Plasma processing apparatus and processing method

Abstract

This plasma processing apparatus includes: a processing container configured to be capable of decompression; a support part provided in the processing container and configured to support a workpiece; a heat-transfer-layer-forming part configured to form a deformable heat transfer layer for the workpiece, the heat transfer layer made from at least one of a liquid layer and a solid layer, on a placement surface of the support part on which the workpiece is placed; an exhaust line configured to perform exhaust from a processing space in the processing container; and a bypass line for bypassing the exhaust line. The bypass line is provided with a trap configured to collect the gaseous heat transfer layer included in the exhaust from the processing space.

Description

Plasma processing apparatus and processing method

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

[0002] Patent document 1 discloses a substrate processing apparatus that includes a mounting table having a mounting surface on which a substrate is placed and a gas supply pipe for supplying a heat transfer gas to the gap between the substrate and the mounting surface.

[0003] Japanese Patent Application Laid-Open No. 2020-120081

[0004] The techniques of the present disclosure efficiently regulate the temperature of a workpiece during plasma processing.

[0005] One aspect of the present disclosure is a plasma processing apparatus comprising: a processing vessel configured to be depressurized; a support portion provided within the processing vessel for supporting a workpiece; a heat transfer layer forming portion that forms a deformable heat transfer layer for the workpiece, the heat transfer layer being composed of at least one of a liquid layer and a solid layer, on a mounting surface of the support portion on which the workpiece is placed; an exhaust line that exhausts air from a processing space within the processing vessel; and a bypass line that bypasses the exhaust line, the bypass line having a trap interposed therein for recovering gaseous heat transfer layer contained in the exhaust from the processing space.

[0006] According to the present disclosure, the temperature of a workpiece can be efficiently adjusted during plasma processing.

[0007] 1 is a longitudinal sectional view showing an outline of the configuration of a plasma processing apparatus according to a first embodiment; FIG. 2 is a flowchart for explaining an example of wafer processing performed using the plasma processing apparatus of FIG. 1; FIG. 3 is a view showing a state of the plasma processing apparatus during wafer processing performed using the plasma processing apparatus of FIG. 1; FIG. 4 is a view showing a state of the plasma processing apparatus during wafer processing performed using the plasma processing apparatus of FIG. 1; FIG. 5 is a view showing a state of the plasma processing apparatus during wafer processing performed using the plasma processing apparatus of FIG. 1; FIG. 6 is a view showing a state of the plasma processing apparatus during wafer processing performed using the plasma processing apparatus of FIG. 1; FIG. 7 is a view showing a vapor pressure curve of a constituent material of a heat transfer layer; FIG. 8 is a view showing a state of the plasma processing apparatus during wafer processing performed using the plasma processing apparatus of FIG. 1; FIG. 9 is a view showing a state of the plasma processing apparatus during wafer processing performed using the plasma processing apparatus of FIG. 1; FIG. 10 is a view showing a state of the plasma processing apparatus during wafer processing performed using the plasma processing apparatus of FIG. 1; FIG. 1 is a plan view schematically showing a modified example of an electrode of an electrostatic chuck. FIG. 2 is a cross-sectional view schematically showing a modified example of an electrode of an electrostatic chuck. FIG. 3 is a cross-sectional view schematically showing a modified example of an electrode of an electrostatic chuck. FIG. 4 is a cross-sectional view schematically showing a modified example of an electrode of an electrostatic chuck. FIG. 5 is a plan view schematically showing a modified example of an electrode of an electrostatic chuck. FIG. 6 is a diagram showing an example of a heat transfer layer on a wafer mounting surface. FIG. 7 is a diagram showing an example in which the central part of an electrostatic chuck is formed to have a diameter larger than the diameter of the wafer. FIG. 8 is a diagram showing another example of a wafer mounting form on a wafer mounting surface.

[0008] In the manufacturing process of semiconductor devices, etc., plasma processing such as etching and film formation is performed on semiconductor wafers (hereinafter referred to as "wafers") as workpieces using plasma. The plasma processing is performed with the substrate supported on a substrate support table inside a reduced-pressure processing chamber.

[0009] Since the results of plasma processing depend on the temperature of the substrate, the temperature of the substrate support table is adjusted during plasma processing, and the temperature of the substrate is adjusted via the substrate support table. Conventionally, a heat transfer gas such as He gas is supplied between the substrate support table and the substrate so that the temperature of the substrate can be efficiently adjusted via the substrate support table.

[0010] However, when the heat input from the plasma to the substrate during plasma processing is large, the substrate temperature may not be sufficiently adjusted even using the heat transfer gas as described above. Also, the temperature of an object other than the substrate may be adjusted via the substrate support table.

[0011] Therefore, the technology disclosed herein efficiently adjusts the temperature of a workpiece such as a substrate via a support table during plasma processing.

[0012] Hereinafter, a plasma processing apparatus and a processing method according to the present embodiment will be described with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0013] (First Embodiment) <Plasma Processing Apparatus 1> Fig. 1 is a longitudinal sectional view showing an outline of the configuration of a plasma processing apparatus 1 according to a first embodiment. The plasma processing apparatus 1 in Fig. 1 performs a desired process on a wafer W under a reduced pressure atmosphere (vacuum atmosphere). Specifically, the plasma processing apparatus 1 performs a plasma process on the wafer W, such as etching or film formation.

[0014] The plasma processing apparatus 1 includes a plasma processing chamber 100 as a processing container, gas supply units 120 and 130, an RF (Radio Frequency) power supply unit 140, and an exhaust system 150. The plasma processing apparatus 1 further includes a wafer support table 101 and an upper electrode 102 as a support unit.

[0015] The wafer support pedestal 101 is disposed in a lower region of a plasma processing space 100s in the plasma processing chamber 100, the interior of which can be depressurized. The upper electrode 102 is disposed above the wafer support pedestal 101. The upper electrode 102 may also function as part of a wall defining the plasma processing space 100s, and more specifically, may function as part of the ceiling of the plasma processing chamber 100.

[0016] The wafer support pedestal 101 is configured to support a wafer W in the plasma processing space 100s. In one embodiment, the wafer support pedestal 101 includes a lower electrode 103, an electrostatic chuck 104, an insulator 105, and legs 106, and is provided with a lifter 107. The wafer support pedestal 101 also controls the temperature of the electrostatic chuck 104 (for example, the temperature of the upper surface 104 at the center thereof). １ The temperature adjusting unit includes a temperature adjusting section configured to adjust the temperature of the heating element (temperature of the heating element), etc. The temperature adjusting section includes, for example, a heater, a flow path, or a combination thereof. A temperature adjusting fluid such as a refrigerant or a heat transfer gas flows through the flow path.

[0017] The lower electrode 103 is formed of a conductive material such as aluminum and is fixed to the insulator 105. In one embodiment, a flow path 108 for the temperature control fluid, which constitutes part of the temperature control unit, is formed inside the lower electrode 103. The temperature control fluid is supplied to the flow path 108 from, for example, a chiller unit (not shown) provided outside the plasma processing chamber 100. The temperature control fluid supplied to the flow path 108 returns to the chiller unit. For example, by circulating low-temperature brine as the temperature control fluid through the flow path 108, the electrostatic chuck 104 and the wafer W and edge ring E placed on the electrostatic chuck 104 can be cooled to a predetermined temperature. Furthermore, for example, by circulating high-temperature brine as the temperature control fluid through the flow path 108, the electrostatic chuck 104 and the wafer W and edge ring E placed on the electrostatic chuck 104 can be heated to a predetermined temperature.

[0018] The electrostatic chuck 104 is a member configured to be able to attract and hold the wafer W by electrostatic force, and is provided on the lower electrode 103. In one embodiment, the electrostatic chuck 104 is formed so that the upper surface of the central portion is higher than the upper surface of the peripheral portion. １ The upper surface 104 of the peripheral portion of the electrostatic chuck 104 is a wafer mounting surface on which the wafer W is mounted. ２ The edge ring E is mounted on the upper surface 104 of the central portion of the electrostatic chuck 104. １ The wafer W is placed adjacent to the wafer W so as to surround the wafer W placed on the support member 11.

[0019] The electrostatic chuck 104 has an upper surface 104 at the center thereof. １ That is, it is an example of a fixing portion that fixes the wafer W to the wafer mounting surface. An electrode 109 is provided at the center of the electrostatic chuck 104.

[0020] A DC voltage is applied to the electrode 109 from a DC power supply (not shown). The electrostatic force generated by this applies a DC voltage to the upper surface 104 of the central portion of the electrostatic chuck 104. １ In one embodiment, the electrostatic chuck 104 is configured to be able to attract and hold the edge ring E by electrostatic force, and is provided with an electrode (not shown) for holding the edge ring E to the wafer support table 101 by electrostatic attraction. ２ The upper surface 104 ２ Gas supply holes (not shown) are formed on the back surface of the edge ring E placed on the support member 10 for supplying a heat transfer gas such as He gas. The heat transfer gas is supplied from a gas supply unit (not shown) through the gas supply holes. The gas supply unit may include one or more gas sources and one or more pressure controllers. In one embodiment, the gas supply unit is configured to supply the heat transfer gas from the gas source to the gas supply holes via the pressure controller, for example.

[0021] The central portion of the electrostatic chuck 104 is formed to have a diameter smaller than that of the wafer W, for example, so that the wafer W is held on the upper surface (hereinafter referred to as the wafer mounting surface) 104 of the central portion of the electrostatic chuck 104. １ When the wafer W is placed on the electrostatic chuck 104, the peripheral edge of the wafer W protrudes beyond the center of the electrostatic chuck 104. The edge ring E has, for example, a step formed at its upper portion, so that the upper surface of the outer periphery is higher than the upper surface of the inner periphery. The inner periphery of the edge ring E is formed to be recessed below the peripheral edge of the wafer W protruding beyond the center of the electrostatic chuck 104.

[0022] The electrostatic chuck 104 may be provided with a heater (specifically, a resistance heating element) constituting part of a temperature adjustment unit. By applying current to the heater, the electrostatic chuck 104 and the wafer W placed on the electrostatic chuck 104 can be heated to a predetermined temperature. In this case, the electrostatic chuck 104 has a configuration in which the wafer attracting electrode 109 and the edge ring attracting electrode are sandwiched between insulating materials, and the heater is embedded therein. The central portion of the electrostatic chuck 104, on which the wafer attracting electrode 109 is provided, and the peripheral portion of the electrostatic chuck 104, on which the edge ring attracting electrode is provided, may be integrally formed or may be separate.

[0023] The insulator 105 is a disk-shaped member made of ceramic or the like, and the lower electrode 103 is fixed to the insulator 105. The insulator 105 is formed to have the same diameter as the lower electrode 103, for example.

