Substrate processing apparatus

Abstract

This substrate processing apparatus includes: a substrate support part that supports a substrate; a plurality of lift pins that are provided in the substrate support part and can raise and lower the substrate relative to the substrate support part; and a heat transfer gas supply unit that supplies a heat transfer gas to the substrate supported by the substrate support part. Each among the plurality of lift pins is formed in a cylindrical shape having a hollow section extending in the axial direction and an opening communicating with the hollow section. The heat transfer gas supply unit supplies the heat transfer gas to the rear surface of the substrate via the hollow section and the opening. As a result of this configuration, the substrate processing apparatus can stably supply the heat transfer gas to the rear surface of the substrate while suppressing abnormal discharge.

Description

Substrate processing apparatus

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

[0002] Patent Document 1 discloses a plasma processing apparatus that performs plasma processing on a substrate placed on a substrate support (mounting table) in a plasma processing chamber. This substrate support includes a heat transfer gas supply path that supplies heat transfer gas to the back surface of the substrate in order to adjust the temperature of the substrate. Further, the substrate support enables heat transfer gas to be supplied also from the pin insertion passage by communicating the pin insertion passage of the lifter pin with the heat transfer gas supply path.

[0003] Japanese Unexamined Patent Application Publication No. 2021-108334

[0004] The present disclosure provides a technique capable of stably supplying heat transfer gas to the back surface of a substrate while reducing the number of holes for supplying heat transfer gas in the substrate support.

[0005] According to one aspect of the present disclosure, there is provided a substrate processing apparatus including: a substrate support that supports a substrate; a plurality of lift pins provided on the substrate support and capable of moving the substrate up and down relative to the substrate support; and a heat transfer gas supply unit that supplies heat transfer gas to the substrate supported by the substrate support, wherein the plurality of lift pins are formed in a cylindrical shape having an axially extending hollow portion and an opening communicating with the hollow portion, and the heat transfer gas supply unit supplies the heat transfer gas to the back surface of the substrate through the hollow portion and the opening.

[0006] According to one aspect, heat transfer gas can be stably supplied to the back surface of the substrate while reducing the number of holes for supplying heat transfer gas in the substrate support.

[0007] This figure illustrates an example configuration of a capacitively coupled plasma processing apparatus. It is a side cross-sectional view showing a part of the lifter section and heat transfer gas supply section provided in the substrate support section according to the first embodiment. Figure 3(A) is a plan view showing an example arrangement of each lift pin and each lift pin housing section. Figure 3(B) is a perspective view showing the upper end of the lift pin. This flowchart shows a plasma processing method for a plasma processing apparatus that performs plasma processing while supplying heat transfer gas. This figure shows a comparison between the substrate support section according to the first embodiment and a conventional substrate support section. Figure 6(A) is a cross-sectional view showing the substrate support section according to the second embodiment. Figure 6(B) is a perspective view showing the upper part of the lift pin of the substrate support section according to the second embodiment.

[0008] The following describes embodiments for implementing this disclosure with reference to the drawings. In each drawing, the same reference numerals are used for identical components, and redundant explanations may be omitted.

[0009] The following describes an example of a plasma processing system configuration. Figure 1 is a diagram illustrating an example of a capacitively coupled plasma processing system configuration.

[0010] The plasma processing system includes a capacitively coupled plasma processing apparatus 1, which is a substrate processing apparatus, and a control unit 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply system 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is configured to introduce at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is located inside the plasma processing chamber 10. The shower head 13 is located above the substrate support unit 11. In one embodiment, the shower head 13 constitutes at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the shower head 13, the side walls 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s, and at least one gas outlet for discharging gas from the plasma processing space. The plasma processing chamber 10 is grounded. The shower head 13 and the substrate support portion 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0011] The substrate support portion 11 includes a main body portion 111 and a ring assembly 112. The main body portion 111 has a substrate support surface 111a for supporting the substrate W and a ring support surface 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The ring support surface 111b of the main body portion 111 surrounds the substrate support surface 111a of the main body portion 111 in a plan view. The substrate W is placed on the substrate support surface 111a of the main body portion 111, and the ring assembly 112 is placed on the ring support surface 111b of the main body portion 111 so as to surround the substrate W on the substrate support surface 111a of the main body portion 111. Therefore, the substrate support surface 111a is the central region of the substrate support portion 11, and the ring support surface 111b is a tubular region that encircles the central region.

