JP2022132091A - Substrate processing apparatus and substrate temperature correction method - Google Patents

Abstract

To suppress the temperature change of a substrate due to the influence of the temperature change of a temperature control medium.SOLUTION: A mounting table has a mounting surface on which a substrate is mounted, a flow path for flowing a temperature control medium is formed therein, and a discharge port for discharging heat transfer gas is formed on the mounting surface. A gas supply unit supplies heat transfer gas to be discharged from the discharge port. A measurement unit measures the temperature of the temperature control medium flowing through the flow path. When the temperature of the temperature control medium measured by the measurement unit changes by a predetermined temperature or more, the control unit controls the pressure of the heat transfer gas supplied from the gas supply unit so as to cancel the temperature change of the substrate caused by the temperature change of the temperature control medium after a predetermined time in which the temperature of the substrate mounted on the mounting surface changes due to the temperature change of the temperature control medium has elapsed from the timing of the change.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a substrate processing apparatus and a substrate temperature correction method.

Patent Document 1 discloses a technique for switching the temperature of a substrate by alternately supplying a temperature control medium with a first temperature and a temperature control medium with a second temperature to a flow path of a mounting table on which the substrate is placed. Proposed. Patent Document 2 discloses a temperature control medium controlled to a first temperature by a low temperature control unit and a temperature control medium controlled to a second temperature higher than the first temperature by a high temperature control unit. A technique has been proposed in which the temperature of the substrate is adjusted by adjusting the mixing ratio and supplying it to the flow path of the mounting table.

JP 2020-120045 A JP 2013-105359 A

The present disclosure provides a temperature control medium control method and a temperature control medium control device capable of suppressing temperature change of a substrate due to temperature change of the temperature control medium.

A substrate processing apparatus according to one aspect of the present disclosure includes a mounting table, a gas supply section, a measurement section, and a control section. The mounting table has a mounting surface on which the substrate is mounted, a flow path for flowing the temperature control medium is formed therein, and a discharge port for discharging heat transfer gas is formed on the mounting surface. The gas supply unit supplies heat transfer gas to be discharged from the discharge port. The measurement unit measures the temperature of the temperature control medium flowing through the flow path. When the temperature of the temperature control medium measured by the measurement unit changes by a predetermined temperature or more, the control unit causes the temperature of the substrate placed on the mounting surface to change due to the temperature change of the temperature control medium from the timing of the change. After a predetermined time has elapsed, the pressure of the heat transfer gas supplied from the gas supply unit is controlled so as to cancel the temperature change of the substrate caused by the temperature change of the temperature control medium.

According to the various aspects and embodiments of the present disclosure, it is possible to suppress the temperature change of the substrate due to the temperature change of the temperature control medium.

FIG. 1 is a schematic cross-sectional view showing an example of a substrate processing apparatus according to an embodiment. FIG. 2 is a diagram illustrating an example of a schematic configuration of the temperature control device according to the embodiment; FIG. 3A is a diagram for explaining the switching operation of the temperature control medium by the temperature control device according to the embodiment; FIG. 3B is a diagram for explaining the switching operation of the temperature control medium by the temperature control device according to the embodiment; FIG. 4 is a graph showing an example of changes in the temperature of the temperature control medium and the temperature of the substrate according to the embodiment. FIG. 5 is a graph showing an example of changes in the temperature of the temperature control medium and the temperature of the substrate according to the embodiment. FIG. 6 is a diagram illustrating an example of how to obtain the predetermined time according to the embodiment. FIG. 7 is a diagram showing an example of the relationship between the pressure of the heat transfer gas and the temperature of the substrate according to the embodiment. FIG. 8 is a diagram showing an example of changes in the PT curve depending on the amount of heat input from the plasma to the substrate W according to the embodiment. FIG. 9 is a diagram obtained by logarithmizing the vertical axis and the horizontal axis of FIG. FIG. 10 is a diagram illustrating an example of substrate temperature correction according to the embodiment. FIG. 11 is a diagram illustrating control of the pressure of heat transfer gas according to the embodiment. FIG. 12 is a flow chart showing an example of a substrate temperature correction method according to the embodiment. FIG. 13 is a diagram illustrating another example of substrate temperature correction according to the embodiment.

Embodiments of the disclosed substrate processing apparatus and substrate temperature correction method will be described in detail below with reference to the drawings. It should be noted that the disclosed substrate processing apparatus and substrate temperature correction method are not limited to the following embodiments.

By the way, if the temperature of the mounting table is changed by changing the temperature of the temperature control medium flowing through the flow path of the mounting table to change the temperature of the substrate, the temperature of the substrate may change due to the influence of the temperature change of the temperature control medium. There is For example, the temperature of the temperature control medium stored in the tank that stores the temperature control medium changes due to the return temperature control medium at the time of switching, and the substrate temperature changes due to the temperature change of the temperature control medium supplied from the tank. may change. In addition, when the temperature of the temperature control medium is adjusted by adjusting the mixture ratio of the temperature control medium, the temperature of the temperature control medium cannot be adjusted so that the temperature is constant, and the temperature of the temperature control medium changes. The temperature of the substrate may change due to the influence of

Substrate processing can be affected when the substrate changes in temperature. Accordingly, the present disclosure provides a technology capable of suppressing temperature change of the substrate due to the influence of temperature change of the temperature control medium.

[Embodiment]
[Configuration of substrate processing apparatus 1]
An example of the substrate processing apparatus of the present disclosure will be described. First, a substrate processing apparatus 1 according to an embodiment will be described. The substrate processing apparatus 1 performs substrate processing on a substrate W. As shown in FIG. In the embodiment, a plasma processing apparatus is used as the substrate processing apparatus 1, and a plasma processing such as plasma etching is performed on the substrate W as the substrate processing. FIG. 1 is a schematic cross-sectional view showing an example of a substrate processing apparatus 1 according to an embodiment. In this embodiment, the substrate processing apparatus 1 is, for example, a plasma etching apparatus having parallel plate electrodes. The substrate processing apparatus 1 includes an apparatus main body 10 and a control device 70 . The apparatus main body 10 is made of a material such as aluminum, and has a processing container 12 having, for example, a substantially cylindrical shape. The inner wall surface of the processing container 12 is anodized. In addition, the processing container 12 is grounded for safety.

A substantially cylindrical support 14 made of an insulating material such as quartz is provided on the bottom of the processing vessel 12 . The support portion 14 extends vertically (for example, toward the upper electrode 30 ) from the bottom of the processing container 12 in the processing container 12 .

A mounting table 11 is provided in the processing container 12 . The mounting table 11 is supported by the support portion 14 . The mounting table 11 has a mounting surface 11a on which a substrate W such as a semiconductor wafer is mounted. The substrate W is mounted on the mounting surface 11 a of the mounting table 11 . The mounting table 11 holds the substrate W mounted on the mounting surface 11a. The mounting table 11 has an electrostatic chuck ESC and a lower electrode LE. The lower electrode LE is made of a metal material such as aluminum, and has a substantially disk shape. The electrostatic chuck ESC is arranged on the lower electrode LE. The upper surface of the electrostatic chuck ESC serves as a mounting surface 11a.