[0024] The legs 106 are cylindrical members made of ceramic or the like, and support the electrostatic chuck 104 via the lower electrode 103 and the insulator 105. The legs 106 are formed to have an outer diameter equal to the outer diameter of the insulator 105, for example, and support the peripheral edge of the insulator 105.

[0025] The lifter 107 lifts the wafer-mounting surface 104 of the electrostatic chuck 104. １ The lifter 107 is a lifting member that moves up and down relative to the wafer placement surface 104 and is formed, for example, in a columnar shape. １The lifter 107 protrudes from the electrostatic chuck 104 and is capable of supporting the wafer W. The lifter 107 allows the wafer W to be transferred between the electrostatic chuck 104 and the transfer arm 71 of the transfer mechanism 70. Three or more lifters 107 are provided at intervals from each other and extend in the vertical direction.

[0026] Each lifter 107 is connected to a support member 110 that supports the lifter 107. The support member 110 is connected to a drive unit 111 that generates a drive force for raising and lowering the support member 110 and raises and lowers the plurality of lifters 107. The drive unit 111 has, for example, an actuator (not shown) as a drive source that generates the drive force.

[0027] The lifter 107 lifts the wafer-mounting surface 104 of the electrostatic chuck 104. １ The lifter 107, the support member 110, and the drive unit 111 are inserted into an insertion hole 112 that opens at the top end. The insertion hole 112 is formed to penetrate, for example, the center of the electrostatic chuck 104, the lower electrode 103, and the insulator 105. The lifter 107, the support member 110, and the drive unit 111 are connected to the wafer mounting surface 104. １ A lifting mechanism is provided for lifting the wafer W relative to the substrate.

[0028] The upper electrode 102 also functions as a showerhead that supplies various gases from the gas supply unit 120 to the plasma processing space 100s. In one embodiment, the upper electrode 102 has a gas inlet 102a, a gas diffusion chamber 102b, and multiple gas inlets 102c. The gas inlet 102a is, for example, in fluid communication with the gas supply unit 120 and the gas diffusion chamber 102b. The multiple gas inlets 102c are in fluid communication with the gas diffusion chamber 102b and the plasma processing space 100s. In one embodiment, the upper electrode 102 is configured to supply various gases from the gas inlet 102a to the plasma processing space 100s via the gas diffusion chamber 102b and the multiple gas inlets 102c.

[0029] The gas supply unit 120 may include one or more gas sources 121 and one or more flow controllers 122. In one embodiment, the gas supply unit 120 is configured to supply, for example, one or more process gases from the corresponding gas sources 121 to the gas inlet 102a via the corresponding flow controllers 122. Each flow controller 122 may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 120 may include one or more flow modulation devices that modulate or pulse the flow rate of one or more process gases. Also, in one embodiment, the gas supply unit 120 supplies N 2 O 3 to the plasma processing space 100s. ２ It functions as an inert gas supply unit that supplies an inert gas such as gas.

[0030] In one embodiment, a gas containing a source gas serving as a source material for the heat transfer layer D (described later), i.e., a heat transfer layer forming gas, is supplied from the gas supply unit 130 to the plasma processing space 100s through a sidewall of the plasma processing chamber 100. In this case, for example, a gas inlet 100k fluidly communicating with the plasma processing space 100s and the gas supply unit 130 is provided in the sidewall of the plasma processing chamber 100, and the heat transfer layer forming gas from the gas supply unit 130 is supplied to the plasma processing space 100s through the sidewall (specifically, the gas inlet 100k).

[0031] The gas supply unit 130 may include one or more gas sources 131 and one or more flow rate controllers 132. In one embodiment, the gas supply unit 130 is configured to supply, for example, a heat-transfer layer forming gas from the gas source 131 to the gas inlet 100k via the flow rate controller 132. The gas source 131 may include, for example, a tank 131a that stores a raw material liquid for the heat-transfer layer D and a vaporizer 131b that vaporizes the raw material liquid to generate a raw material gas. The gas source 131 may also be connected to a supply path (not shown) for an inert gas as a carrier gas. In this case, for example, a mixed gas of a raw material gas and a carrier gas is supplied from the gas source 131 as the heat-transfer layer forming gas. Each flow rate controller 132 may include, for example, a mass flow controller or a pressure-controlled flow rate controller. Furthermore, the gas supply unit 130 may include one or more flow rate modulation devices that modulate or pulse the flow rates of one or more heat-transfer layer forming gases. The gas for forming the heat transfer layer, which contains the raw material gas supplied from the gas supply unit 130, is used to form the wafer support surface 104 of the wafer support table 101, for example. １ A liquid heat transfer layer D is formed on the wafer mounting surface 104. １ It can function as at least a part of a heat transfer layer forming section configured to form a heat transfer layer D thereon.

[0032] The RF power supply 140 is configured to supply RF power, e.g., one or more RF signals, to one or more electrodes, such as the lower electrode 103, the upper electrode 102, or both the lower electrode 103 and the upper electrode 102. Alternatively, the RF power supply 140 may be configured to supply RF power to an electrode 109 disposed within the electrostatic chuck 104, instead of the lower electrode 103. This generates a plasma from one or more process gases supplied to the plasma processing space 100s. Thus, the RF power supply 140 may function as at least a part of a plasma generating unit configured to generate a plasma from one or more process gases in the plasma processing chamber 100.

[0033] The RF power supply 140 includes, for example, two RF generators 141 a, 141 b and two matching circuits 142 a, 142 b. In one embodiment, the RF power supply 140 is configured to supply a first RF signal from the first RF generator 141 a through the first matching circuit 142 a to the lower electrode 103. For example, the first RF signal may have a frequency in the range of 27 MHz to 100 MHz.

[0034] In one embodiment, the RF power supply unit 140 is configured to supply a second RF signal from a second RF generating unit 141b to the lower electrode 103 via a second matching circuit 142b. For example, the second RF signal may have a frequency within a range of 400 kHz to 13.56 MHz. A voltage pulse other than RF may be supplied instead of the second RF signal. The voltage pulse may be a negative DC voltage. In another example, the voltage pulse may be a triangular wave or an impulse.

[0035] Further, although not shown, other embodiments are contemplated in this disclosure. For example, in an alternative embodiment, the RF power supply 140 may be configured to supply a first RF signal from an RF generator to the lower electrode 103, a second RF signal from another RF generator to the lower electrode 103, and a third RF signal from yet another RF generator to the lower electrode 103. Additionally, in another alternative embodiment, a DC voltage may be applied to the upper electrode 102.

[0036] Still further, in various embodiments, the amplitude of one or more RF signals (i.e., the first RF signal, the second RF signal, etc.) may be pulsed or modulated. Amplitude modulation may include pulsing the RF signal amplitude between an on state and an off state, or between two or more different on states.

[0037] The exhaust system 150 includes an exhaust line 160 that exhausts air from the plasma processing space 100 s and a bypass line 170 that bypasses the exhaust line 160 .

[0038] The upstream end of the exhaust line 160 is connected to, for example, an exhaust port 100e provided at the bottom of the plasma processing chamber 100. Pumps are provided in the exhaust line 160, and more specifically, for example, a turbomolecular pump 161 serving as a first exhaust pump and a dry pump 162 serving as a second exhaust pump are provided in this order from the upstream side. In one embodiment, an automatic pressure control (APC) valve 163 is provided in the exhaust line 160 upstream of the turbomolecular pump 161, and an on-off valve 164 is provided in the exhaust line 160 between the turbomolecular pump 161 and the dry pump 162. The automatic pressure control valve 163 has, for example, an automatic pressure adjustment function and a shut-off function.

[0039] As described above, the bypass line 170 bypasses the exhaust line 160. Specifically, the bypass line 170 bypasses the upstream side of the exhaust line 160, more specifically, the portion of the exhaust line 160 where the turbomolecular pump 161 is provided. The upstream end of the bypass line 170 is connected, for example, to the upstream side of the turbomolecular pump 161 in the exhaust line 160, specifically, to the upstream side of the automatic pressure control valve 163 in the exhaust line 160. The downstream end of the bypass line 170 is connected, for example, to the exhaust line 160 between the turbomolecular pump 161 and the dry pump 162, specifically, to the exhaust line 160 between the on-off valve 164 and the dry pump 162. This configuration makes it possible to exhaust gas from the plasma processing space 100s via the bypass line 170.

[0040] Furthermore, a trap 171 is provided in the bypass line 170 to collect gaseous heat transfer layer D contained in the exhaust gas from the plasma processing space 100s. The gaseous heat transfer layer D collected in the trap 171 is at least one of a source gas of the heat transfer layer D and a vaporized product of the heat transfer layer D. In one embodiment, an on-off valve 172 is provided upstream of the trap 171 in the bypass line 170, and a pressure adjustment valve 173 and an on-off valve 174 are provided downstream of the bypass line 170, in this order from the upstream side.

[0041] The plasma processing apparatus 1 further includes a control unit 200. In one embodiment, the control unit 200 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The control unit 200 may be configured to control each of the other elements of the plasma processing apparatus 1 to perform various processes described herein. In one embodiment, a part or all of the control unit 200 may be included in the plasma processing apparatus 1. The control unit 200 may include a processing unit 211, a storage unit 212, and a communication interface 213. The control unit 200 is implemented, for example, by a computer 210. The processing unit 211 may be configured to read a program from the storage unit 212 and execute the read program to perform various control operations. The program may be stored in the storage unit 212 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 212 and read from the storage unit 212 by the processing unit 211 for execution. The medium may be various storage media readable by the computer 210 or a communication line connected to the communication interface. The processing unit 211 may be a central processing unit (CPU) or one or more circuits. The storage unit 212 may include a random access memory (RAM), a read only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 213 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0042] <Wafer Processing in Plasma Processing Apparatus 1> Next, an example of wafer processing performed using the plasma processing apparatus 1 will be described with reference to FIGS. 2 to 9. FIG. 2 is a flowchart for explaining this example of wafer processing. FIGS. 3 to 6, 8, and 9 are diagrams showing the state of the plasma processing apparatus 1 during the wafer processing. In FIGS. 3 to 6, 8, and 9, open valves are painted white, closed valves are painted black, and pipes such as exhaust lines through which liquids and gases flow are indicated by thick lines. FIG. 7 is a diagram showing vapor pressure curves of the constituent materials of the heat transfer layer D.