[0012] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 is constructed by stacking a first block 14 and a second block 15 vertically upward. The first block 14 is supported by a cylindrical insulating member 17. The first block 14 is made of an insulating material such as ceramic. On the other hand, the second block 15 is made of a conductive material. The second block 15 can function as a lower electrode. Note that both the first block 14 and the second block 15 of the base 1110 may be made of a conductive material.

[0013] The electrostatic chuck 1111 is placed on a base 1110 (second block 15). The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic chuck electrode 1111b placed within the ceramic member 1111a. The electrostatic chuck electrode 1111b is also called a clamping electrode. In one embodiment, the electrostatic chuck electrode 1111b is electrically connected or coupled to a chuck power supply. The chuck power supply may be a DC power supply or an AC power supply. The ceramic member 1111a has a substrate support surface 111a. In one embodiment, the ceramic member 1111a also has a ring support surface 111b. Other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may also have a ring support surface 111b. In this case, the ring assembly 112 may be placed on an annular electrostatic chuck or an annular insulating member, or it may be placed on both the electrostatic chuck 1111 and the annular insulating member. Also, at least one bias electrode, which is electrically connected or coupled to a power supply 31 and / or power supply 32 described later, may be placed inside the ceramic member 1111a. In this case, at least one bias electrode functions as a lower electrode. Also, the conductive member of the base 1110 and the bias electrode inside the ceramic member 1111a may function as multiple lower electrodes. In one embodiment, the first voltage generation unit 32a, which functions as a voltage pulse generation unit described later, is electrically connected or coupled to the bias electrode inside the ceramic member 1111a, and the first RF generation unit 31a, described later, is electrically connected or coupled to the conductive member of the base 1110. Also, the electrostatic chuck electrode 1111b may function as a lower electrode. Therefore, the substrate support unit 11 includes at least one lower electrode.

[0014] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one covering ring. The edge rings are formed of a conductive or insulating material, and the covering rings are formed of an insulating material.

[0015] The substrate support section 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature control module may include a heater, a heat transfer medium, a flow path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path 1110a. In one embodiment, the flow path 1110a is formed within the base 1110, and one or more heaters are arranged within the ceramic member 1111a of the electrostatic chuck 1111. The substrate support section 11 also includes a heat transfer gas supply section 60 (see Figure 2) configured to supply heat transfer gas to the gap between the back surface of the substrate W and the substrate support surface 111a. This heat transfer gas supply section 60 will be described in detail later.

[0016] The showerhead 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and a plurality of gas inlet ports 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s through the plurality of gas inlet ports 13c. The showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas introduction unit may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 10a.

[0017] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one processing gas to the shower head 13 from a corresponding gas source 21 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may include one or more flow modulation devices that modulate or pulse the flow rate of at least one processing gas.

[0018] The power supply system 30 includes a power supply 31 that is electrically connected to or coupled to the plasma processing chamber 10. In one embodiment, the power supply 31 is electrically connected to or coupled to the plasma processing chamber 10 via at least one impedance matcher. The impedance matcher may be a mechanically controlled matcher or an electronically controlled matcher. The power supply 31 is configured to supply at least one RF (Radio Frequency) signal (RF power) to at least one lower electrode and / or at least one upper electrode. This generates plasma from at least one processing gas supplied to the plasma processing space 10s. Therefore, the power supply 31 can function as at least part of a plasma generation unit configured to generate plasma from one or more processing gases in the plasma processing chamber 10. In addition, by supplying a bias RF signal to at least one lower electrode, a bias potential is generated on the substrate W, and ionic components in the formed plasma can be drawn into the substrate W.

[0019] The power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is electrically connected or coupled to at least one lower electrode and / or at least one upper electrode and is configured to generate a source RF signal (source RF power) to generate plasma in the plasma processing space 10s. In one embodiment, the first RF generation unit 31a is electrically connected or coupled to at least one lower electrode and / or at least one upper electrode via at least one impedance matcher. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generation unit 31a may be configured to generate a plurality of source RF signals having different frequencies. One or more generated source RF signals are supplied to at least one lower electrode and / or at least one upper electrode.