The electrostatic chuck ESC has a structure in which an electrode EL, which is a conductive film, is arranged between a pair of insulating layers or between a pair of insulating sheets. A DC power supply 17 is electrically connected to the electrode EL via a switch SW. The electrostatic chuck ESC attracts the substrate W to the upper surface of the electrostatic chuck ESC by electrostatic force such as Coulomb force generated by the DC voltage supplied from the DC power supply 17 . Thereby, the electrostatic chuck ESC can hold the substrate W. FIG.

A mounting surface 11a of the mounting table 11 is formed with a discharge port 11b for discharging heat transfer gas. A heat transfer gas such as He gas is supplied to the outlet 11 b through a pipe 19 . A gas supply unit 18 is connected to the pipe 19 . The gas supply unit 18 supplies heat transfer gas to the pipe 19 . The heat transfer gas supplied through the pipe 19 is discharged from the discharge port 11b and supplied between the electrostatic chuck ESC and the substrate W. As shown in FIG. By adjusting the pressure of the heat transfer gas supplied between the electrostatic chuck ESC and the substrate W, the thermal conductivity between the electrostatic chuck ESC and the substrate W can be adjusted.

An edge ring ER is arranged around the electrostatic chuck ESC so as to surround the edge of the substrate W and the electrostatic chuck ESC. The edge ring ER is sometimes called a focus ring. The edge ring ER can improve the in-plane uniformity of processing on the substrate W. FIG. The edge ring ER is made of a material, such as quartz, which is appropriately selected according to the material of the film to be etched.

Inside the lower electrode LE, a channel 15 is formed through which a temperature control medium, which is an insulating fluid such as Galden (registered trademark), flows. A temperature control device 20 is connected to the flow path 15 via a pipe 16a and a pipe 16b. The temperature control device 20 controls the temperature of the temperature control medium flowing through the channel 15 of the lower electrode LE. The temperature control medium whose temperature is controlled by the temperature control device 20 is supplied into the flow path 15 of the lower electrode LE via the pipe 16a. The temperature control medium that has flowed through the flow path 15 is returned to the temperature control device 20 via the pipe 16b.

The temperature control device 20 switches between a temperature control medium having a first temperature and a temperature control medium having a second temperature, and supplies the temperature control medium into the flow path 15 of the lower electrode LE. By switching between the temperature control medium having the first temperature and the temperature control medium having the second temperature and supplying them into the flow path 15 of the lower electrode LE, the temperature of the electrode LE changes between the first temperature and the second temperature. switch to The temperature of the mounting table 11 is also switched between the first temperature and the second temperature. The first temperature is, for example, a temperature of 0° C. or lower. The second temperature is, for example, room temperature or higher.

A temperature sensor 21 is provided in the pipe 16a. The temperature sensor 21 measures the temperature of the temperature control medium flowing through the pipe 16a.

A feed tube 69 for supplying high-frequency power to the lower electrode LE is electrically connected to the lower surface of the lower electrode LE. The feeder tube 69 is made of metal. Although not shown in FIG. 1, in the space between the lower electrode LE and the bottom of the processing container 12, lifter pins and lifter pins for transferring the substrate W on the electrostatic chuck ESC are provided. drive mechanism and the like are arranged.

A first high-frequency power supply 64 is connected to the feeding tube 69 via a matching device 68 . The first high-frequency power supply 64 is a power supply that generates high-frequency power for attracting ions into the substrate W, that is, high-frequency bias power. generate electricity. The matching device 68 is a circuit for matching the output impedance of the first high frequency power supply 64 and the input impedance of the load (lower electrode LE) side. High-frequency bias power generated by the first high-frequency power supply 64 is supplied to the lower electrode LE via a matching device 68 and a feed tube 69 .

An upper electrode 30 is provided above the mounting table 11 and at a position facing the mounting table 11 . The lower electrode LE and the upper electrode 30 are arranged substantially parallel to each other. Plasma is generated in the space between the upper electrode 30 and the lower electrode LE, and plasma processing such as etching is performed on the substrate W held on the upper surface of the electrostatic chuck ESC by the generated plasma. A space between the upper electrode 30 and the lower electrode LE is a processing space PS.

The upper electrode 30 is supported above the processing vessel 12 via an insulating shielding member 32 made of, for example, quartz. The upper electrode 30 has an electrode plate 34 and an electrode support 36 . The lower surface of the electrode plate 34 faces the processing space PS. The electrode plate 34 is formed with a plurality of gas ejection ports 34a. The electrode plate 34 is made of a material containing silicon, for example.

The electrode support 36 is made of a conductive material such as aluminum, and detachably supports the electrode plate 34 from above. The electrode support 36 may have a water cooling structure (not shown). A diffusion chamber 36 a is formed inside the electrode support 36 . From the diffusion chamber 36a, a plurality of gas flow openings 36b communicating with the gas ejection openings 34a of the electrode plate 34 extend downward (toward the mounting table 11). The electrode support 36 is provided with a gas introduction port 36c for introducing the processing gas to the diffusion chamber 36a, and a pipe 38 is connected to the gas introduction port 36c.

A gas source group 40 is connected to the pipe 38 via a valve group 42 and a flow controller group 44 . The gas source group 40 has multiple gas sources. The valve group 42 includes a plurality of valves, and the flow controller group 44 includes a plurality of flow controllers such as mass flow controllers. Each of gas source group 40 is connected to piping 38 via a corresponding valve in valve group 42 and a corresponding flow controller in flow controller group 44 .

Thereby, the apparatus main body 10 supplies the processing gas from one or more gas sources selected in the gas source group 40 to the diffusion chamber 36a in the electrode support 36 at an individually adjusted flow rate. be able to. The processing gas supplied to the diffusion chamber 36a diffuses in the diffusion chamber 36a, and is supplied in the form of a shower into the processing space PS through the respective gas flow openings 36b and gas ejection openings 34a.

A second high-frequency power source 62 is connected to the electrode support 36 via a matching device 66 . The second high-frequency power supply 62 is a power supply that generates high-frequency power for plasma generation, and generates high-frequency power with a frequency of 27 to 100 MHz, for example, a frequency of 60 MHz. The matching device 66 is a circuit for matching the output impedance of the second high frequency power supply 62 and the input impedance of the load (upper electrode 30) side. High-frequency power generated by the second high-frequency power supply 62 is supplied to the upper electrode 30 via the matching box 66 . The second high-frequency power supply 62 may be connected to the lower electrode LE via a matching box 66. FIG.

A deposition shield 46 made of aluminum or the like whose surface is coated with Y ₂ O ₃ or quartz is detachably provided on the inner wall surface of the processing container 12 and the outer surface of the support portion 14 . Depot shield 46 prevents etching by-products (depot) from adhering to processing vessel 12 and support 14 .