[0043] The following wafer processing is performed under the control of the control unit 200. During the wafer processing, the temperature Tt of the trap 171 (specifically, the temperature of the space where the gas is liquefied and collected) is maintained at a temperature at which the gaseous heat transfer layer D is easily liquefied, for example, a preset temperature in the range of -100°C to 25°C. During the wafer processing, the temperature of the wafer support table 101 (specifically, the temperature of the wafer placement surface 104 １ The temperature Ts of the plasma processing chamber (hereinafter referred to as the processing chamber) 100 is maintained at a temperature during plasma processing, for example, a preset temperature in the range of −80° C. to 80° C. Furthermore, during wafer processing, the sidewall and upper electrode 102 of the plasma processing chamber (hereinafter referred to as the processing chamber) 100 defining the plasma processing space (hereinafter referred to as the processing space) 100s are maintained at a temperature at which the gaseous heat transfer layer D is unlikely to liquefy, for example, a preset temperature in the range of 25° C. to 150° C.

[0044] (Step S1: Formation of Heat Transfer Layer) For example, as shown in FIG. 2, first, the wafer mounting surface 104 of the wafer support table 101 is １ A heat transfer layer D is formed thereon.

[0045] In this embodiment, the material of the heat transfer layer D is a material that is liquid at temperature T1 and pressure P2, and gases at pressure P1, as shown in FIG. 7. A suitable material for practical use is one that satisfies the temperature T1 range of -80°C to 80°C, the pressure P2 range of 0.01 Torr to 10 Torr, and the pressure P1 range of less than 0.01 Torr. An example of such a material is methyl benzoate. Furthermore, in this embodiment, as will be described later, the wafer W is placed on the wafer mounting surface 104 via the heat transfer layer D. １ Since the heat transfer layer D is placed on the wafer W, the heat transfer layer D has a high surface tension in a liquid state so that the heat transfer layer D in a liquid state does not flow around onto the surface, i.e., the upper surface, of the wafer W. The term "liquid" also includes sols and gels that use a liquid as a dispersion medium.

[0046] Furthermore, the raw material gas for the heat transfer layer D contains, for example, at least one of B (boron) and C (carbon), which are constituent atoms of the heat transfer layer D, and at least one of H (hydrogen), N (nitrogen), and O (oxygen), which are constituent gas components. In addition, the raw material gas for the heat transfer layer D preferably contains components that do not interfere with plasma treatment.

[0047] Specifically, when forming the heat transfer layer D, first, the interior of the processing chamber 100, i.e., the processing space 100s, is evacuated. More specifically, as shown in FIG. 3 , with no processing gas supplied from the gas supply unit 120 or no heat transfer layer forming gas supplied from the gas supply unit 130, the automatic pressure control valve 163 of the exhaust line 160 is fully opened and the on-off valve 164 is opened. This allows the turbomolecular pump 161 and the dry pump 162 to evacuate the interior of the processing chamber 100, i.e., the processing space 100s, and the interior of the processing chamber 100 is depressurized to, for example, an achievable vacuum level. At this time, the on-off valve 172, the pressure control valve 173, and the on-off valve 174 provided in the bypass line 170 are closed. That is, the processing space 100s is not evacuated via the bypass line 170.

[0048] Next, the wafer W is loaded into the processing chamber 100. Specifically, for example, as shown in FIG. 4 , the automatic pressure control valve 163 and the on-off valve 164 of the exhaust line 160 are switched to a closed state so that exhaust of the processing space 100s via the exhaust line 160 is stopped. Furthermore, the on-off valves 172 and 174 of the bypass line 170 are opened, and the pressure control valve 173 is fully opened. That is, exhaust of the processing space 100s via the bypass line 170 is started. Thereafter, the wafer W is loaded into the processing chamber 100 by a transfer mechanism (not shown) external to the plasma processing apparatus 1 and transferred to the raised lifter 107. After the transfer, the transfer mechanism is retracted from the processing chamber 100.

[0049] Subsequently, the source gas for the heat transfer layer D is supplied into the processing chamber 100. Specifically, for example, as shown in FIG. 5, the wafer W is supported by the lifter 107 and the wafer support surface 104 of the wafer support table 101 is １ In a state where the processing space 100s is separated from the processing chamber 100a and the processing space 100s is evacuated via the bypass line 170, a heat transfer layer forming gas containing a source gas is supplied from the gas supply unit 130. At this time, in the illustrated example, no processing gas is supplied from the gas supply unit 120. By supplying the heat transfer layer forming gas as described above, the atmosphere in the processing space 100s is replaced with the heat transfer layer forming gas. During this replacement, the pressure value in the processing space 100s reaches P1, and the temperature of the wafer support table 101 (specifically, the wafer mounting surface 104 １ The pressure value P1 is a pressure value at which the source gas for the heat transfer layer D becomes less than the saturated vapor pressure at the temperature T1, and for example, the temperature T1 is −80° C. to 80° C., and P1 is less than 0.01 Torr. The temperature Ts of the wafer support table 101 is set by a temperature adjustment unit of the wafer support table 101, and the pressure in the processing space 100s is set by adjusting at least one of the flow rate of the heat transfer layer forming gas or the exhaust rate via the bypass line 170 (specifically, the opening of the pressure adjustment valve 173).

[0050] During the above-described replacement, the source gas for the heat-transfer layer D in the heat-transfer-layer forming gas that has reached the bypass line 170 is condensed and recovered by the trap 171. In order to condense the source gas for the heat-transfer layer D by the trap 171, the temperature of the trap 171 is set to Tt. The temperature Tt is lower than the temperature at which the source gas liquefies at the pressure P1 and is lower than the temperature T1 (Ts).

[0051] Thereafter, the pressure inside the processing chamber 100 is increased, and the wafer support surface 104 of the wafer support table 101 １ 6, the wafer W is supported by the lifter 107 and the wafer support surface 104 of the wafer support table 101 is formed on the wafer W. １ With the processing space 100s separated from the wafer support table 101 and the heat transfer layer forming gas being supplied from the gas supply unit 130, the on-off valves 172 and 174 of the bypass line 170 are switched to a closed state. This stops exhaust from the processing space 100s, including exhaust via the bypass line 170, and the pressure value within the processing space 100s is increased to P2. The pressure value P2 is a pressure value higher than the saturated vapor pressure of the source gas for the heat transfer layer D at the temperature Ts of the wafer support table 101, and is, for example, 0.01 to 10 Torr. As a result of the pressure increase, the source gas for the heat transfer layer D condenses on the surface of the wafer support table 101, and the condensation of the source gas for the heat transfer layer D is increased to at least the wafer mounting surface 104. １ After the heat transfer layer D is formed, the supply of the heat transfer layer forming gas from the gas supply unit 130 is stopped.

[0052] The wafer placement surface 104 １ In order to prevent the heat transfer layer D from being formed in the area other than the wafer mounting surface 104 １ The temperature of a region other than the pressure value P2 may be set to Tw. For example, heaters may be provided on the sidewalls and upper electrode 102 of the plasma processing chamber 100, and the temperatures of the sidewalls and upper electrode 102 of the plasma processing chamber 100 may be adjusted to Tw. The temperature Tw is higher than the temperature at which the source gas liquefies at the pressure value P2, and is higher than the temperature T1 (Ts).

[0053] (Step S2: Wafer Placement) Next, the wafer placement surface 104 of the wafer support table 101１ A wafer W is placed thereon.

[0054] Specifically, for example, first, the lifter 107 is lowered, and the wafer W is placed on the wafer mounting surface 104 of the electrostatic chuck 104 as shown in FIG. １ The wafer is placed on the wafer support table 101 via the liquid heat transfer layer D. １ The heat transfer layer D formed in the other portions is removed. Specifically, the on-off valves 172 and 174 of the bypass line 170 are switched to an open state so that the processing space 100s is evacuated via the bypass line 170. By evacuating the processing space 100s via the bypass line 170, the pressure in the processing space 100s is reduced to the pressure on the wafer mounting surface 104 of the wafer support table 101. １ The pressure is set to be less than the saturated vapor pressure of the source gas in the heat transfer layer D relative to the set temperature of the wafer placement surface 104. １ While maintaining the temperature Ts at T1, the pressure value of the processing space 100s is set to the aforementioned P1. １ The heat transfer layer D formed on the other part of the wafer mounting surface 104 is exposed to the reduced pressure atmosphere, and as a result, is vaporized and removed. １ In order to suppress evaporation of the heat transfer layer D formed on the wafer mounting surface 104, １ Specifically, a DC voltage may be applied to the electrode 109 of the electrostatic chuck 104, and the wafer W may be electrostatically attracted to the electrostatic chuck 104 by electrostatic force.

[0055] During the removal of the heat transfer layer D, the vaporized material of the heat transfer layer D that has reached the bypass line 170 is condensed and collected by the trap 171. In order to condense the vaporized material of the heat transfer layer D by the trap 171, the temperature of the trap 171 is set to Tt. The temperature Tt is lower than the temperature at which the raw material gas liquefies at the pressure P1 and is lower than the temperature T1 (Ts).

[0056] (Step S3: Plasma treatment) After that, the wafer mounting surface 104 on which the heat transfer layer D is formed is １ The upper wafer W is subjected to plasma processing such as etching and film formation.

[0057] 9 , first, evacuation of the processing space 100s via the bypass line 170 is stopped, and then evacuation of the processing space 100s via the exhaust line 160 is started by switching the on-off valves 172 and 174 of the bypass line 170 to an open state and switching the on-off valve 164 of the exhaust line 160 to an open state. Next, a processing gas is supplied from the gas supply unit 120 to the processing space 100s via the upper electrode 102, and high-frequency power HF for plasma generation is supplied from the RF power supply unit 140 to the lower electrode 103. This excites the processing gas, generating plasma P. At this time, high-frequency power LF for ion attraction may also be supplied from the RF power supply unit 140. Then, plasma processing is performed on the wafer W by the action of the generated plasma P.

[0058] During the plasma processing, the wafer mounting surface 104 １ The temperature of the wafer W is adjusted to a predetermined temperature by a temperature control fluid flowing through the flow path 108. During plasma processing, the wafer W is transferred to the wafer mounting surface 104 via the liquid heat transfer layer D. １ Since the heat transfer layer D is made of a deformable liquid, the lower surface, i.e., the back surface, of the wafer W is in close contact with the heat transfer layer D. Since the heat transfer layer D is a liquid, it has higher thermal conductivity than a heat transfer gas such as He. Therefore, when a liquid heat transfer layer D is used, it is not possible to inject a heat transfer gas such as He onto the wafer mounting surface 104 as in the conventional method. １ and the back surface of the wafer W, １ Specifically, even if the heat input from the plasma P to the wafer W is large during the plasma processing, the temperature of the wafer W can be efficiently adjusted by the wafer mounting surface 104. １ Through this temperature control, the temperature of the wafer W can be maintained constant.