[0020] The second RF generation unit 31b is electrically connected to or coupled to at least one lower electrode and is configured to generate a bias RF signal (bias RF power). In one embodiment, the second RF generation unit 31b is electrically connected to or coupled to at least one lower electrode via at least one impedance matcher. When the first RF generation unit 31a is electrically connected to or coupled to a lower electrode, the second RF generation unit 31b may be electrically connected to or coupled to the same lower electrode, or it may be electrically connected to or coupled to a different lower electrode. The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0021] The power supply system 30 may also include a power supply 32 that is electrically connected to or coupled to the plasma processing chamber 10. The power supply 32 includes a first voltage generation unit 32a and a second voltage generation unit 32b. In one embodiment, the first voltage generation unit 32a is electrically connected to or coupled to at least one lower electrode and is configured to generate a first voltage signal. The generated first voltage signal is applied to at least one lower electrode. In one embodiment, the second voltage generation unit 32b is electrically connected to or coupled to at least one upper electrode and is configured to generate a second voltage signal. The generated second voltage signal is applied to at least one upper electrode.

[0022] In various embodiments, the first and / or second voltage signals may be pulsed. In this case, the first voltage generation unit 32a and / or the second voltage generation unit 32b function as voltage pulse generation units configured to generate a sequence of voltage pulses. Thus, the sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. In one embodiment, the sequence of voltage pulses has a plurality of cycles, each cycle including a burst of voltage pulses in a first period and a constant reference voltage in a second period. That is, in the sequence of voltage pulses, the burst of voltage pulses is repeated. The absolute value of the voltage level of the voltage pulse is greater than the absolute value of the voltage level of the reference voltage. The voltage pulse may have an arbitrary waveform having a rectangle, trapezoid, triangle, or a combination thereof, and the arbitrary waveform may change over time. The voltage pulse may have positive polarity or negative polarity. The sequence of voltage pulses may also include one or more positive voltage pulses and one or more negative voltage pulses within one cycle. The first and second voltage generation units 32a and 32b may be provided in addition to the power supply 31, and the first voltage generation unit 32a may be provided in place of the second RF generation unit 31b.

[0023] The exhaust system 40 may be connected to, for example, a gas outlet 10e located at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure regulating valve regulates the pressure in the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0024] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various processes described herein. The control unit 2 may be configured to control the elements of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 is implemented, for example, by a computer 2a. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The functions realized by the processing unit 2a1 described herein may be implemented in a circuit or processing circuit, including a general-purpose processor, an application-specific processor, integrated circuits, ASICs (Application Specific Integrated Circuits), a CPU (Central Processing Unit), a conventional circuit, and / or a combination thereof, programmed to realize the described functions. The processor is considered to be a circuit or processing circuit, including transistors and other circuits. The processor may be a programmed processor that executes a program stored in the storage unit 2a2. This program may be pre-stored in the storage unit 2a2 or retrieved via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 and executed by the processing unit 2a1. The medium may be various storage media readable by the computer 2a, or it may be a communication line connected to the communication interface 2a3. The storage unit 2a2 may include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network).In this disclosure, circuits, units, and means are hardware programmed to perform or configured to perform the functions described. Such hardware may be any hardware described in this disclosure, or any hardware known to be programmed to perform or execute the functions described. If such hardware is a processor that is considered to be a type of circuit, such circuit, means, or unit is a combination of hardware and software used to constitute such hardware and / or processor.

[0025] <First Embodiment> Next, the lifter portion 50 and the heat transfer gas supply portion 60 of the substrate support portion 11 according to the first embodiment will be described with reference to Figure 2. Figure 2 is a side cross-sectional view showing a part of the lifter portion 50 and the heat transfer gas supply portion 60 provided on the substrate support portion 11. The plasma processing apparatus 1 according to the embodiment includes a lifter portion 50 that places a substrate W on the substrate support surface 111a of the substrate support portion 11 and also levitates the substrate W on the substrate support surface 111a.

[0026] The lifter section 50 comprises a plurality of lift pins 51 (for example, three), a lifting mechanism 52 for raising and lowering the lift pins 51, and a lift pin housing section 53 for housing each of the lift pins 51. Each lift pin 51 is housed in its respective lift pin housing section 53 and is supported by the lifting mechanism 52 at the lower end of the substrate support section 11 (first block 14). Each lift pin 51 extends linearly along the vertical direction. A gap is formed between the outer circumferential surface of each lift pin 51 and the inner circumferential surface of each lift pin housing section 53, allowing the lift pin 51 to be displaced vertically.