An exhaust plate 48 is provided between the outer wall of the support part 14 and the inner wall of the processing container 12 and on the bottom side of the processing container 12 (the side where the support part 14 is installed). The exhaust plate 48 is made of aluminum or the like whose surface is coated with Y ₂ O ₃ or quartz. Below the exhaust plate 48, an exhaust port 12e is provided. An exhaust device 50 is connected through an exhaust pipe 52 to the exhaust port 12e.

The evacuation device 50 has a vacuum pump such as a turbomolecular pump. The exhaust device 50 can depressurize the space inside the processing container 12 to a desired degree of vacuum. A side wall of the processing chamber 12 is provided with an opening 12g for loading or unloading the substrate W. As shown in FIG. The opening 12 g can be opened and closed by a gate valve 54 .

The control device 70 is, for example, a computer. The operation of the device body 10 configured as described above is centrally controlled by the control device 70 . The control device 70 has a control section 71 and a storage section 72 . Note that the control device 70 may have a display section for displaying various information such as the processing status, and an operation section such as a keyboard for performing various input operations.

The storage unit 72 is a storage device that stores various data. For example, the storage unit 72 is a storage device such as a hard disk, SSD (Solid State Drive), or optical disk. Note that the storage unit 72 may be a rewritable semiconductor memory such as a RAM (Random Access Memory), a flash memory, or an NVSRAM (Non Volatile Static Random Access Memory).

The storage unit 72 stores an OS (Operating System) and various programs executed by the control unit 71 . For example, the storage unit 72 stores various programs including a program for executing a substrate temperature correction method, which will be described later. Furthermore, the storage unit 72 stores various data used in the programs executed by the control unit 71 . For example, the storage unit 72 stores parameter data 72a. Note that the storage unit 72 can also store other data in addition to the data exemplified above.

The parameter data 72a is data storing parameter values, which will be described later, for each processing condition of the plasma processing. Details of the parameter data 72a will be described later.

The control unit 71 is a device such as a processor that controls each unit of the apparatus body 10 . As the control unit 71, an electronic circuit such as a CPU (Central Processing Unit) or MPU (Micro Processing Unit), or an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array) can be employed. The control unit 71 has an internal memory for storing programs defining various processing procedures and control data, and executes various processing using these. The control unit 71 reads a program stored in the storage unit 72 into a memory, executes the program by a processor, and controls each unit of the apparatus main body 10 to perform plasma processing. Further, the control unit 71 performs processing of the substrate temperature correction method according to the embodiment.

[Configuration of Temperature Control Device 20]
Next, a schematic configuration of the temperature control device 20 will be described. FIG. 2 is a diagram showing an example of a schematic configuration of the temperature control device 20 according to the embodiment.

The temperature control device 20 has a first switching section 200 , a second switching section 201 , a first temperature control section 206 and a second temperature control section 207 .

The first temperature control unit 206 is connected to the pipe 16a via a pipe 220. As shown in FIG. Also, the first temperature control unit 206 is connected to the pipe 16b via a pipe 222. As shown in FIG. A first temperature control unit 206 controls the temperature of the temperature control medium to a first temperature. For example, the first temperature control unit 206 has a tank that stores the temperature control medium, and controls the temperature of the temperature control medium to a first temperature by controlling the temperature of the tank. The first temperature control unit 206 supplies the temperature control medium having the first temperature from the tank into the flow path 15 of the lower electrode LE via the pipe 220 and the pipe 16a. The temperature control medium supplied into the flow path 15 of the lower electrode LE is returned to the tank of the first temperature control section 206 via the pipe 16b and the pipe 222. FIG.

The second temperature control unit 207 is connected to the pipe 16 a and the pipe 220 at the connection position A via the pipe 227 . Also, the second temperature control unit 207 is connected to the pipe 16 b and the pipe 222 at the connection position B via the pipe 225 . A second temperature control unit 207 controls the temperature of the temperature control medium to a second temperature higher than the first temperature. For example, the second temperature control unit 207 has a tank that stores the temperature control medium, and controls the temperature of the temperature control medium to the second temperature by controlling the temperature of the tank. The second temperature control unit 207 supplies the second temperature control medium from the tank to the flow path 15 of the lower electrode LE through the pipe 227 and the pipe 16a. supply within. The temperature control medium supplied into the flow path 15 of the lower electrode LE is returned to the tank of the second temperature control section 207 via the pipe 16b and the pipe 225. FIG.

The first temperature control section 206 and the second temperature control section 207 are connected by a pipe 208 . The pipe 208 adjusts the liquid level of the tank within the first temperature control section 206 that stores the temperature control medium and the liquid level of the tank within the second temperature control section 207 that stores the temperature control medium. This prevents the temperature control medium from leaking.

The first switching unit 200 is provided at a connecting portion of the pipe 220 and the pipe 227 to the pipe 16a. The first switching unit 200 switches the temperature control medium flowing through the flow path 15 of the lower electrode LE. The first switching section 200 has a first supply valve 2000 and a second supply valve 2001 . The first supply valve 2000 is provided near the connection position A of the pipe 220 with the pipe 16a. The second supply valve 2001 is provided near the connection position A of the pipe 227 with the pipe 16a.

The second switching unit 201 is provided at a connecting portion of the pipe 222 and the pipe 225 to the pipe 16b. The second switching unit 201 switches the output destination of the temperature control medium flowing out of the flow path 15 of the lower electrode LE to the first temperature control unit 206 or the second temperature control unit 207 . The second switching section 201 has a first return valve 2010 and a second return valve 2011 . The first return valve 2010 is provided near the connection position B of the pipe 222 with the pipe 16b. The second return valve 2011 is provided near the connection position B of the pipe 225 with the pipe 16b.

In this embodiment, the first supply valve 2000, the second supply valve 2001, the first return valve 2010, and the second return valve 2011 are all two-way valves that can be switched between an open state and a closed state. be. Opening and closing of the first supply valve 2000, the second supply valve 2001, the first return valve 2010, and the second return valve 2011 are controlled by the controller 71, respectively.

Although FIG. 2 schematically shows the configuration of the temperature control device 20, the configuration of the temperature control device 20 is not limited to this. The temperature control device 20 may be configured to be capable of suppressing water hammer as described in Patent Literature 1, for example.

[Switching operation of temperature control medium]
3A and 3B are diagrams for explaining the switching operation of the temperature control medium by the temperature control device 20 according to the embodiment. In FIGS. 3A and 3B, open valves are drawn in white, and closed valves are drawn in black.

A first temperature control unit 206 controls the temperature of the temperature control medium to a first temperature. A second temperature control unit 207 controls the temperature of the temperature control medium to a second temperature higher than the first temperature.

When the temperature control medium having the first temperature is circulated through the flow path 15, the control unit 71 controls the first supply valve 2000 and the first return valve 2010 to open, and the second supply valve 2001 and the second supply valve 2001 to open. No. 2 return valve 2011 is controlled to the closed state. As a result, as shown in FIG. 3A, the temperature control medium having the first temperature is output from the first temperature control unit 206, and is supplied to the lower electrode LE via the pipe 220, the first supply valve 2000, and the pipe 16a. It is supplied into the channel 15 . Also, the temperature control medium supplied into the flow path 15 of the lower electrode LE is returned to the first temperature control section 206 via the pipe 16b, the first return valve 2010, and the pipe 222. Thereby, the mounting table 11 is controlled to the first temperature.