[0059] During plasma processing, in order to bring the heat transfer layer D and the lower surface of the wafer W into closer contact with each other, the wafer W is supported on the wafer support table 101 (specifically, the wafer mounting surface 104 １ For example, the wafer W may be held or fixed to the wafer mounting surface 104 by the electrostatic force of the electrostatic chuck 104.１ The wafer W may be attracted and held by the electrostatic chuck 104. More specifically, a DC voltage may be applied to the electrode 109 of the electrostatic chuck 104, and the wafer W may be electrostatically attracted to the electrostatic chuck 104 by electrostatic force. By holding the wafer W in the above manner, the temperature of the wafer W can be adjusted more efficiently. When the wafer W is held on the wafer support table 101 by electrostatic force, the degree of adhesion of the wafer W to the wafer support table 101 may be controlled by the electrostatic force, thereby controlling heat removal from the wafer W by the wafer support table 101.

[0060] Similarly, during plasma processing, the edge ring E may be held or fixed to the wafer support table 101. For example, a DC voltage may be applied to an electrode (not shown) for attracting the edge ring provided on the electrostatic chuck 104, so that the edge ring E is electrostatically attracted to the electrostatic chuck 104 by electrostatic force. Also, during plasma processing, the upper surface 104 of the peripheral portion of the electrostatic chuck 104 may be turned toward the back surface of the edge ring E. ２ Heat transfer gas may be supplied through gas supply holes (not shown) formed in the nozzle.

[0061] When plasma processing is terminated, the supply of high-frequency power HF from the RF power supply unit 140 and the supply of processing gas from the gas supply unit 130 are stopped. If high-frequency power LF has been supplied during plasma processing, the supply of the high-frequency power LF is also stopped. Furthermore, if the electrostatic chuck 104 has been attracting and holding the wafer W during plasma processing, the attracting and holding is also stopped. Note that if the electrostatic chuck 104 has been attracting and holding the edge ring E and a heat transfer gas has been supplied to the back surface of the edge ring E during plasma processing, at least one of these may be stopped.

[0062] (Step S4: Wafer Separation) After the plasma processing, the wafer W is separated from the wafer mounting surface 104. １ be isolated from

[0063] Specifically, for example, as shown in FIG. 4, the wafer W is lifted by the lifter 107 and placed on the wafer placement surface 104. １The processing space 100s is separated from the upper heat transfer layer D. Furthermore, the automatic pressure control valve 163 and the on-off valve 164 of the exhaust line 160 are switched to a closed state so that exhaust of the processing space 100s via the exhaust line 160 is stopped. Furthermore, the on-off valves 172 and 174 of the bypass line 170 are switched to an open state so that exhaust of the processing space 100s via the bypass line 170 is started.

[0064] (Step S5: Removal of the heat transfer layer) Then, the wafer mounting surface 104 １ The heat transfer layer D is removed from the substrate (step S6).

[0065] Specifically, the processing space 100s continues to be evacuated via the bypass line 170, and the pressure in the processing space 100s is made less than the saturated vapor pressure of the source gas in the heat transfer layer D at the temperature Ts of the wafer support table 101. １ The heat transfer layer D formed on the substrate 170 is exposed to a reduced pressure atmosphere, and as a result, is vaporized and removed. During the removal of the heat transfer layer D, the vaporized material of the heat transfer layer D that reaches the bypass line 170 is condensed and collected by the trap 171. In order to condense the vaporized material of the heat transfer layer D by the trap 171, the following adjustment is made. That is, the amount of exhaust gas through the bypass line 170 is adjusted so that the pressure of the trap 171 exceeds the saturated vapor pressure of the source gas for the temperature Tt of the trap 171, specifically, so that it exceeds 0.01 Torr.

[0066] wafer placement surface 104 １ When the heat transfer layer D is removed from the wafer support surface 104, the edge ring E may be held or fixed to the wafer support table 101. For example, a DC voltage may be applied to an electrode (not shown) for attracting the edge ring provided on the electrostatic chuck 104, so that the edge ring E is electrostatically attracted to the electrostatic chuck 104 by electrostatic force. １ During removal of the heat transfer layer D from the electrostatic chuck 104, the upper surface 104 of the peripheral portion of the electrostatic chuck 104 is ２ Heat transfer gas may be supplied through gas supply holes (not shown) formed in the nozzle.

[0067] (Step S6: Wafer Unloading) Thereafter, the wafer W is unloaded from the processing chamber 100. Specifically, for example, while the processing space 100s continues to be evacuated via the bypass line 170, the wafer W is transferred via the lifter 107 to a transfer mechanism (not shown) outside the plasma processing apparatus 1, and is unloaded from the processing chamber 100 by the transfer mechanism. Thereafter, the process returns to step S1, and the processing space 100s is evacuated via the exhaust line 160, and, for example, the inside of the processing chamber 100 is depressurized to an achievable vacuum level. In this manner, a series of wafer processing steps is completed.

[0068] <Other Examples of Heat Transfer Layer D> In the above examples, the heat transfer layer D is formed as a liquid by condensing (liquefying) the source gas of the heat transfer layer D. However, the heat transfer layer D may be a solid layer as long as it is deformable. That is, the source gas of the heat transfer layer D may be sublimated (solidified) to form a deformable solid heat transfer layer D. Here, "deformable" means, for example, being deformable due to the weight of the wafer W. Furthermore, in the case where the wafer W is electrostatically attracted by the electrostatic chuck 104, "deformable" may also mean being deformable when an electrostatic attraction force acts on the wafer W. Furthermore, the heat transfer layer D may be a combination of a liquid layer and a solid layer as long as it is deformable.

[0069] That is, the heat transfer layer D is a deformable layer composed of at least one of a liquid layer and a solid layer. Note that the heat transfer layer D may have a top layer in contact with the backside of the wafer W that is deformable composed of a liquid layer, a solid layer, or a combination of these, and other portions that are solid layers that do not deform.

[0070] The solid constituting the heat transfer layer D may have an elastic modulus that allows it to be deformed freely by the weight of the wafer W, or may have an elastic modulus that allows it to be deformed freely when an electrostatic adsorption force acts on the wafer W. More specifically, the solid constituting the heat transfer layer D is, for example, an elastic polymeric substance, i.e., an elastomer.

[0071] <Effects, etc.> As described above, in this embodiment, the wafer mounting surface 104 of the wafer support table 101 １A deformable heat transfer layer D made of at least one of a liquid layer and a solid layer is formed on the wafer mounting surface 104. １ The wafer W is subjected to plasma processing. The heat transfer layer D is made of at least one of a liquid layer and a solid layer, and therefore has a higher thermal conductivity than a heat transfer layer made of a heat transfer gas, i.e., a gas. In addition, the heat transfer layer D is deformable, and therefore can be in close contact with the lower surface of the wafer W. Therefore, according to this embodiment, the wafer W and the wafer mounting surface 104 １ Heat can be efficiently exchanged between the wafer mounting surface 104 and the heat transfer layer D. １ Specifically, during plasma processing, the temperature of the wafer W can be efficiently adjusted through the wafer mounting surface 104. １ This allows efficient heat absorption from the wafer W via the heat transfer layer D, and the wafer mounting surface 104 １ The wafer W can be efficiently heated via the heat transfer layer D. Furthermore, in this embodiment, a bypass line 170 is provided that bypasses the exhaust line 160 that exhausts the processing space 100s, and the bypass line 170 is provided with a trap 171 that collects the gaseous heat transfer layer D contained in the exhaust from the processing space 100s. This prevents the gaseous heat transfer layer D from reaching the pump of the exhaust line 160. This prevents the gaseous heat transfer layer from adversely affecting the pump of the exhaust line 160. Furthermore, compared to when the bypass line 170 is not provided, the frequency of cleaning the pump of the exhaust line 160 can be reduced, thereby improving throughput.

[0072] <Wafer placement surface 104 １ 10 and 11 show the wafer placement surface 104 １ 1 is a partially enlarged cross-sectional view of the wafer placement surface 104. １ The wafer mounting surface 104 is formed flat on its entire surface as shown in FIG. １ 11, the wafer mounting surface 104 may be subjected to a roughening treatment.１ The surface roughness of the roughened portion is, for example, 1 μm to 10 μm in arithmetic mean roughness Ra. The roughened portion has an increased surface area, and the wafer mounting surface 104 １ The heat is more efficiently transferred to the wafer W through the heat transfer layer D. １ The temperature of the wafer W can be adjusted more efficiently via the heat transfer layer D. The surface roughening treatment is performed by, for example, shot blasting or laser processing.

[0073] As will be described later, the heat transfer layer D may be formed from a heat transfer medium composed of at least one of a liquid medium and a solid medium having fluidity. In this case, the heat transfer medium is formed on the wafer mounting surface 104. １ To prevent leakage from the wafer mounting surface 104 １ along the peripheral edge of the wafer placement surface 104 １ In this embodiment, an annular convex portion may be provided concentric with the wafer placement surface 104. １ In this case, the surface roughening treatment may be performed only on the portion excluding the peripheral edge where the annular convex portion is formed, i.e., the portion where the heat transfer layer D is formed. Even if the annular convex portion is not provided, the wafer mounting surface 104 １ The wafer mounting surface 104 may have a roughened portion and a non-roughened portion. １ The central portion of the wafer may be an unroughened region and the peripheral portion may be a roughened region, thereby creating a temperature difference between the central portion and the peripheral portion of the wafer.

[0074] <Another Example of the Bypass Line 170> Fig. 12 is a diagram illustrating another example of the bypass line 170. As shown in Fig. 12, a return line 180 may be connected to the bypass line 170. The return line 180 is configured to return the source gas for the heat-transfer layer D recovered in the trap 171 to the gas supply unit 130. Specifically, the return line 180 is configured to return the source liquid for the heat-transfer layer D, which is produced by condensing the source gas for the heat-transfer layer D in the trap 171, to the tank 131a of the gas supply unit 130. The return line 180 may be provided with a pump 181 that sucks the source liquid for the heat-transfer layer D in the trap 171 and pumps it to the tank 131a of the gas supply unit 130. The return line 180 may also be provided with a filter 182 that removes foreign matter from the source liquid for the heat-transfer layer D.

[0075] The raw material liquid for the heat transfer layer D is returned from the trap 171 to the tank 131a when the trap 171 is not in communication with the processing space 100s, for example, when the plasma processing apparatus 1 is idling or during plasma processing.

[0076] By providing the return line 180 as described above, the recovered raw material gas from the heat transfer layer D can be effectively utilized.