[0027] The material forming each lift pin 51 should be appropriately selected to be a material with high plasma resistance and / or high heat conductivity. For example, the material for the lift pin 51 may be aluminum alloy, silicon carbide, ceramic, or stainless steel.

[0028] The lifting mechanism 52 includes a drive source (motor, cylinder, etc.) and a drive transmission unit (not shown), and raises and lowers each lift pin 51 as a whole based on the control of the control unit 2. In Figure 2, an example is shown in which one lifting mechanism 52 is provided for one lift pin 51 (each of the multiple lift pins 51 is provided with its own lifting mechanism 52). However, the plasma processing apparatus 1 may also be configured to support and raise and lower multiple lift pins 51 as a whole with one lifting mechanism 52.

[0029] Figure 3(A) is a plan view showing an example of the arrangement of each lift pin 51 and each lift pin housing 53. Figure 3(B) is a perspective view showing the upper end of the lift pin 51. As shown in Figure 3(A), each lift pin 51 and each lift pin housing 53 are installed in the circumferential direction, separated by a predetermined radius from the center of the substrate support surface 111a. The three lift pins 51 and the three lift pin housings 53 are arranged at equal intervals (120°) from each other along the circumferential direction.

[0030] When receiving a substrate W, the lifter unit 50 raises each lift pin 51 to levitate the substrate W held by a fork (not shown), and after the fork retracts, lowers each lift pin 51 to place the substrate W on the substrate support surface 111a. Also, when transferring a substrate W, the lifter unit 50 raises each lift pin 51 to levitate the substrate W, and after the fork enters below the substrate W, lowers each lift pin 51 to place the substrate W on the fork.

[0031] Returning to Figure 2, the plasma processing apparatus 1 includes a heat transfer gas supply unit 60 that supplies heat transfer gas to the back side of the substrate W placed on the substrate support unit 11. Preferably, the heat transfer gas supplied by the heat transfer gas supply unit 60 is a gas with high thermal conductivity, such as helium (He) gas. In this type of plasma processing apparatus 1, unintended abnormal discharge may occur in the substrate support unit 11 that supplies the heat transfer gas during plasma processing. To reduce the location of such abnormal discharge, the plasma processing apparatus 1 according to the first embodiment is configured to supply the heat transfer gas using three lift pins 51, thereby minimizing the number of holes for supplying the heat transfer gas.

[0032] Therefore, each lift pin 51 in the first embodiment has a cylindrical shape that allows heat transfer gas to be supplied. Specifically, each lift pin 51 has a hollow portion 54 that extends in the axial direction and an opening 54o that communicates with the hollow portion 54. The hollow portion 54 penetrates each lift pin 51 from its tip to its base.

[0033] The hollow portion 54 of each lift pin 51 extends along the axial direction with a constant inner diameter. The inner diameter of the lift pin 51 surrounding the hollow portion 54 is preferably set in the range of, for example, 1 mm to 9 mm. On the other hand, the outer diameter of the lift pin 51 is preferably set in the range of, for example, 2 mm to 10 mm. Each lift pin 51 may have a step 512 at an intermediate position on its outer circumference where the outer diameter changes. The inner diameter of the lift pin 51 may also change in accordance with the step 512, etc. For example, by making the tip side smaller in diameter, the flow velocity of the heat transfer gas can be increased.

[0034] Each lift pin 51 has an opening 54o on one end face (upper end 511) that extends in a straight line (see also Figure 3(B)). Therefore, each lift pin 51 can discharge the heat transfer gas supplied through the hollow portion 54 to the vertically upward side. Alternatively, each lift pin 51 may be configured to have multiple openings 54o on its outer peripheral surface below the upper end 511, and to discharge the heat transfer gas laterally from the outer peripheral surface. This causes the heat transfer gas discharged from each opening 54o to spread out without concentrating and hitting a localized area on the back surface of the substrate W.

[0035] On the other hand, each lift pin housing 53 has an opening 53o in the bottom surface 111a2 between a plurality of ribs 111a1 that constitute the substrate support surface 111a. Each lift pin housing 53 discharges heat transfer gas from the opening 53o into grooves 111c formed between adjacent ribs 111a1. The heat transfer gas discharged into the grooves 111c moves circumferentially or radially along the shape of the grooves 111c to adjust the temperature of the substrate W.