On the other hand, when the temperature control medium having the second temperature is circulated through the flow path 15, the control unit 71 closes the first supply valve 2000 and the first return valve 2010, and closes the second supply valve 2001. and the second return valve 2011 is controlled to be open. As a result, as shown in FIG. 3B, the temperature control medium at the second temperature is output from the second temperature control unit 207, and the lower electrode LE is supplied via the pipe 227, the second supply valve 2001, and the pipe 16a. It is supplied into the channel 15 . Also, the temperature control medium supplied into the flow path 15 of the lower electrode LE is returned to the second temperature control section 207 via the pipe 16b, the second return valve 2011, and the pipe 225. FIG. Thereby, the mounting table 11 is controlled to the second temperature.

By the way, if it is attempted to change the temperature of the substrate W by changing the temperature of the temperature control medium flowing through the flow path 15 to change the temperature of the mounting table 11, the temperature of the substrate W may change due to the influence of the temperature change of the temperature control medium. There is

For example, when changing the temperature of the temperature control medium flowing through the flow path 15 of the mounting table 11 from the first temperature to the second temperature, the control unit 71 controls the first supply valve 2000, the second supply valve 2001, the second 3A to 3B. In this case, at the time of switching, the temperature control medium at the first temperature remaining in the flow path 15 flows into the tank of the second temperature control unit 207, and the temperature of the temperature control medium in the tank changes from the second temperature. descend. A second temperature control unit 207 controls the temperature of the tank. Therefore, the temperature of the temperature control medium in the tank returns to the second temperature over time. While the temperature of the temperature control medium in the tank is decreasing from the second temperature, the temperature of the temperature control medium supplied from the second temperature control unit 207 to the flow path 15 of the mounting table 11 is maintained at the second temperature. Temporarily lowers from temperature.

Further, for example, when changing the temperature of the temperature control medium flowing through the flow path 15 of the mounting table 11 from the second temperature to the first temperature, the control unit 71 operates the first supply valve 2000 and the second supply valve 2001 , the first return valve 2010 and the second return valve 2011 are switched from the state of FIG. 3B to the state of FIG. 3A. In this case, at the time of switching, the temperature control medium at the second temperature remaining in the flow path 15 flows into the tank of the first temperature control unit 206, and the temperature of the temperature control medium in the tank changes from the first temperature. Rise. A first temperature control unit 206 controls the temperature of the tank. Therefore, the supplied temperature control medium returns to the first temperature over time. While the temperature of the temperature control medium in the tank is rising from the first temperature, the temperature of the temperature control medium supplied from the first temperature control unit 206 to the flow path 15 of the mounting table 11 is maintained at the first temperature. Temporarily rise from temperature.

An example of the temperature change of the substrate W due to the influence of temperature change of the temperature control medium flowing through the flow path 15 of the mounting table 11 will be described. FIG. 4 is a graph showing an example of changes in the temperature of the temperature control medium and the temperature of the substrate W according to the embodiment. FIG. 4 shows that after the substrate processing apparatus 1 performs the first plasma processing on the substrate W by causing the temperature control medium of the first temperature to flow through the flow path 15 of the mounting table 11 , the flow of the mounting table 11 is It shows the case where the second plasma treatment is performed by flowing the temperature control medium of the second temperature through the path 15 . FIG. 4 shows waveforms of changes in the temperature of the substrate W, changes in the actual temperature (actual temperature) of the temperature control medium supplied to the flow path 15 of the mounting table 11, and changes in the set temperature of the temperature control medium. each shown. The set temperature of the temperature control medium indicates the ideal temperature of the temperature control medium flowing through the flow path 15 of the mounting table 11 . FIG. 4 also shows a period P1 during which the first plasma processing is performed and a period P2 during which the second plasma processing is performed by supplying high-frequency power.

The temperature control device 20 circulates the temperature control medium at the first temperature through the flow path 15 of the mounting table 11 from before the period P1 of the first plasma processing. The temperature of the substrate W is the first temperature T1 before the period P1 of the first plasma processing, but rises from the first temperature T1 during the period P1 due to heat input from the plasma.

When switching from the first plasma processing to the second plasma processing, the temperature control device 20 switches the temperature control medium to be supplied from the temperature control medium having the first temperature to the temperature control medium having the second temperature. In FIG. 4, the set temperature of the temperature control medium is switched from the first temperature T1 to the second temperature T2 between periods P1 and P2. The actual temperature of the temperature control medium supplied to the channel 15 of the mounting table 11 rapidly rises to the second temperature T2 due to the switching, and is temporarily stabilized around the temperature T2. The temperature is temporarily lowered from the second temperature T2 due to the influence of the temperature control medium. The temperature of the substrate W rises and stabilizes temporarily due to heat input from the plasma during the period P2, but the temperature temporarily drops due to the temporary drop in temperature of the temperature control medium.

FIG. 5 is a graph showing an example of changes in the temperature of the temperature control medium and the temperature of the substrate according to the embodiment. The upper part of FIG. 5 shows an enlarged view of a part where the temperature control medium and the substrate W in FIG. 4 are temporarily lowered in temperature. The lower part of FIG. 5 shows the change in pressure BP of the heat transfer gas. In FIG. 5, the gas supply unit 18 supplies heat transfer gas at a constant pressure BP. The temperature of the temperature control medium is transmitted to the substrate W through the mounting table 11 . Therefore, the temperature change of the temperature control medium is transmitted to the substrate W with a delay. Therefore, the temporary temperature drop of the substrate W occurs later than the temporary temperature drop of the temperature control medium. This change in the temperature of the substrate W affects the process of the second plasma treatment.

As shown in FIGS. 4 and 5, there is a time lag between when the temperature of the temperature control medium changes and when the temperature of the substrate W changes. Therefore, it is too early to correct the pressure BP of the heat transfer gas immediately after the temperature change of the temperature control medium occurs. Therefore, the accuracy is further improved by correcting the pressure BP of the heat transfer gas after a predetermined time .DELTA.wt elapses from the timing when the temperature of the temperature control medium changes and the temperature of the substrate W changes due to the temperature change of the temperature control medium. is expected.