[0077] 13 to 15 are diagrams illustrating other examples of the configuration in which the source gas for the heat transfer layer D is condensed on the surface of the wafer support pedestal 101. In the above examples, after the atmosphere in the processing space 100s is replaced with the heat transfer layer forming gas, exhaust from the processing space 100s, including exhaust via the bypass line 170, is stopped, and the heat transfer layer forming gas is supplied from the gas supply unit 130 without supplying the processing gas from the gas supply unit 120. This increases the pressure in the processing space 100s, causing the source gas for the heat transfer layer D to condense on the surface of the wafer support pedestal 101. In this configuration, the heat transfer layer D can be efficiently formed from the source gas for the heat transfer layer D supplied to the processing space 100s, because the heat transfer layer forming gas is not exhausted from the processing space 100s during the formation of the heat transfer layer D.

[0078] The manner in which the source gas for the heat transfer layer D is condensed on the surface of the wafer support table 101 is not limited to this. For example, as shown in FIG. 13 , when forming the heat transfer layer D, in a state in which exhaust from the processing space 100s, including exhaust via the bypass line 170, is stopped, in addition to supplying the heat transfer layer forming gas from the gas supply unit 130, an inert gas (e.g., N ) from the gas supply unit 120 is supplied. ２ In this configuration, the pressure in the processing space 100s can be increased to condense the source gas in the heat transfer layer D on the surface of the wafer support pedestal 101. Specifically, in this configuration, the pressure in the processing space 100s can be increased to exceed the saturated vapor pressure of the source gas in the heat transfer layer D at the temperature Ts of the wafer support pedestal 101, condensing the source gas in the heat transfer layer D on the surface of the wafer support pedestal 101 and condensing the source gas in the heat transfer layer D on at least the wafer mounting surface 104. １ In this embodiment, the heat transfer layer D can be efficiently formed from the source gas for the heat transfer layer D supplied to the processing space 100s.

[0079] 14 , after the atmosphere in the processing space 100s is replaced with the heat-transfer-layer-forming gas, both the inert gas from the gas supply unit 120 and the heat-transfer-layer-forming gas from the gas supply unit 130 may be supplied to the processing space 100s while the processing space 100s is being exhausted via the bypass line 170 without being exhausted via the exhaust line 160. In this configuration, the pressure in the processing space 100s can be increased to condense the source gas for the heat transfer layer D on the surface of the wafer support pedestal 101. Specifically, in this configuration, the pressure in the processing space 100s can be increased to exceed the saturated vapor pressure of the source gas for the heat transfer layer D at the temperature Ts of the wafer support pedestal 101, to condense the source gas for the heat transfer layer D on the surface of the wafer support pedestal 101, and the source gas for the heat transfer layer D can be condensed on at least the wafer mounting surface 104. １ In this configuration, even if the pressure in the processing space 100s increases, the pressure in the supply path connecting the gas supply unit 130 and the processing chamber 100 is unlikely to increase, so that the source gas of the heat transfer layer D can be prevented from condensing on the inner wall surface of the supply path.

[0080] 15 , after the atmosphere in the processing space 100s is replaced with the heat-transfer layer forming gas, only the inert gas from the gas supply unit 120 may be supplied to the processing space 100s while exhausting the processing space 100s through the bypass line 170 without exhausting the processing space 100s through the exhaust line 160. In this configuration, too, the pressure in the processing space 100s can be increased to condense the source gas for the heat transfer layer D on the surface of the wafer support pedestal 101. Specifically, in this configuration, too, the pressure in the processing space 100s is increased to exceed the saturated vapor pressure of the source gas for the heat transfer layer D at the temperature Ts of the wafer support pedestal 101, so that the source gas for the heat transfer layer D condenses on the surface of the wafer support pedestal 101, and the source gas for the heat transfer layer D condenses on at least the wafer support surface 104. １ A liquid heat transfer layer D can be formed in the processing space 100s. Furthermore, in this configuration, the pressure in the processing space 100s can be adjusted not only by the aperture of the pressure adjustment valve 173 downstream of the trap 171 but also by the flow rate of the inert gas from the gas supply unit 120, i.e., the flow rate of the inert gas from the upper electrode 102. Since the upper electrode 102 is closer to the processing space 100s than the pressure adjustment valve 173, this configuration improves the responsiveness of the pressure adjustment in the processing space 100s. Furthermore, in this configuration, when the pressure in the processing space 100s increases, the supply path connecting the gas supply unit 130 and the processing chamber 100 is separated from the processing space 100s. Therefore, when the pressure in the processing space 100s increases, condensation of the source gas of the heat transfer layer D on the inner wall surface of the supply path can be suppressed.

[0081] In addition, the wafer mounting surface 104 of the wafer support table 101 １ A thin heater (not shown) with a small heat capacity may be provided in a portion near the wafer mounting surface 104, for example, in the electrostatic chuck 104, as follows: That is, when the atmosphere in the processing space 100s is replaced with the heat transfer layer forming gas, the entire electrostatic chuck 104 is cooled by low-temperature brine circulating through the flow path 108, and the thin heater heats the wafer mounting surface 104. １In the stage of forming the heat transfer layer D, the heating by the thin heater may be stopped while the entire electrostatic chuck 104 is kept cooled. １ The temperature of the wafer mounting surface 104 drops instantaneously. １ In this case, the wafer W is placed on the wafer mounting surface 104 through the heat transfer layer D. １ When the wafer is placed on the wafer placement surface 104 and plasma processing is performed, heating by the thin heater is resumed. １ is adjusted to a temperature suitable for plasma treatment.

[0082] <Modification 1 of the Gas Supply Unit for Heat-Transfer-Layer Forming Gas> FIG. 16 is a diagram showing Modification 1 of the gas supply unit for the heat-transfer-layer forming gas. As described above, the gas supply unit 130 for the heat-transfer-layer forming gas may include a flow rate controller 132. Furthermore, the gas supply unit for the heat-transfer-layer forming gas may include an automatic pressure control (APC) valve 133 as a pressure control valve instead of the flow rate controller 132, as in the gas supply unit 130A of FIG. 16 . This automatic pressure control valve 133 has, for example, an automatic pressure control function and a shutoff function. By including the flow rate controller 132 or the automatic pressure control valve 133 in the gas supply unit for the heat-transfer-layer forming gas, it is possible to control the amount of source gas contained in the heat-transfer-layer forming gas supplied into the processing chamber 100.

[0083] <Variation 2 of Gas Supply Unit for Heat-Transfer Layer Forming Gas> In the above example, a mixed gas of a source gas and a carrier gas is supplied as the heat-transfer layer forming gas from the gas source 131 having the tank 131a storing the source liquid for the heat-transfer layer D in the gas supply unit for the heat-transfer layer forming gas. That is, the carrier gas is used to introduce the source gas into the processing chamber 100. However, the source gas may be introduced into the processing chamber 100 without using the carrier gas. In this case, for example, after the source liquid is vaporized in the tank 131a by reducing the pressure or the like to generate the source gas, a valve (e.g., automatic pressure regulating valve 133) separating the tank 131a and the processing chamber 100 is opened, and the source gas is introduced from the tank 131a into the processing chamber 100 due to the pressure difference between the tank 131a and the processing chamber 100. Furthermore, during this introduction, exhaust from within the processing chamber 100 may be stopped (i.e., both the automatic pressure control valve 163 and the on-off valve 172 may be closed) or may be performed (i.e., of the automatic pressure control valve 163 and the on-off valve 172, only the on-off valve 172 may be closed).

[0084] <Variations of Source Gas Supply Form> In the above examples, the source gas is supplied to the processing space 100s through the sidewall of the processing chamber 100. However, the source gas may be supplied through a wall defining the processing space 100s other than the sidewall of the processing chamber 100. For example, the heat transfer layer forming gas containing the source gas may be supplied through the upper electrode 102 that is also used to supply the processing gas. In this case, the gas outlet of the upper electrode 102 used to supply the processing gas and the gas outlet used to supply the heat transfer layer forming gas may be different or the same.

[0085] Furthermore, the source gas may be supplied to the processing space 100s via a wafer support table that supports the wafer W or a lifter that raises and lowers the wafer W.

[0086] <Modification of Formation of Heat Transfer Layer D from Source Gas> In the above examples, the heat transfer layer D is formed by at least one of liquefaction and solidification (i.e., condensation or sublimation) of the source gas, but the form of forming the heat transfer layer D from the source gas is not limited to this. For example, the heat transfer layer D may be formed from the source gas using plasma.

[0087] Alternatively, the heat transfer layer D may be formed by irradiating the source gas in the plasma processing space 100s with light to cause at least one of liquefaction and solidification of the source gas.

[0088] <Wafer placement surface 104 １ Modification of the form of removing the heat transfer layer D formed other than on the wafer mounting surface 104> In the above example, by exposing the wafer mounting surface 104 to a reduced pressure atmosphere, １ Although the heat transfer layer D formed other than the above is removed, the manner of removal is not limited to this.

[0089] For example, plasma is used to heat the wafer mounting surface 104 １ The heat transfer layer D formed on the other part may be removed. １ Alternatively, the heat transfer layer D formed on the other portions may be vaporized and selectively removed by irradiating the heat transfer layer D with light.

[0090] <Wafer placement surface 104 １ In the above example, the heat transfer layer D formed on the wafer mounting surface 104 is removed by exposing the wafer mounting surface 104 to a reduced pressure atmosphere. １ However, the form of the removal is not limited to this.

[0091] For example, plasma is used to heat the wafer mounting surface 104 １ The heat transfer layer D formed on the wafer mounting surface 104 may be removed. １ The heat transfer layer D formed on the wafer mounting surface 104 may be vaporized and selectively removed by irradiating the heat transfer layer D with light. １ The heat transfer layer D formed on the wafer mounting surface may be vaporized and removed by raising the temperature.

[0092] <Other examples of the state inside the processing chamber 100 when forming the heat transfer layer D> In the above examples, the wafer W was located inside the processing chamber 100 when forming the heat transfer layer D, but it does not have to be located inside the processing chamber 100.

[0093] <Other Examples of Materials for Heat Transfer Layer D> In the above examples, the wafer mounting surface 104 １ The raw material for the heat transfer layer D is gas in the above embodiment, but it may be a heat transfer medium composed of at least one of a liquid medium and a solid medium having fluidity.

[0094] In this case, as shown in FIG. 17, the wafer support table 101B is connected to the wafer placement surface 104B. １ Specifically, for example, the heat transfer medium is supplied to the wafer placement surface 104B. １ through a supply port 300 formed in the wafer placement surface 104B. １ The heat transfer medium is supplied to the center of the wafer placement surface 104B. １ A plurality of such sensors may be provided.

[0095] In this case, a flow path 310 is provided inside the wafer support table 101B, one end of which is fluidly connected to the supply port 300. The other end of the flow path 310 is fluidly connected to, for example, a gas supply unit 130B. １ The end portion of the flow path 310 (specifically, the portion located inside the electrostatic chuck 104B) is formed to be thin, and the heat transfer medium in the flow path 310 flows through the supply port 300 to the wafer placement surface 104B by capillary action. １ The flow path 310 is formed so as to extend over, for example, the electrostatic chuck 104B, the lower electrode 103B, and the insulator 105B.