[0036] The opening 54o at the upper end 511 of each lift pin 51 is positioned lower than the opening 53o of the lift pin housing 53 when each lift pin 51 is in the standby position during substrate processing. As a result, the heat transfer gas discharged from the opening 54o of each lift pin 51 is diffused as it moves through the opening 54o and groove 111c of the lift pin housing 53 and flows into the groove 111c.

[0037] Each lift pin 51 has a heat transfer gas supply path 61 connected to the base end of a heat transfer gas supply unit 60 that communicates with the hollow section 54. The heat transfer gas supply path 61 is connected to a heat transfer gas source 62 at its upstream end. An on / off valve 63, a flow regulator 64, a temperature control unit 65, etc., are provided at intermediate positions along the heat transfer gas supply path 61.

[0038] The heat transfer gas supply path 61 includes, for example, piping (not shown) that is inserted inside the lifting mechanism 52 and connected to the lower end of each lift pin 51. The piping is configured to have the function of allowing each lift pin 51 to move up and down, and the function of allowing the heat transfer gas to flow into the hollow section 54 without leakage. For example, the piping of the lift pins 51 and the heat transfer gas supply path 61 can be formed in a telescopic or bellows type.

[0039] Furthermore, the heat transfer gas source 62 of the heat transfer gas supply unit 60 is a high-pressure tank that stores heat transfer gas and supplies heat transfer gas to the heat transfer gas supply path 61. The on / off valve 63 switches the supply and cessation of heat transfer gas from the heat transfer gas source 62 by opening and closing the flow path of the heat transfer gas supply path 61 based on the control of the control unit 2. The flow rate regulator 64 is, for example, a mass flow controller and adjusts the flow rate of heat transfer gas supplied to the heat transfer gas supply path 61 based on the control of the control unit 2. Furthermore, the temperature adjustment unit 65 adjusts the temperature of the supplied heat transfer gas to a target temperature. Note that the temperature of the heat transfer gas can also be adjusted by adjusting the temperature of each lift pin 51 using a temperature control module (flow path 1110a, etc.) of the substrate support unit 11, and it is not necessary to provide a temperature adjustment unit 65 in the heat transfer gas supply path 61.

[0040] Furthermore, the lifter section 50 includes a sealing member 59 that prevents the heat transfer gas that has moved to each lift pin housing section 53 from escaping vertically downward from the lift pin housing section 53. The sealing member 59 is housed in a groove provided on the inner circumferential surface of the lift pin housing section 53 and airtightly seals the outer circumferential surface of the lift pin 51. The lifter section 50 allows the lift pin 51 to be raised and lowered by the lifting mechanism 52 even when the sealing member 59 is in contact with the lift pin 51.

[0041] The plasma processing apparatus 1 according to the first embodiment is basically configured as described above, and its operation will be explained below with reference to Figure 4. Figure 4 is a flowchart showing the plasma processing method of the plasma processing apparatus 1, which performs plasma processing while supplying a heat transfer gas.

[0042] The control unit 2 of the plasma processing system sequentially executes steps S101 to S103 shown in Figure 4 in the plasma processing method.

[0043] Specifically, before starting the plasma processing method, the control unit 2 controls each component of the plasma processing apparatus 1 to adjust the temperature of the substrate W placed on the substrate support 11 to a target temperature (step S101). In this temperature adjustment step, the temperature control module of the substrate support 11 adjusts the temperature of the substrate W from within the substrate support 11 using a heater or a flow path 1110a. The plasma processing apparatus 1 also supplies heat transfer gas from the heat transfer gas source 62 to the heat transfer gas supply path 61, and allows the heat transfer gas to flow from the heat transfer gas supply path 61 into the hollow portion 54 of each lift pin 51. The heat transfer gas that flows into the hollow portion 54 of each lift pin 51 moves vertically upward and is discharged upward from the opening 54o. As a result, the heat transfer gas moves through the groove 111c of the substrate support 11 and adjusts the temperature of substantially the entire surface of the substrate W.