The predetermined time Δwt can be empirically determined. For example, the predetermined time Δwt is set by using the substrate processing apparatus 1 or an apparatus having characteristics similar to the substrate processing apparatus 1 (for example, an experimental plasma processing apparatus), and the temperature of the temperature control medium is actually changed. can be determined by measuring the period during which temperature changes occur. FIG. 6 is a diagram illustrating an example of how to obtain the predetermined time Δwt according to the embodiment. FIG. 6 shows waveforms of changes in the temperature of the substrate W shown in FIG. 5, changes in the actual temperature of the temperature control medium supplied to the flow path 15 of the mounting table 11, and changes in the set temperature of the temperature control medium. each shown. FIG. 6 also shows waveforms of changes in the temperature of the mounting table 11 . The temperature changes of the substrate W and the mounting table 11 are substantially synchronized. From the waveform of the change in the actual temperature of the temperature control medium, the elapsed time when the actual temperature of the temperature control medium temporarily drops the most is obtained. Also, from the waveform of the change in the temperature of the substrate W or the waveform of the change in the temperature of the mounting table 11, the elapsed time at which the temperature of the substrate W or the mounting table 11 temporarily drops the most is obtained. Then, the predetermined time Δwt is obtained by finding the difference between the elapsed time when the actual temperature of the temperature control medium temporarily drops the most and the elapsed time when the temperature of the substrate W or the mounting table 11 temporarily drops the most. In the example of FIG. 6, the elapsed time when the actual temperature of the temperature control medium temporarily drops the most is 106 [sec], and the elapsed time when the temperature of the substrate W or the mounting table 11 temporarily drops the most is 126 [sec]. ], the predetermined time Δwt is found to be approximately 20 [sec].

Also, the predetermined time Δwt can be determined theoretically. For example, the predetermined time Δwt can be obtained from the following formula (1).

Δwt = t1 + t2 - t3 (1)

here,
t1 is a delay time dependent on the pipe volume.
t2 is the time required for heat transfer from the temperature control medium to the substrate W;
t3 is the time from when the gas supply unit 18 receives an instruction to change the pressure of the heat transfer gas to when the pressure BP is actually changed.

t1 is the time until the temperature control medium remaining in the flow path 15 or the like flows out. t1 is determined by the installation positions of the flow path 15, the pipes 16a and 16b, and the temperature sensor 21. FIG. For example, let L be the length from the installation position of the temperature sensor 21 in the pipe 16 a to the end of the pipe 16 b that has passed through the flow path 15 . Let S be the internal cross-sectional area of the flow path 15 and the pipes 16a and 16b. Let V be the flow velocity of the temperature control medium. In this case, it is obtained by the following formula (2).

t1 = L x S/V (2)

For example, when the length L is 4.5 [m], the cross-sectional area S is 2.85E ⁻⁴ [m ² ], and the flow velocity V of the temperature control medium is 0.5 [L/sec], t1 is , is obtained from the equation (2) as follows.

t1=4.5×2.85E- ⁴ /0.5=2.6[sec]

t2 is the time it takes for the heat in the flow path 15 of the mounting table 11 to be transferred to the substrate W, that is, the time constant (τ), and is the thermal resistance between the flow path 15 of the mounting table 11 and the substrate W; It can be obtained from the heat capacity. For example, the heat resistance and heat capacity of each layer such as the electrostatic chuck ESC between the flow path 15 of the mounting table 11 and the substrate W, the lower electrode LE portion, etc. can be obtained by Equation (3).

t2 = τ = Σ (thermal resistance x heat capacity) (3)

At t3, the gas supply unit 18 receives an instruction to change the pressure of the heat transfer gas using the actual substrate processing apparatus 1 or an apparatus having characteristics similar to those of the substrate processing apparatus 1 (for example, an experimental plasma processing apparatus). , the time taken until the pressure BP is actually changed is measured.

In the mounting table 11, when the pressure of the heat transfer gas discharged from the discharge port 11b increases, the thermal conductivity between the electrostatic chuck ESC and the substrate W increases and the temperature of the substrate W decreases. Further, in the mounting table 11, when the pressure of the heat transfer gas discharged from the discharge port 11b decreases, the thermal conductivity between the electrostatic chuck ESC and the substrate W decreases, and the temperature of the substrate W rises. FIG. 7 is a diagram showing an example of the relationship between the pressure BP of the heat transfer gas and the temperature Tw of the substrate W according to the embodiment. FIG. 7 shows a PT curve showing the relationship between the pressure BP of the heat transfer gas and the temperature Tw of the substrate W. As shown in FIG. The temperature Tw of the substrate W decreases as the pressure BP of the heat transfer gas supplied from the gas supply unit 18 increases.

The relationship between the pressure BP of the heat transfer gas and the temperature Tw of the substrate W changes depending on the amount of heat input to the substrate W from the plasma. FIG. 8 is a diagram showing an example of changes in the PT curve depending on the amount of heat input Q from the plasma to the substrate W according to the embodiment. When the amount of heat input Q from the plasma to the substrate W is large, the PT curve moves upward as a whole.

FIG. 9 is a diagram obtained by logarithmizing the vertical axis and the horizontal axis of FIG. The PT curve showing the relationship between the pressure BP of the heat transfer gas and the temperature Tw of the substrate W as shown in FIG. Therefore, the PT curve can be approximated by a logarithmic function. For example, the PT curve can be represented by the following formula (4-1), and can be represented by formulas (4-1) to (4-2).

ln(T)=a×ln(P)+b (4−1)
T=P ^a ×e ^b (4-2)
here,
a and b are parameters.
T is the temperature of the substrate W;
P is the pressure of the heat transfer gas supplied.

Next, correction of the temperature of the substrate W will be described. FIG. 10 is a diagram illustrating an example of correcting the temperature of the substrate W according to the embodiment. FIG. 10 shows the PT curve, and a partially enlarged view is shown at the bottom. When the supply temperature of the temperature control medium changes by ΔT [° C.], the temperature Tw of the substrate W also changes from T to T+ΔT. Let ΔP be the correction amount of the pressure BP of the heat transfer gas in order to return the temperature Tw of the substrate W from T+ΔT to T.

Substituting (P, T+ΔT) and (P+ΔP, T) into equation (4-2) yields the following equations (5-1) and (5-2).

T+ΔT=P ^a ×e ^b (5-1)
T = (P + ΔP) ^a ×e ^b (5-2)

Eliminating T using equations (5-1) and (5-2) results in the following equation (6).

(P+ΔP) ^a × ^eb +ΔT= ^Pa × ^eb (6)

The following equation (7) is obtained by rearranging the equation (6) into an equation relating to ΔP.

ΔP=(P ^a −ΔT/e ^b ) ^1/a −P (7)

Therefore, when the parameters a and b are determined, the correction amount ΔP of the heat transfer gas pressure BP for changing the temperature Tw of the substrate W by ΔT is obtained from the equation (7).

As shown in FIG. 8, the PT curve showing the relationship between the pressure BP of the heat transfer gas and the temperature Tw of the substrate W changes depending on the amount of heat input Q to the substrate W from the plasma. The amount of heat input Q from the plasma to the substrate W changes depending on the processing conditions of the plasma processing. Therefore, the parameters a and b can be obtained in advance for each plasma processing condition by previously obtaining the PT curve for each processing condition of the plasma processing and obtaining the equation (4-2) that approximates each PT curve. can.

The parameter data 72a stores parameters a and b for each processing condition of plasma processing.