[0096] The gas supply unit 130B may include one or more gas sources 131B and one or more flow controllers 132B. In one embodiment, the gas supply unit 130EB is configured to supply, for example, one or more gases for generating the heat transfer medium (hereinafter referred to as heat transfer medium generating gases) from the corresponding gas sources 131B to the wafer support pedestal 101B via the corresponding flow controllers 132B. Each flow controller 132B may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 130B may include one or more flow modulation devices that modulate or pulse the flow rates of the one or more heat transfer medium generating gases.

[0097] The heat transfer medium generating gas supplied from the gas supply unit 130B is cooled in the flow path 310 by, for example, the lower electrode 103B cooled by the temperature control fluid, and is liquefied or solidified to become a heat transfer medium composed of at least one of a liquid medium and a solid medium having fluidity. As described above, this heat transfer medium flows through the supply port 300 to the wafer mounting surface 104B by, for example, capillary action. １ The gas supply unit 130B is supplied to the wafer placement surface 104B to form the heat transfer layer D. １ It can function as at least a part of a heat transfer layer forming section configured to form a heat transfer layer D thereon.

[0098] Furthermore, in this example, for example, when the wafer W is supported on the wafer support table 101B, the wafer placement surface 104B １ A heat transfer medium is supplied to the wafer placement surface 104B. １ A deformable heat transfer layer D is formed thereon, which is made of at least one of a liquid layer and a solid layer.

[0099] Specifically, for example, with the wafer W supported on the wafer support table 101B, a heat transfer medium generating gas is supplied from the gas supply unit 130B to the flow path 310 of the wafer support table 101B. The heat transfer medium generating gas supplied to the flow path 310 is cooled in the flow path 310 and becomes a heat transfer medium composed of at least one of a liquid medium and a solid medium having fluidity. Then, this heat transfer medium flows through the supply port 300 to the wafer mounting surface 104B by, for example, capillary action. １ The wafer placement surface 104B １ After a predetermined amount of heat transfer medium is supplied to the electrostatic chuck 104B, a DC voltage is applied to the electrode 109 of the electrostatic chuck 104B. As a result, the wafer W is electrostatically attracted to the electrostatic chuck 104B by electrostatic force. At the same time, the heat transfer medium sandwiched between the wafer W and the electrostatic chuck 104B is attracted to the wafer mounting surface 104B. １ The heat transfer layer D is formed along the

[0100] <Variations in the supply form of heat transfer medium> In the above examples, the heat transfer medium generating gas is supplied to the wafer support table 101B from the outside and converted into a heat transfer medium within the wafer support table 101B, but the heat transfer medium may also be supplied directly to the wafer support table 101B from the outside.

[0101] In the above example, the wafer support surface 104B of the heat transfer medium in the wafer support table 101B １ Instead of this, the supply pressure of the heat transfer medium generating gas to the wafer support table 101B from the outside or the supply pressure of the heat transfer medium to the wafer support table 101B is used to supply the heat transfer medium to the wafer support surface 104B of the heat transfer medium in the wafer support table 101B. １ The supply to

[0102] <Modifications of Electrostatic Chuck Electrodes and Heat Transfer Medium Spreading Method> Figures 18 and 19 are plan and cross-sectional views, respectively, that schematically illustrate modifications of the electrodes of the electrostatic chuck. In the above examples, the electrostatic chuck 104 is provided with a single electrode 109 that straddles the central and outer periphery of the electrostatic chuck 104. Alternatively, as in the electrostatic chuck 104C of Figures 18 and 19, multiple (three in the illustrated example) electrodes 109C that are annular in plan view may be arranged concentrically with respect to the center of the electrostatic chuck 104C. Note that, hereinafter, the three electrodes 109C in the figures may be referred to as electrode 109C1, electrode 109C2, and electrode 109C3, in that order from the center of the electrostatic chuck 104C.

[0103] Among the plurality of electrodes 109C, the electrode 109C provided in the center of the electrostatic chuck 104C is more sensitive to the wafer placement surface 104B than the electrodes 109C provided in the outer periphery of the electrostatic chuck 104C. １ In the example shown in the figure, the electrode 109C1 is located on the wafer placement surface 104B. １ The distance to the wafer mounting surface 104B is small, while the electrodes 109C2 and 109C3 are １ The distance to the electrode 109C is short. In the illustrated example, a common DC power supply (not shown) is provided for the three electrodes 109C, and switches 320 and 321 are provided to switch the destination of the voltage from the DC power supply. When switch 320 is turned OFF, the voltage from the DC power supply is applied only to electrode 109C1. When switch 320 is turned ON and switch 321 is turned OFF, the voltage from the DC power supply is applied to electrodes 109C1 and 109C2. When both switches 320 and 321 are turned ON, the voltage from the DC power supply is applied to electrodes 109C1, 109C2, and 109C3.

[0104] From the electrode 109C to the wafer placement surface 104B １ When the distance to the electrode 109C is smaller at the center of the electrostatic chuck 104 than at the outer periphery, a voltage is first applied from a DC power supply only to the electrode 109C provided at the center of the electrostatic chuck 104. As a result, the center of the wafer W is attracted to the center of the electrostatic chuck 104 by a large electrostatic force, and the wafer W is attracted to the wafer mounting surface 104B.１ The heat transfer medium supplied to the center of the wafer placement surface 104B １ Then, a voltage is applied from the DC power supply to the electrode 109C provided on the outer periphery of the electrostatic chuck 104. As a result, the wafer mounting surface 104B １ The heat transfer medium that has spread to the outer periphery of the wafer mounting surface 104B is transferred by a small electrostatic force. １ Since the heat transfer medium spreads in this way, the heat transfer medium is １ It is possible to prevent the wafer from being stopped at the center of the wafer placement surface 104B. １ The heat transfer medium that spreads outward vaporizes.

[0105] In the case of the electrostatic chuck 104C of Figures 18 and 19, when forming the heat transfer layer D, the electrodes 109C to which the voltage is applied from the DC power supply may be increased in number in sequence from the center of the electrostatic chuck 104C.

[0106] From the electrode 109C to the wafer placement surface 104B １ When the distance to the wafer mounting surface 104B is smaller at the center than at the periphery of the electrostatic chuck 104, the heat transfer layer D may be formed as follows. １ In a state where the heat transfer medium is present only in the center of the wafer placement surface 104B, a voltage may be applied to all the electrodes 109C simultaneously. １ and the wafer W, and the large electrostatic force between the center of the wafer W and the wafer mounting surface 104B １ A small electrostatic force may be simultaneously applied between the outer periphery of the wafer W and the wafer mounting surface 104B. １ The heat transfer medium supplied to the center of the wafer placement surface 104B is transferred by a large electrostatic force. １ and the small electrostatic force causes the wafer mounting surface 104B １ It spreads outwards.

[0107] In addition, when a plurality of electrodes 109C having a circular shape in a plan view are arranged concentrically with respect to the center of the electrostatic chuck C, the wafer mounting surface 104B １The distances to the electrodes 109C may be equal between the electrodes 109C, and each electrode 109C may be individually connected to a DC power supply. In this configuration, a high voltage is first applied only to the electrode 109C provided at the center of the electrostatic chuck 104. As a result, the center of the wafer W is attracted to the center of the electrostatic chuck 104 by a large electrostatic force, and the wafer W is attracted to the wafer mounting surface 104B. １ The heat transfer medium supplied to the center of the wafer placement surface 104B １ Then, a low voltage is applied to the electrode 109C provided on the outer periphery of the electrostatic chuck 104. As a result, the wafer mounting surface 104B １ The heat transfer medium that has spread to the outer periphery of the wafer mounting surface 104B is transferred by a small electrostatic force. １ The wafer mounting surface 104B extends outward. １ In a configuration in which the distances to the wafer mounting surface 104B are equal between the electrodes 109C and a DC power supply is individually connected to each electrode 109C, the following may be performed. １ From a state in which the heat transfer medium is present only in the center of the electrostatic chuck 104, both a strong voltage may be applied to the electrode 109C provided in the center of the electrostatic chuck 104 and a low voltage may be applied to the electrode 109C provided in the outer periphery of the electrostatic chuck 104.

[0108] 20 and 21 are cross-sectional views each showing a modified example of the electrode of the electrostatic chuck. Fig. 22 is a plan view showing a modified example of the electrode of the electrostatic chuck. The electrostatic chuck 104D shown in Fig. 20 is provided with a single electrode 109 extending across the central and outer periphery of the electrostatic chuck 104D. In addition, the electrostatic chuck 104D has a wafer mounting surface 104D. １ The electrostatic chuck 104D has a concave surface that is recessed downward, and the electrode 109 is formed in a horizontal plate shape. Therefore, the dielectric layer that constitutes the electrostatic chuck 104D is thinner at the center of the electrostatic chuck 104D than at the outer periphery of the electrostatic chuck 104D. In the electrostatic chuck 104D, when a voltage is applied to the electrode 109, the wafer mounting surface 104D １ and the wafer W, and the large electrostatic force between the center of the wafer W and the wafer mounting surface 104D １A small electrostatic force acts simultaneously between the outer periphery of the wafer W and the wafer W. Therefore, in the electrostatic chuck 104D, when a voltage is applied to the electrode 109, the wafer mounting surface 104B １ The heat transfer medium supplied to the center of the wafer placement surface 104B is transferred by a large electrostatic force. １ and the small electrostatic force causes the wafer mounting surface 104B １ It spreads outwards.

[0109] 20, the electrostatic chuck 104E of FIG. 21 is also provided with a single electrode 109E extending across the central portion and the outer periphery of the electrostatic chuck 104E. However, unlike the electrostatic chuck 104D, the electrostatic chuck 104E has a wafer mounting surface 104B. １ is formed on a horizontal surface, and the cross-sectional shape of the electrode 109E is the same as that of the wafer placement surface 104B １ The electrode 109E is formed in a triangular shape that protrudes toward the center of the electrostatic chuck 104E. As a result, the dielectric layer that constitutes the electrostatic chuck 104E is thinner at the center of the electrostatic chuck 104E than at the outer periphery of the electrostatic chuck 104E. In the electrostatic chuck 104E, when a voltage is applied to the electrode 109E, the wafer mounting surface 104B １ and the wafer W, and the large electrostatic force between the center of the wafer W and the wafer mounting surface 104B １ A small electrostatic force acts simultaneously between the outer periphery of the wafer W and the wafer W. Therefore, in the electrostatic chuck 104E, when a voltage is applied to the electrode 109E, the wafer mounting surface 104B １ The heat transfer medium supplied to the center of the wafer placement surface 104B is transferred by a large electrostatic force. １ and the small electrostatic force causes the wafer mounting surface 104B １ The cross-sectional shape of the electrode 109E extends outward from the wafer placement surface 104B. １ The shape does not have to be triangular as long as it protrudes toward the center.