[0044] When the temperature of the substrate W reaches the target temperature, the control unit 2 controls the gas supply unit 20 and the power supply system 30 to perform a step of generating plasma from the processing gas in the plasma processing space 10s (step S102). That is, the gas supply unit 20 supplies the processing gas into the plasma processing chamber 10. The power supply system 30 supplies RF power to the conductive member in the plasma processing chamber 10, thereby generating plasma in the processing gas.

[0045] After plasma is generated as described above, the control unit 2 controls the power supply system 30 to supply a bias to the conductive member of the substrate support unit 11, thereby performing a step of drawing active species (ions) of the plasma in the plasma processing space 10s into the substrate W (step S103). Note that the plasma processing apparatus 1 continues the supply of heat transfer gas by the heat transfer gas supply unit 60 to adjust the temperature of the substrate W even between the above-described step S102 and step S103.

[0046] Furthermore, the control unit 2 monitors whether or not to end the plasma processing (step S104). For example, the control unit 2 determines the end of the plasma processing based on whether or not the actual period measured against the processing period of the recipe has been reached. When the plasma processing is to be continued (step S104: NO), the process returns to step S102 and the same processing is repeated thereafter. On the other hand, when the plasma processing is to be ended (step S104: YES), ending processing such as stopping the gas supply unit 20, stopping the power supply system 30, and stopping the supply of heat transfer gas by the heat transfer gas supply unit 60 is performed, and the plasma processing method is ended.

[0047] As described above, the plasma processing method according to the embodiment can stably supply heat transfer gas to the back surface of the substrate W using each lift pin 51. Thereby, the plasma processing method can appropriately adjust the temperature of the substrate W to the target temperature for plasma processing. In addition, the heat transfer gas discharged from each lift pin 51 moves through the groove 111c, so that the temperature of the entire in-plane area of the substrate W can be adjusted substantially uniformly.

[0048] FIG. 5 is a diagram showing a comparison between the substrate support 11 according to the first embodiment and a conventional substrate support 11'. As shown in the left diagram of FIG. 5, the conventional substrate support 11' is provided with a plurality of holes 68 in the substrate support surface 111a for supplying heat transfer gas to the substrate W placed on the substrate support surface 111a. On the other hand, the lift pins 51 only had the function of raising and lowering the substrate W, and did not supply heat transfer gas. Alternatively, there is a configuration in which heat transfer gas is supplied through the gap between the lift pin 51 and the lift pin accommodating portion 53 as disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 2021-108334), but in this case, the amount of heat transfer gas that can be supplied through the gap is very small.

[0049] In contrast, the plasma processing apparatus 1 according to the first embodiment can supply a large amount of heat transfer gas by supplying the heat transfer gas through the hollow portion 54 in each lift pin 51. Therefore, as shown in the upper right diagram of FIG. 5, the substrate support 11 does not need to be provided with a separate hole 68 for supplying heat transfer gas. As a result, in plasma processing, it is possible to significantly reduce locations where abnormal discharge of heat transfer gas occurs on the substrate support 11 side. In addition, by eliminating the heat transfer gas holes 68, the volume of the holes 68 in the substrate support 11 is reduced, which increases the degree of freedom in design, allowing various configurations to be appropriately arranged. Consequently, the substrate support 11 can also promote performance improvement.

[0050] However, the plasma processing apparatus 1 does not need to eliminate all the holes 68 for supplying heat transfer gas. For example, as shown in the lower right diagram of FIG. 5, a substrate support 11A having a smaller number of holes 68 than the conventional substrate support 11' may be employed. The number of the holes 68 may be, for example, about 1 to 6. Each hole 68 is preferably arranged at a position separated from each lift pin 51 and the lift pin accommodating portion 53 by a predetermined distance or more (for example, 50 mm or more).

[0051] It should be noted that the substrate processing apparatus of the present disclosure is not limited to the above embodiment, and can take various modifications. For example, the substrate processing apparatus may be configured to perform other substrate processing (film formation processing, heat treatment, etc.) on the substrate W placed on the substrate support 11 without performing plasma processing.

[0052] Furthermore, in a configuration in which an opening 54o is formed on the outer circumferential surface of each lift pin 51, the upper end of each lift pin 51 may be positioned higher than the opening 53o of the lift pin housing 53 when it is in a standby position during substrate processing. This exposes the opening 54o of each lift pin 51 in a direction facing the groove 111c, allowing heat transfer gas to be smoothly discharged from this opening 54o toward the groove 111c.

