line that passes through the refrigeration device, has a contact portion, and is configured to be able to switch between supplying and stopping the high-frequency power by connecting or disconnecting the contact portion to a specific position on the mounting table, During a process, the substrate processing apparatus separates the refrigeration device from the mounting table by the mechanism, and then processes the substrate on the mounting table while rotating the mounting table, and disconnects the contact portion from the specific position to stop the supply of the high-frequency power to the mounting table. Substrate processing equipment.

4. the specific position is a position on the mounting table facing the contact portion, the mounting table has a recess at the specific position, The contact portion protrudes from an upper surface of the refrigeration device, The contact portion is connected to or disconnected from the recess by raising or lowering the refrigeration device using the mechanism. The substrate processing apparatus according to claim 1 .

5. the mounting table has an electrode portion connected to the recess, The high-frequency power is supplied to the electrode portion from the power supply line by connecting the contact portion to the recess. The substrate processing apparatus according to claim 4 .

6. the contact portion and the power supply line are conductive members, The power supply line is covered with a protective portion made of an insulating material inside the refrigeration device. The substrate processing apparatus according to claim 1 .

7. the power supply line is disposed inside the cylindrical protective part and fixed by a fixing part of an insulating member at one or more positions in the refrigeration apparatus. The substrate processing apparatus according to claim 6 .

8. A processing vessel; a mounting table configured to hold a substrate and be rotatable within the processing chamber; a refrigeration device that is in contact with or spaced apart from the mounting table and configured to cool the mounting table; a mechanism for rotating the mounting table and elevating the refrigeration device; a power supply unit that supplies high frequency power; a power supply line that passes through the refrigeration device, has a contact portion, and is configured to be able to switch between supplying and stopping the high-frequency power by connecting or disconnecting the contact portion to a specific position on the mounting table; the power supply unit includes a first high frequency power supply that supplies high frequency power for biasing at a first frequency, and a second high frequency power supply that supplies high frequency power for cleaning at a second frequency; the mounting table is connected to the second high frequency power supply via the power supply line, the mounting table is connected to the first high frequency power supply via a wiring separate from the power supply line; Substrate processing equipment.

9. the second frequency is different from the first frequency; The substrate processing apparatus according to claim 8 .

10. A processing vessel; a mounting table configured to hold a substrate and be rotatable within the processing chamber; a refrigeration device that is in contact with or spaced apart from the mounting table and configured to cool the mounting table; a mechanism for rotating the mounting table and elevating the refrigeration device; a power supply unit that supplies high frequency power; a power supply line that passes through the refrigeration device, has a contact portion, and is configured to be able to switch between supplying and stopping the high-frequency power by connecting or disconnecting the contact portion to a specific position on the mounting table; a controller; and a method for cleaning a substrate processing apparatus, the method comprising: The control device When the substrate processing apparatus is idle, the mechanism brings the refrigeration device into contact with the mounting table to cool the mounting table, while connecting the contact portion to the specific position to supply the high-frequency power from the power supply line to the mounting table, thereby cleaning the inside of the processing vessel. Cleaning method:

11. A processing vessel; a mounting table configured to hold a substrate and be rotatable within the processing chamber; a refrigeration device that is in contact with or spaced apart from the mounting table and configured to cool the mounting table; a mechanism for rotating the mounting table and elevating the refrigeration device; a power supply unit that supplies high frequency power; a power supply line that passes through the refrigeration device, has a contact portion, and is configured to be able to switch between supplying and stopping the high-frequency power by connecting or disconnecting the contact portion to a specific position on the mounting table; a controller; and a method for cleaning a substrate processing apparatus, the method comprising: The control device When the substrate processing apparatus is in the process, the mechanism separates the refrigeration device from the stage, thereby rotating the stage and processing the substrate on the stage, and disconnects the contact portion from the specific position to stop the supply of the high-frequency power to the stage. Cleaning method:

Images