[0110] 20, the electrostatic chuck 104F of FIG. 22 is also provided with a single electrode 109F that straddles the central portion and the outer periphery of the electrostatic chuck 104E. However, unlike the electrostatic chuck 104F, the electrostatic chuck 104F has a wafer mounting surface 104B. １ is formed on a horizontal surface, and the density of the electrode 109F is higher in the center of the electrostatic chuck 104F than in the outer periphery of the electrostatic chuck 104F. Therefore, in the electrostatic chuck 104F, when a voltage is applied to the electrode 109F, the wafer mounting surface 104B １ and the wafer W, and the large electrostatic force between the center of the wafer W and the wafer mounting surface 104B １ At the same time, a small electrostatic force acts between the outer periphery of the wafer W and the wafer W. Therefore, in the electrostatic chuck 104F, when a voltage is applied to the electrode 109F, the wafer mounting surface 104B １ The heat transfer medium supplied to the center of the wafer placement surface 104B is transferred by a large electrostatic force. １ and the small electrostatic force causes the wafer mounting surface 104B １ The shape of the electrode 109F in plan view is not limited to the shape of FIG. 22 as long as the density of the electrode 109F is higher at the outer periphery of the electrostatic chuck 104F than at the center of the electrostatic chuck 104F.

[0111] In the case where a single electrode is provided across the central and outer periphery of the electrostatic chuck and the wafer mounting surface is formed as a horizontal plane, the dielectric constant of the electrostatic chuck may vary within the plane, with the dielectric constant being higher in the central portion of the electrostatic chuck than in the outer periphery. In this electrostatic chuck, when a voltage is applied to the electrode, a large electrostatic force acts between the central portion of the wafer mounting surface and the wafer W, and a small electrostatic force acts between the outer periphery of the wafer mounting surface and the wafer W, simultaneously.

[0112] Methods for varying the dielectric constant within the surface of an electrostatic chuck include, for example, using different types of dielectric materials as constituent materials in the central portion and the outer periphery of the electrostatic chuck, and varying the concentration of the dielectric material in the constituent materials of the electrostatic chuck within the surface of the electrostatic chuck.

[0113] <Wafer placement surface 104 １Example of Upper Heat Transfer Layer D> FIG. 23 shows the wafer placement surface 104 １ 23 is a diagram showing an example of the upper heat transfer layer D. Note that the flow path 108 is omitted in FIG. 23. The heat transfer layer D is, for example, １ the wafer placement surface 104 including the central and peripheral regions of １ However, the wafer mounting surface 104 １ For example, when it is necessary to actively absorb or heat the peripheral portion of the wafer W, the heat transfer layer D may be formed only in a partial area of ​​the wafer mounting surface 104 facing the peripheral portion of the wafer W, as shown in FIG. １ Alternatively, for example, when the central portion of the wafer W needs to be actively heated or absorbed, the heat transfer layer D may be formed only in the peripheral region of the wafer mounting surface 104 facing the central portion of the wafer W. １ The heat transfer layer D may be formed only in the central region of the heat transfer layer D.

[0114] wafer placement surface 104 １ For example, a method for forming the heat transfer layer D only on a part of the wafer mounting surface 104 is as follows. １ By making the wafer-mounting surface 104 have both a lipophilic portion and an oil-repellent portion, the heat-transfer layer D can be formed only on either the lipophilic portion or the oil-repellent portion. １ For example, the method for forming the wafer mounting surface 104 is as follows. １ This is a method of applying an oil-philic treatment to a portion of the surface and an oil-repellent treatment to the other portion. The oil-philic treatment is, for example, a treatment of coating with a substance having a hydrocarbon group or a treatment of forming a predetermined nano-order shape on the surface. The oil-repellent treatment is a treatment of coating with silicone resin, fluorine-based material, hydrophilic inorganic substance, etc.

[0115] In addition, when the raw material of the heat transfer layer D is the above-mentioned heat transfer medium constituted by a liquid medium or the like, for example, the wafer mounting surface 104 １ By forming grooves only in a partial region such as the peripheral region, the heat transfer layer D can be formed only in that partial region.

[0116] As described above, the wafer placement surface 104 １ When the heat transfer layer D is formed only in a partial area of ​​the wafer mounting surface 104 as shown in FIG. １ The wafer support table 101 may be provided with a supply path 190 for supplying a heat transfer gas such as He gas to a portion between the wafer W and a portion where the heat transfer layer D is not formed. This allows the wafer support table 101 to improve the temperature control capability of the wafer W by the wafer mounting surface 104. １ In other words, the temperature control capability of the wafer W by the wafer support table 101 can be distributed.

[0117] This is not the only way to provide a distribution in the temperature control capability of the wafer W. For example, when the raw material of the heat transfer layer D is the aforementioned heat transfer medium constituted by a liquid medium or the like, grooves may be formed in each region and a heat transfer medium with a different thermal conductivity may be supplied to each region, thereby providing a distribution in the temperature control capability of the wafer W by the wafer support table 101.

[0118] In addition, the heat transfer layer D has thick and thin portions on the wafer mounting surface 104. １ By providing the wafer support table 101 with the above-mentioned arrangement, the temperature control capability of the wafer W by the wafer support table 101 may be distributed.

[0119] Furthermore, the wafer placement surface 104 １ The wafer mounting surface 104 has a wide surface area and a narrow surface area. １ By forming the heat transfer layer D on the entire surface, the temperature control capability of the wafer W by the wafer support table 101 (specifically, the wafer mounting surface 104 １ and the temperature control ability of the wafer W via the heat transfer layer D) can be distributed. １ By performing a surface roughening process on the wafer mounting surface 104, １ It is possible to form both large and small surface area portions.

[0120] (Other Modifications) In the above examples, the target of temperature adjustment via the wafer support pedestal 101 and the deformable heat transfer layer D was the wafer W. However, instead of or in addition to this, the edge ring E may be the target. That is, in the present disclosure, the workpiece whose temperature is to be adjusted is at least one of the wafer W and the edge ring E. Furthermore, the above-described methods of removing the heat transfer layer formed on each part may be combined. For example, when removing a heat transfer layer formed on a surface other than the wafer mounting surface, two or more of the methods of reducing the pressure inside the processing chamber 100, using plasma, and irradiating light may be combined.

[0121] In the above example, the central portion of the electrostatic chuck 104 on which the wafer W is placed is formed to have a diameter smaller than the diameter of the wafer W. However, it may be formed to have a diameter larger than the diameter of the wafer W. Also, in the above example, the central portion of the electrostatic chuck 104, which has a diameter smaller than the diameter of the wafer W, is formed to be higher than the upper surface of the peripheral portion, but they may be at the same height. FIG. 24 is a diagram showing an example in which the central portion of the electrostatic chuck 104 is formed to have a diameter larger than the diameter of the wafer W. Note that in the example shown in FIG. 24, the central portion of the electrostatic chuck 104, which has a diameter larger than the diameter of the wafer W, and the peripheral portion are formed to be at the same height. However, the upper surface of the central portion may be formed to be higher than the upper surface of the peripheral portion, as shown in FIG. 1.

[0122] In the example shown in FIG. 24, the central portion of the electrostatic chuck 104 (i.e., the wafer mounting surface 104 １ ) is formed to have a diameter larger than the diameter of the wafer W. Therefore, the peripheral edge of the wafer W does not protrude from the center of the electrostatic chuck 104, and is connected to the wafer mounting surface 104 via the heat transfer layer D. １ Therefore, the temperature uniformity of the wafer W can be improved. １ Since the heat transfer layer D is also formed in the end area of ​​the wafer support surface 104, the electrostatic chuck 104 is not exposed to the processing space 100s even in the end area where the wafer W is not placed. １ In the end region, the electrostatic chuck 104 can be protected from the plasma.

[0123] 25, a tray T on which a wafer W is placed and a heat transfer layer D is formed between the wafer W and the tray T is placed on the wafer placement surface 104. １ In this example, under the control of the control unit 200, the tray T is lifted by the lifter 107 onto the wafer placement surface 104 of the wafer support table 101. １ By placing the wafer on the wafer placement surface 104 １ In this embodiment, therefore, a heat transfer layer D is formed on the wafer W (or the tray T on which the wafer W is placed) via the tray T. Therefore, in this embodiment, the controller 200 and the lifter 107 are configured to raise and lower the wafer W (or the tray T on which the wafer W is placed) by controlling the wafer placement surface 104 １ It can function as a part of the heat transfer layer forming section that forms the heat transfer layer D thereon.

[0124] The tray T is held by an electrostatic chuck 104 by electrostatic attraction. A heat transfer layer D is formed in the center of the tray T, and a wafer W is placed on the heat transfer layer D. An edge ring E is placed on the periphery of the tray T, and by loading and unloading the tray, not only the wafer W but also the edge ring E can be replaced. Note that a heat transfer layer D may also be formed between the edge ring E and the tray T.

[0125] 25, the peripheral portion of the wafer W is also placed on the tray T via the heat transfer layer D. This improves the temperature uniformity of the wafer W. The heat transfer layer D is also formed on the upper surface of the tray T on which the wafer W and the edge ring E are not placed. Therefore, the upper surface of the tray T is not exposed to the processing space 100s even in the area on which the wafer W or the edge ring E is not placed, and the tray T can be protected from plasma.

[0126] A heat transfer layer D may also be formed between the tray T and the electrostatic chuck 104. Alternatively, only the wafer W may be placed on the tray T, and the edge ring E may be placed on the electrostatic chuck 104. In this case, the mounting surface of the edge ring E on the periphery of the electrostatic chuck 104 may be formed at the same height as the center of the electrostatic chuck 104 (the mounting surface of the tray T) as shown in FIG. 24 , or may be formed lower than the center (the mounting surface of the tray T) as shown in FIG. 1 .

[0127] In the above example, plasma etching was performed as the plasma processing, but the technology disclosed herein can also be applied to cases where processing other than etching (for example, film formation processing) is performed as the plasma processing.

[0128] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. For example, the components of the above-described embodiments may be arbitrarily combined. Such an arbitrary combination naturally provides the functions and effects of each of the components involved in the combination, and also provides other functions and effects that are apparent to those skilled in the art from the description of this specification.

[0129] Furthermore, the effects described herein are merely descriptive or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that are apparent to those skilled in the art from the description of this specification, in addition to or in place of the above-described effects.