[0053] Figure 6(A) is a cross-sectional view showing the substrate support portion 11B according to the second embodiment. Figure 6(B) is a perspective view showing the upper part of the lift pin 51 of the substrate support portion 11B according to the second embodiment. The substrate support portion 11B according to the second embodiment differs from the lift pin 51 according to the first embodiment in that the lift pin 51A is a solid rod and has a groove 55 extending in the axial direction on the outer circumferential surface of the lift pin 51A. That is, the heat transfer gas supply portion 60A supplies heat transfer gas to the back surface of the substrate W through the gap between the inner circumferential surface of the lift pin housing portion 53 and the outer circumferential surface of the lift pin 51 and the groove 55.

[0054] Furthermore, the lift pin 51A is formed so that its outer diameter gradually decreases from the lower end to the upper end 511, and has steps 512 and 513 in the axial direction. By forming the upper end of the lift pin 51A in this way, it becomes easier to make point contact with the substrate W, and the substrate W can be held stably.

[0055] The groove 55 extends parallel to the axial direction on the outer surface having an intermediate thickness, between the steps 512 and 513. The upper end of the groove 55 is open at the location of the step 512. Multiple grooves 55 may be provided at different circumferential positions of the lift pin 51A. The groove 55 is generally positioned to overlap the second block 15 of the substrate support 11 (base 1110) in the standby position of the lift pin 51A. However, the groove 55 may extend to the upper end of the lift pin 51A. In this case, the lift pin 51A may be configured without steps 512 and 513.

[0056] On the other hand, the heat transfer gas supply unit 60A has a horizontal passage 66 that communicates with the lift pin housing 53 and a vertical passage 67 that penetrates the first block 14 and communicates with the horizontal passage 66, located between the first block 14 and the second block 15. The heat transfer gas supply unit 60A connects a heat transfer gas supply path 61, which is connected to the heat transfer gas source 62, to the lower end of the vertical passage 67 (the port of the first block 14). In other words, the horizontal passage 66 and the vertical passage 67 are connected to the heat transfer gas supply unit 60A and also constitute passages that supply heat transfer gas to the standby position of the groove 55 of the lift pin 51.

[0057] As a result, the heat transfer gas supply unit 60A supplies heat transfer gas from the lateral passage 66 to the location of the groove 55 of the lift pin 51A, allowing a large amount of heat transfer gas to circulate vertically upward through the groove 55. The heat transfer gas also circulates between the outer surface of the lift pin 51A and the inner surface of the lift pin housing 53. Furthermore, the heat transfer gas that has moved above the groove 55 moves to the opening 53o through the gap between the outer surface of the lift pin 51A and the inner surface of the lift pin housing 53, and is discharged from the opening 53o into the groove 111c.

[0058] Furthermore, sealing members 59 are installed on the outer circumferential surface of the lift pin 51A and the inner circumferential surface of the lift pin housing 53, both on the lower end side of the groove 55. The sealing members 59 prevent the heat transfer gas supplied to the lift pin housing 53 from leaking out to the lower end.

[0059] As in the second embodiment described above, even with a configuration in which each lift pin 51A has a groove 55 on its outer circumferential surface, it is possible to stably supply heat transfer gas from each lift pin housing 53 to the back surface of the substrate W. Therefore, similar to the first embodiment, the temperature of the substrate W can be adjusted by the heat transfer gas while reducing the number of heat transfer gas holes 68 (see Figure 5).

[0060] <Note> The embodiments disclosed above include, for example, the following aspects.

[0061] [Note 1] A substrate processing apparatus comprising: a substrate support portion for supporting a substrate; a plurality of lift pins provided on the substrate support portion and capable of raising and lowering the substrate relative to the substrate support portion; and a heat transfer gas supply portion for supplying heat transfer gas to the substrate supported by the substrate support portion, wherein the plurality of lift pins are formed in a cylindrical shape having a hollow portion extending in the axial direction and an opening communicating with the hollow portion, and the heat transfer gas supply portion supplies the heat transfer gas to the back surface of the substrate through the hollow portion and the opening.

[0062] [Note 2] The substrate processing apparatus according to Note 1, wherein the openings are provided at the upper ends of the plurality of lift pins.