The control unit 71 controls the pressure BP of the heat transfer gas from the gas supply unit 18 so as to cancel the temperature change of the substrate W caused by the temperature change of the temperature control medium. For example, the control unit 71 determines whether the temperature of the temperature control medium measured by the temperature sensor 21 has changed by a predetermined temperature or more. The predetermined temperature is determined according to the allowable range of temperature change of the temperature control medium. The predetermined temperature is, for example, 5°C. When the temperature of the temperature control medium changes by a predetermined temperature or more, the control unit 71 causes the gas supply unit 18 to cancel the temperature change of the substrate W due to the temperature change of the temperature control medium after a predetermined time Δwt has elapsed from the timing of the change. to control the pressure BP of the heat transfer gas of

For example, when the temperature control device 20 is supplying the temperature control medium having the first temperature to the flow path 15, the control unit 71 controls the temperature of the temperature control medium measured by the temperature sensor 21 to increase from the first temperature. When the temperature has changed by a predetermined temperature or more, and when the temperature control medium of the second temperature is being supplied from the temperature control device 20 to the flow path 15, the temperature of the temperature control medium measured by the temperature sensor 21 reaches the second temperature. When the temperature has changed from the temperature by a predetermined temperature or more, the pressure BP of the heat transfer gas from the gas supply unit 18 is controlled after a predetermined time Δwt from the timing of the change. The control unit 71 increases the pressure BP of the heat transfer gas from the gas supply unit 18 when the temperature of the temperature control medium rises by a predetermined temperature or more, and increases the pressure BP of the heat transfer gas when the temperature of the temperature control medium changes by a predetermined temperature or more. The pressure BP of the heat transfer gas from the section 18 is controlled to decrease.

For example, the control unit 71 uses a relational expression showing the relationship between the pressure BP of the heat transfer gas supplied from the gas supply unit 18 and the temperature Tw of the substrate W to adjust the heat transfer gas for correcting the temperature change of the substrate W. A correction amount ΔP for the pressure BP is obtained. Specifically, the control unit 71 specifies the values of the parameters a and b corresponding to the heat input amount of the plasma processing being performed or the processing conditions of the plasma processing from the parameter data 72a when the temperature changes. The control unit 71 obtains the correction amount ΔP of the pressure BP of the heat transfer gas for correcting the temperature change of the substrate W using the equation (7) to which the specified values of the parameters a and b are applied. Then, the control unit 71 performs control to change the pressure BP of the heat transfer gas supplied from the gas supply unit 18 by the correction amount ΔP after a predetermined time Δwt from the changed timing.

FIG. 11 is a diagram illustrating control of the pressure BP of the heat transfer gas according to the embodiment. The upper part of FIG. 11 shows waveforms of changes in the actual temperature of the temperature control medium supplied to the flow path 15 of the mounting table 11 and changes in the set temperature of the temperature control medium, which are the same as in FIG. Further, the lower part of FIG. 11 shows changes in the pressure BP of the heat transfer gas. Further, the upper side of FIG. 11 shows the waveform of the change in the temperature Tw of the substrate W after correction by controlling the pressure BP of the heat transfer gas.

After the temperature of the temperature control medium measured by the temperature sensor 21 reaches a steady state, if the temperature of the temperature control medium changes by a predetermined temperature or more, the control unit 71 controls the temperature change of the substrate W due to the temperature change of the temperature control medium. The pressure BP of the heat transfer gas from the gas supply unit 18 is controlled so as to cancel out . For example, when the temperature of the temperature control medium measured by the temperature sensor 21 is within a certain range (for example, 3° C.) considered to be a steady state from the set temperature of the temperature control medium, the control unit 71 is determined to be in a steady state. Note that the control unit 71 may determine that the temperature of the temperature control medium has reached a steady state when the change in the temperature of the temperature control medium is within a certain range even for a certain period of time. When the temperature of the temperature control medium reaches a steady state, the control unit 71 determines whether the temperature of the temperature control medium measured by the temperature sensor 21 has changed by a predetermined temperature or more.

In FIG. 11, at timing ta, the temperature of the temperature control medium measured by the temperature sensor 21 changes by a predetermined temperature or more. The control unit 71 controls the pressure BP of the heat transfer gas from the gas supply unit 18 so as to cancel the temperature change of the substrate W caused by the temperature change of the temperature control medium after a predetermined time Δwt has passed from the timing ta. In FIG. 11, the flow path 15 is supplied with the temperature control medium having the second temperature. The control unit 71 controls to reduce the pressure BP of the heat transfer gas from the gas supply unit 18 at a timing tb after a predetermined time Δwt has elapsed from the timing ta. For example, the control unit 71 specifies the values of the parameters a and b corresponding to the processing conditions of the second plasma processing being performed from the parameter data 72a when the temperature of the temperature control medium changes by a predetermined temperature or more. The control unit 71 obtains the correction amount ΔP of the pressure BP of the heat transfer gas using the equation (7) to which the specified values of the parameters a and b are applied. At timing tb, the control unit 71 controls to reduce the pressure BP of the heat transfer gas supplied from the gas supply unit 18 by the correction amount ΔP.

In the mounting table 11, when the pressure of the heat transfer gas discharged from the discharge port 11b decreases, the thermal conductivity between the electrostatic chuck ESC and the substrate W decreases, and the temperature of the substrate W rises. Therefore, the temperature of the substrate W rises as the pressure BP of the heat transfer gas supplied from the gas supply unit 18 decreases. Thereby, the temperature of the substrate W is corrected as indicated by the broken line in FIG. Thus, the substrate processing apparatus 1 can suppress the temperature change of the substrate W caused by the temperature change of the temperature control medium even when the temperature of the temperature control medium flowing through the flow path 15 of the mounting table 11 changes.

[Substrate temperature compensation method]
FIG. 12 is a flow chart showing an example of a substrate temperature correction method according to the embodiment. The substrate temperature correction method exemplified in FIG. 12 is implemented by the control section 71 controlling each section of the apparatus main body 10 . The control unit 71 starts the process illustrated in FIG. 12 when the temperature of the temperature control medium reaches a steady state.

The controller 71 measures the temperature of the temperature control medium with the temperature sensor 21 (S10). The control unit 71 determines whether the temperature of the temperature control medium measured by the temperature sensor 21 has changed by a predetermined temperature or more (S11). If the temperature of the temperature control medium has not changed by the predetermined temperature or more (S11: No), the process returns to S10 described above.

On the other hand, if the temperature of the temperature control medium has changed by a predetermined temperature or more (S11: Yes), the control unit 71 retrieves the values of the parameters a and b corresponding to the processing conditions of the second plasma processing being performed from the parameter data 72a. Specify (S12). The control unit 71 obtains the correction amount ΔP of the pressure BP of the heat transfer gas for correcting the temperature change of the substrate W using the equation (7) applying the specified values of the parameters a and b (S13).

The control unit 71 determines whether a predetermined time Δwt has passed since the timing ta when the temperature of the temperature control medium changed by a predetermined temperature or more (S14). If the predetermined time Δwt has not elapsed (S14: No), the process returns to S14 described above.

On the other hand, if the predetermined time Δwt has passed (S14: Yes), the control unit 71 performs control to change the pressure BP of the heat transfer gas supplied from the gas supply unit 18 by the correction amount ΔP (S15), and ends the process. It should be noted that the control unit 71 may perform the processing of the substrate temperature correction method shown in FIG. 12 again after completing the processing.