[0130] The following configuration examples also fall within the technical scope of the present disclosure. (1) A plasma processing apparatus comprising: a processing vessel configured to be depressurized; a support section provided within the processing vessel and supporting a workpiece; a heat-transfer layer forming section configured to form a deformable heat-transfer layer for the workpiece, the heat-transfer layer being composed of at least one of a liquid layer and a solid layer on a mounting surface of the support section on which the workpiece is mounted; an exhaust line for exhausting air from a processing space within the processing vessel; and a bypass line that bypasses the exhaust line, the bypass line having a trap interposed therein for recovering gaseous gas contained in the exhaust from the processing space. (2) The plasma processing apparatus described in (1), wherein the heat-transfer layer forming section supplies a source gas serving as a source material for the heat-transfer layer to the processing space within the processing vessel; and the gaseous heat-transfer layer recovered in the trap is the source gas. (3) The plasma processing apparatus described in (2), wherein the trap also recovers a vaporized product of the heat-transfer layer formed on the mounting surface as the gaseous heat-transfer layer. (4) The plasma processing apparatus according to (2) or (3), further comprising a return line for returning the source gas of the heat transfer layer recovered in the trap to the heat transfer layer forming section. (5) The plasma processing apparatus according to any one of (2) to (4), wherein the mounting surface has a lipophilic portion and a lipophobic portion, and the heat transfer layer is formed on only one of them. (6) The plasma processing apparatus according to (5), wherein the support portion has a supply path for supplying a heat transfer gas between the portion of the mounting surface on which the heat transfer layer is not formed and the workpiece. (7) The plasma processing apparatus according to any one of (1) to (6), wherein the mounting surface has a portion with a large surface area and a portion with a small surface area. (8) The plasma processing apparatus according to any one of (1) to (7), wherein the mounting surface is roughened.(9) The plasma processing apparatus according to any one of (2) to (6), further comprising an inert gas supply unit that supplies an inert gas to the processing space in the processing vessel, and a control unit, wherein the control unit executes the steps of supplying both the source gas and the inert gas to the processing space to form the heat transfer layer in a state where the processing space is not being exhausted through the exhaust line but is being exhausted through the bypass line. (10) The plasma processing apparatus according to any one of (2) to (6), further comprising a control unit, wherein the control unit executes the steps of supplying the source gas to the processing space in a state where the processing space is not being exhausted through the exhaust line but is being exhausted through the bypass line, and thereafter continuing the supply of the source gas to the processing space in a state where the processing space is not being exhausted, including through the bypass line, to form the heat transfer layer. (11) The plasma processing apparatus according to (10), further comprising an inert gas supply unit that supplies an inert gas to the processing space in the processing vessel, wherein the step of forming the heat transfer layer also supplies the inert gas to the processing space. (12) The plasma processing apparatus according to any one of (2) to (6), further comprising an inert gas supply unit that supplies an inert gas to the processing space in the processing vessel, and a control unit, wherein the plasma processing apparatus performs the steps of supplying the source gas to the processing space in a state in which the processing space is not evacuated through the exhaust line but is evacuated through the bypass line, and thereafter supplying the inert gas instead of the source gas to the processing space in a state in which the processing space is evacuated through the bypass line but is evacuated through the exhaust line, thereby forming the heat transfer layer. (13) The plasma processing apparatus according to any one of (1) to (12), wherein a first exhaust pump and a second exhaust pump are provided in the exhaust line in this order from the upstream side, and a downstream end of the bypass line is connected to the exhaust line between the first exhaust pump and the second exhaust pump. (14) The plasma processing apparatus according to (13), wherein a pressure adjustment valve is connected to the bypass line downstream of the trap.(15) The plasma processing apparatus according to (14), wherein an on-off valve is provided in the bypass line upstream of the trap and downstream of the pressure adjustment valve, and an on-off valve is provided between a portion of the exhaust line connected to the downstream end of the bypass line and the first exhaust pump. (16) A processing method for performing plasma processing on a substrate, comprising: (A) forming a deformable heat transfer layer for a workpiece, the heat transfer layer being composed of at least one of a liquid layer and a solid layer, on a mounting surface of a support part in a processing vessel configured to be able to reduce pressure; (B) mounting a substrate on the heat transfer layer formed on the mounting surface of the support part; (C) performing plasma processing on the substrate; (D) separating the substrate from the heat transfer layer and removing the heat transfer layer formed on the mounting surface; and (E) recovering gaseous heat transfer layer contained in exhaust from the processing space with a trap provided in a bypass line that bypasses an exhaust line that exhausts the processing space in the processing vessel. (17) The processing method according to (16), further comprising, before the step (A), the steps of closing a valve provided in the exhaust line, opening a valve provided in the bypass line to evacuate the processing space in the processing vessel through the bypass line, and supplying a source gas serving as a source of the heat transfer layer to the processing space. (18) The processing method according to (16) or (17), further comprising, between the steps (B) and (C), the steps of closing a valve provided in the bypass line and opening a valve provided in the exhaust line to evacuate the processing space in the processing vessel through the exhaust line. (19) The processing method according to any one of (16) to (18), wherein the step (A) includes the steps of increasing the pressure in the processing vessel or decreasing the temperature of the placement surface.

[0131] REFERENCE SIGNS LIST 1 Plasma processing apparatus 100 Plasma processing chamber 100s Plasma processing space 101 Wafer support 130 Gas supply unit 160 Exhaust line 170 Bypass line 171 Trap 104 １ Wafer placement surface 104 ２Upper surface of the peripheral portion of the electrostatic chuck D Heat transfer layer E Edge ring W Wafer

Claims

1. A plasma processing apparatus comprising: a processing vessel configured to be depressurized; a support section provided within the processing vessel for supporting a workpiece; a heat transfer layer forming section that forms a deformable heat transfer layer for the workpiece, the heat transfer layer being composed of at least one of a liquid layer and a solid layer, on a mounting surface of the support section on which the workpiece is placed; an exhaust line that exhausts air from a processing space within the processing vessel; and a bypass line that bypasses the exhaust line, wherein the bypass line has a trap interposed therein for recovering gaseous heat transfer layer contained in the exhaust from the processing space.

2. The plasma processing apparatus according to claim 1, wherein the heat transfer layer forming unit supplies a source gas that is a raw material for the heat transfer layer to the processing space in the processing vessel, and the gaseous heat transfer layer recovered in the trap is the source gas.

3. The plasma processing apparatus according to claim 2, wherein the trap also collects vaporized material of the heat transfer layer formed on the mounting surface as the gaseous heat transfer layer.

4. The plasma processing apparatus according to claim 2, further comprising a return line for returning the source gas of the heat transfer layer recovered in the trap to the heat transfer layer forming section.

5. The plasma processing apparatus according to claim 2, wherein the mounting surface has a lipophilic portion and an lipophobic portion, and the heat transfer layer is formed on only one of the portions.

6. The plasma processing apparatus according to claim 5, wherein the support portion has a supply path for supplying a heat transfer gas between the portion of the mounting surface on which the heat transfer layer is not formed and the workpiece.

7. The plasma processing apparatus according to claim 1, wherein the mounting surface has a portion with a large surface area and a portion with a small surface area.

8. The plasma processing apparatus according to any one of claims 1 to 7, wherein the mounting surface is roughened.

9. A plasma processing apparatus according to any one of claims 2 to 6, further comprising: an inert gas supply unit that supplies an inert gas to the processing space in the processing vessel; and a control unit, wherein the control unit executes a step of supplying both the source gas and the inert gas to the processing space to form the heat transfer layer in a state in which the processing space is not being exhausted via the exhaust line but is being exhausted via the bypass line.

10. A plasma processing apparatus according to any one of claims 2 to 6, further comprising a control unit, wherein the control unit executes the steps of: supplying the raw material gas to the processing space while exhausting the processing space through the bypass line without exhausting the processing space through the exhaust line; and thereafter continuing to supply the raw material gas to the processing space while exhausting the processing space, including exhausting through the bypass line, is not being performed, thereby forming the heat transfer layer.

11. The plasma processing apparatus according to claim 10, further comprising an inert gas supply unit that supplies an inert gas to the processing space in the processing vessel, wherein the step of forming the heat transfer layer also supplies the inert gas to the processing space.

12. A plasma processing apparatus according to any one of claims 2 to 6, further comprising an inert gas supply unit that supplies an inert gas to the processing space in the processing vessel; and a control unit, and performs the steps of: supplying the raw material gas to the processing space in a state in which the processing space is not evacuated through the exhaust line but is evacuated through the bypass line; and thereafter supplying the inert gas instead of the raw material gas to the processing space in a state in which the processing space is not evacuated through the exhaust line but is evacuated through the bypass line, thereby forming the heat transfer layer.

13. A plasma processing apparatus according to any one of claims 1 to 7, wherein a first exhaust pump and a second exhaust pump are interposed in the exhaust line in this order from the upstream side, and the downstream end of the bypass line is connected between the first exhaust pump and the second exhaust pump in the exhaust line.

14. The plasma processing apparatus according to claim 13, wherein a pressure regulating valve is connected to the bypass line downstream of the trap.

15. A plasma processing apparatus as described in claim 14, wherein an on-off valve is provided in the bypass line upstream of the trap and downstream of the pressure adjustment valve, and an on-off valve is provided between the portion of the exhaust line to which the downstream end of the bypass line is connected and the first exhaust pump.

16. A processing method for performing plasma processing on a substrate, comprising: (A) forming a deformable heat transfer layer for a workpiece, the heat transfer layer consisting of at least one of a liquid layer and a solid layer, on a mounting surface of a support part in a processing vessel configured to be depressurized; (B) placing a substrate on the heat transfer layer formed on the mounting surface of the support part; (C) performing plasma processing on the substrate; (D) separating the substrate from the heat transfer layer and removing the heat transfer layer formed on the mounting surface; and (E) recovering the gaseous heat transfer layer contained in the exhaust from the processing space with a trap provided in a bypass line that bypasses an exhaust line that exhausts the processing space in the processing vessel.

17. The processing method according to claim 16, further comprising, before step (A), the steps of: closing a valve provided in the exhaust line; opening a valve provided in the bypass line to exhaust the processing space in the processing vessel through the bypass line; and supplying a raw material gas that serves as a raw material for the heat transfer layer to the processing space.

18. The processing method according to claim 17, further comprising, between step (B) and step (C), the steps of: closing a valve provided in the bypass line; and opening a valve provided in the exhaust line to exhaust the processing space in the processing vessel through the exhaust line.

19. The processing method according to claim 16, wherein the step (A) includes a step of increasing the pressure in the processing vessel or a step of decreasing the temperature of the placement surface.

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