[0063] [Note 3] The substrate processing apparatus according to Note 1 or 2, wherein the substrate support portion comprises a plurality of lift pin housing portions that each house the plurality of lift pins, and has a sealing member that seals the outer circumferential surfaces of the plurality of lift pins and the inner circumferential surfaces of the plurality of lift pin housing portions.

[0064] [Note 4] A substrate processing apparatus comprising: a substrate support portion for supporting a substrate; a plurality of lift pins provided in the substrate support portion and capable of raising and lowering the substrate relative to the substrate support portion; a plurality of lift pin housing portions provided in the substrate support portion and housing each of the plurality of lift pins; and a heat transfer gas supply portion for supplying heat transfer gas to the substrate supported by the substrate support portion, wherein the plurality of lift pins have grooves extending in the axial direction on their outer circumferential surface, and the heat transfer gas supply portion supplies the heat transfer gas to the inside of the lift pin housing portions and through the grooves of the lift pins to the back surface of the substrate.

[0065] [Note 5] The substrate processing apparatus according to Note 4, wherein the lift pin has a plurality of steps on its outer surface, and the grooves are provided between the plurality of steps that are adjacent to each other.

[0066] [Note 6] The substrate processing apparatus according to Note 5, wherein the substrate support portion is connected to the heat transfer gas supply portion and has a passage for supplying the heat transfer gas to the standby position of the groove of the lift pin.

[0067] The substrate processing apparatus (plasma processing apparatus 1) according to the embodiments disclosed herein is illustrative and not restrictive in all respects. The embodiments can be modified and improved in various ways without departing from the scope and spirit of the appended claims. The matters described in the above-mentioned embodiments can be otherwise configured and combined in a non-consistent manner.

[0068] The substrate processing apparatus (plasma processing apparatus 1) of this disclosure is applicable to any of the following types of apparatus: Atomic Layer Deposition (ALD) apparatus, Capacitively Coupled Plasma (CCP), Inductively Coupled Plasma (ICP), Radial Line Slot Antenna (RLSA), Electron Cyclotron Resonance Plasma (ECR), and Helicon Wave Plasma (HWP).

[0069] This application claims priority to Japanese Patent Application No. 2025-053212, which was filed with the Japan Patent Office on March 27, 2025, and the entire contents of that application are incorporated herein by reference.

[0070] 1 Plasma processing apparatus 11 Substrate support section 51 Lift pin 54 Hollow section 54o Opening 60 Heat transfer gas supply section W Substrate

Claims

1. A substrate processing apparatus comprising: a substrate support portion for supporting a substrate; a plurality of lift pins provided on the substrate support portion and capable of raising and lowering the substrate relative to the substrate support portion; and a heat transfer gas supply portion for supplying heat transfer gas to the substrate supported by the substrate support portion, wherein the plurality of lift pins are formed in a cylindrical shape having a hollow portion extending in the axial direction and an opening communicating with the hollow portion, and the heat transfer gas supply portion supplies the heat transfer gas to the back surface of the substrate through the hollow portion and the opening.

2. The substrate processing apparatus according to claim 1, wherein the openings are provided at the upper ends of the plurality of lift pins, respectively.

3. The substrate support portion comprises a plurality of lift pin housing portions, each housing one of the plurality of lift pins, and a sealing member that seals the outer circumferential surfaces of the plurality of lift pins and the inner circumferential surfaces of the plurality of lift pin housing portions, as described in claim 1.

4. A substrate processing apparatus comprising: a substrate support portion for supporting a substrate; a plurality of lift pins provided in the substrate support portion and capable of raising and lowering the substrate relative to the substrate support portion; a plurality of lift pin housing portions provided in the substrate support portion and housing each of the plurality of lift pins; and a heat transfer gas supply portion for supplying heat transfer gas to the substrate supported by the substrate support portion, wherein the plurality of lift pins have grooves extending in the axial direction on their outer circumferential surface, and the heat transfer gas supply portion supplies the heat transfer gas to the back surface of the substrate through the inside of the lift pin housing portions and the grooves of the lift pins.

5. The substrate processing apparatus according to claim 4, wherein the lift pin has a plurality of steps on its outer circumferential surface, and the grooves are provided between the plurality of steps that are adjacent to each other.

6. The substrate processing apparatus according to claim 5, wherein the substrate support portion is connected to the heat transfer gas supply portion and has a passage for supplying the heat transfer gas to the standby position of the groove of the lift pin.

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