As described above, the substrate processing apparatus 1 according to the embodiment has the mounting table 11 , the gas supply section 18 , the measurement section (the temperature sensor 21 ), and the control section 71 . The mounting table 11 has a mounting surface 11a on which the substrate W is mounted, a flow path 15 for flowing a temperature control medium is formed therein, and a discharge port 11b for discharging a heat transfer gas is formed on the mounting surface 11a. formed. The gas supply unit 18 supplies heat transfer gas to be discharged from the discharge port 11b. The measurement unit measures the temperature of the temperature control medium flowing through the flow path 15 . When the temperature of the temperature control medium measured by the measurement unit changes by a predetermined temperature or more, the control unit 71 changes the temperature of the substrate W mounted on the mounting surface 11a due to the temperature change of the temperature control medium from the timing of the change. After the lapse of a predetermined time Δwt during which a change occurs, the pressure BP of the heat transfer gas supplied from the gas supply unit 18 is controlled so as to cancel the temperature change of the substrate W caused by the temperature change of the temperature control medium. Thereby, the substrate processing apparatus 1 can suppress the temperature change of the substrate W caused by the temperature change of the temperature control medium.

In addition, when the temperature of the temperature control medium changes to a predetermined temperature or more, the control unit 71 increases the pressure BP of the heat transfer gas supplied from the gas supply unit 18, and when the temperature of the temperature control medium changes to a predetermined temperature or more, the pressure BP increases. , to reduce the pressure BP of the heat transfer gas supplied from the gas supply unit 18 . Accordingly, by increasing the pressure BP of the heat transfer gas, the thermal conductivity between the mounting table 11 and the substrate W increases, and by decreasing the pressure BP of the heat transfer gas, the heat transfer between the mounting table 11 and the substrate W increases. Since the thermal conductivity between the substrates is lowered, the temperature change of the substrate W due to the temperature change of the temperature control medium can be suppressed.

Further, the control unit 71 corrects the temperature change of the substrate W using a relational expression (for example, equation (7)) showing the relationship between the pressure BP of the heat transfer gas supplied from the gas supply unit 18 and the temperature of the substrate W. A correction amount ΔP of the pressure BP of the heat transfer gas is obtained to change the pressure BP of the heat transfer gas supplied from the gas supply unit 18 after a predetermined time Δwt has elapsed from the timing of the change. As a result, the substrate processing apparatus 1 can correct the pressure BP of the heat transfer gas by an amount corresponding to the correction of the temperature change of the substrate W, so that the temperature change of the substrate W caused by the temperature change of the temperature control medium can be reduced. .

Also, the relational expression includes parameters a and b. The storage unit 72 stores parameter data 72a in which values of parameters a and b of the relational expression are stored for each heat input amount of plasma processing or processing conditions of plasma processing. The control unit 71 stores the values of the parameters a and b corresponding to the heat input amount of the plasma processing being performed or the processing conditions of the plasma processing when the temperature of the temperature control medium measured by the measurement unit changes by a predetermined temperature or more as parameter data. Identify from 72a. Then, the control unit 71 obtains the correction amount ΔP of the pressure BP of the heat transfer gas for correcting the temperature change of the substrate W using the relational expression to which the specified values of the parameters a and b are applied. As a result, the substrate processing apparatus 1 can obtain the correction amount ΔP according to the plasma processing being performed, so that the temperature change of the substrate W caused by the temperature change of the temperature control medium can be further reduced.

In addition, the temperature control medium supply unit (temperature control device 20) circulates the temperature control medium through the flow path 15, and supplies the temperature control medium having a first temperature or a temperature control medium having a second temperature higher than the first temperature. is switched and supplied to the channel 15 . When the temperature control medium having the first temperature is supplied from the temperature control medium supply unit to the flow path 15, the control unit 71 controls the temperature of the temperature control medium measured by the measurement unit to increase from the first temperature to the predetermined temperature. When the temperature of the temperature control medium changes as described above, and when the temperature control medium of the second temperature is supplied from the temperature control medium supply unit to the flow path 15, the temperature of the temperature control medium measured by the measurement unit changes from the second temperature to When the temperature has changed by a predetermined temperature or more, the pressure BP of the heat transfer gas supplied from the gas supply unit 18 is controlled after a predetermined time Δwt has elapsed from the timing of the change. Thereby, the substrate processing apparatus 1 can suppress the temperature change of the substrate W caused by the temperature change of the temperature control medium.

Further, the predetermined time Δwt is determined by measuring the period during which the temperature of the substrate W changes after the temperature of the temperature control medium changes. As a result, the pressure BP of the heat transfer gas can be corrected at the timing when the temperature change of the temperature control medium actually occurs in the substrate W after the temperature change of the temperature control medium. can be made smaller.

Further, the predetermined time Δwt includes the delay time t1 depending on the pipe volume, the time t2 required for heat transfer from the temperature control medium to the substrate, and the actual pressure BP after instructing to change the pressure of the heat transfer gas. It is determined by calculation from the time t3 required until the change. As a result, the predetermined time Δwt can be obtained logically without measuring the predetermined time Δwt.

Although the embodiments have been described above, the embodiments disclosed this time should be considered as examples and not restrictive in all respects. Indeed, the above-described embodiments may be embodied in many different forms. Moreover, the embodiments described above may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the claims.

For example, in the above embodiments, the case where the substrate W is a semiconductor wafer has been described as an example. However, the technology disclosed is not limited. The substrate W may be any.

Further, in the above-described embodiment, the temperature control device 20 switches and supplies the temperature control medium at the first temperature T1 and the temperature control medium at the second temperature T2 to the flow path 15 of the mounting table 11. The case of controlling the temperature of the substrate W has been described as an example. However, the technology disclosed is not limited. The temperature control device 20, for example, applies a configuration such as that disclosed in Patent Document 2, and mixes a temperature control medium having a first temperature T1 and a temperature control medium having a second temperature T2 so that the set temperature is reached. The temperature of the substrate W may be adjusted by supplying it to the flow path 15 of the mounting table 11 . Even in such a case, it is possible to suppress the temperature change of the substrate W due to the temperature change of the temperature control medium.

Further, in the above-described embodiment, when the temperature control medium is switched between the first temperature T1 and the second temperature T2, the temperature control medium changes due to the influence of the temperature control medium remaining in the flow path 15. The case where it occurs is explained as an example. However, the technology disclosed is not limited. The substrate temperature correction method of the present disclosure can be applied to suppress the temperature change of the substrate W due to the temperature change of the temperature control medium, regardless of the cause of the temperature change of the temperature control medium. . FIG. 13 is a diagram illustrating another example of correction of the temperature of the substrate W according to the embodiment. In FIG. 13, a temperature change ΔT _B occurs in the temperature control medium when supplying the temperature control medium at a constant temperature to the flow path 15 of the mounting table 11, and due to the influence of the temperature change ΔT _B of the temperature control medium, A case where a temperature change ΔT _W occurs in the substrate W is shown. Even in such a case, the pressure BP of the heat transfer gas is controlled so as to cancel out the temperature change ΔT _W of the substrate W after a predetermined time Δwt has passed from the timing when the temperature change ΔT _B occurs. The temperature change ΔT _W of the substrate due to the change ΔT _B can be suppressed.

In the above embodiment, the case where the parameter data 72a storing the values of the parameters a and b of the relational expression is stored for each heat input amount of plasma processing or processing conditions of plasma processing has been described as an example. However, the technology disclosed is not limited. The storage unit 72 may store a relational expression (for example, equation (7)) to which the values of the parameters a and b corresponding to the processing conditions are applied for each heat input amount of the plasma processing or the processing conditions of the plasma processing. The control unit 71 specifies from the storage unit 72 the relational expression corresponding to the heat input amount of the plasma processing being performed or the processing conditions of the plasma processing, and uses the specified relational expression to correct the temperature change of the substrate W. A correction amount ΔP for the pressure BP of the heat transfer gas may be obtained. Further, when there is one relational expression corresponding to the plasma processing, the control unit 71 incorporates the relational expression into the program, and uses the incorporated relational expression to correct the temperature change of the substrate W. A correction amount ΔP for the gas pressure BP may be obtained.

Further, in the above-described embodiment, the case where the correction amount ΔP required to restore the temperature Tw of the substrate W when the temperature of the temperature control medium has changed by a predetermined temperature or more has been described as an example. However, the disclosed technique is not limited to this. Even if the temperature change of the temperature control medium is rapid, if the temperature change period is short, the change in the temperature Tw of the substrate W is small. On the other hand, even if the temperature change of the temperature control medium is gradual, if the temperature change period is long, the change in the temperature Tw of the substrate W is large. In this way, the change in the temperature Tw of the substrate W varies depending on the shape of the temperature change waveform of the temperature control medium. Therefore, the control unit 71 may control the pressure BP of the heat transfer gas supplied from the gas supply unit 18 according to the shape of the waveform of the temperature change when the temperature of the temperature control medium changes by a predetermined temperature or more. For example, the control unit 71 may obtain the correction amount of the pressure BP of the heat transfer gas from the shape of the waveform of temperature change of the temperature control medium. For example, for each type of waveform shape of the temperature change of the temperature control medium, a correction coefficient for correcting the correction amount ΔP is obtained by experiment or the like so as to reduce the temperature change of the substrate W, and is stored in the storage unit 72 as correction coefficient data. Remember. When the temperature change ΔT _B of the temperature control medium occurs, the control unit 71 identifies the type of waveform shape of the temperature change ΔT _B , and identifies the correction coefficient corresponding to the identified type from the correction coefficient data. The control unit 71 may correct the correction amount by multiplying the correction amount ΔP by the specified correction coefficient, and perform control to change the pressure BP of the heat transfer gas supplied from the gas supply unit 18 by the corrected correction amount. . As a result, the correction amount corresponding to the waveform of the temperature change of the temperature control medium can be obtained, so that the temperature change of the substrate can be suppressed.

Further, in the above-described embodiment, the thermal conductivity between the mounting table 11 and the substrate W is adjusted by adjusting the pressure of the heat transfer gas supplied between the mounting table 11 and the substrate W. explained in the example. However, the disclosed technique is not limited to this. A temperature control medium flows through a flow path 15 formed inside the mounting table 11, and the thermal conductivity between the temperature control medium and the mounting table 11 can be adjusted by the flow velocity of the temperature control medium. can. For example, increasing the flow velocity of the temperature control medium increases the heat transfer coefficient between the temperature control medium and the mounting table 11 . On the other hand, by slowing down the flow velocity of the temperature control medium, the heat transfer coefficient between the temperature control medium and the mounting table 11 is lowered. Therefore, when the temperature of the temperature control medium measured by the measurement unit changes by a predetermined temperature or more, the control unit 71 detects the temperature change of the substrate W due to the temperature change of the temperature control medium after a predetermined time Δwt has elapsed from the timing of the change. The thermal conductivity from the temperature control medium to the substrate W mounted on the mounting surface 11a may be adjusted so as to cancel out. When the temperature of the temperature control medium changes to be higher than a predetermined temperature, the control unit 71 increases the thermal conductivity between the temperature control medium and the substrate W placed on the mounting surface 11a so that the temperature of the temperature control medium increases. When the temperature changes below a predetermined temperature, control is performed to lower the thermal conductivity between the temperature control medium and the substrate W placed on the placement surface 11a. For example, the control unit 71 increases the flow velocity of the temperature control medium flowing through the flow path 15 when the temperature of the temperature control medium changes to a predetermined temperature or more, and increases the flow rate of the temperature control medium when the temperature of the temperature control medium changes to a predetermined temperature or more. The flow velocity of the temperature control medium flowing through the path 15 is controlled to be slow. As an example of controlling the flow velocity of the temperature control medium, when a valve is installed between the pipe 16a and the flow channel 15 or at least one of the flow channel 15 and the pipe 16b, the control is performed by adjusting the opening of the installed valve. can. Alternatively, the flow velocity of the temperature control medium may be controlled by providing a function that allows the cross-sectional area of the flow path 15 to be varied. Alternatively, the flow velocity of the temperature control medium discharged from the temperature control device 20 to the pipe 16 may be adjusted. As a result, the thermal conductivity between the temperature control medium and the substrate W placed on the placement surface 11a can be adjusted. The thermal conductivity between the temperature control medium and the mounting table 11 is part of the thermal conductivity between the temperature control medium and the substrate W mounted on the mounting surface 11a. In addition, by adjusting the pressure of the heat transfer gas supplied between the mounting table 11 and the substrate W, the thermal conductivity between the temperature control medium and the substrate W mounted on the mounting surface 11a can be adjusted. may be adjusted.

Further, in the above-described embodiments, the case of using a capacitively coupled plasma (CCP) as an example of a plasma source has been described as an example. However, the disclosed technique is not limited to this. As a plasma source, for example, an inductively coupled plasma (ICP), a microwave excited surface wave plasma (SWP), an electron cycloton resonance plasma (ECP), a helicon wave excited plasma (HWP), or the like may be used.

Further, in the above embodiment, the substrate W is subjected to plasma processing such as plasma etching, but the present invention is not limited to this. Any substrate processing may be used as long as the substrate W receives heat input. For example, substrate processing may be heat treatment such as ashing.

Further, in the above embodiment, the case where the substrate processing apparatus 1 is a plasma processing apparatus that performs plasma processing has been described as an example. However, the disclosed technique is not limited to this. The substrate processing apparatus 1 may be any apparatus as long as it performs substrate processing in which heat input to the substrate W is generated. For example, the substrate processing apparatus 1 may be a film forming apparatus, a modifying apparatus, or the like.

It should be noted that the embodiments disclosed this time should be considered as examples in all respects and not restrictive. Indeed, the above-described embodiments may be embodied in many different forms. Also, the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

LE lower electrode W substrate 1 substrate processing apparatus 10 apparatus main body 11 mounting table 11a mounting surface 11b outlet 12 processing container 15 flow path 16a piping 16b piping 18 gas supply unit 20 temperature control unit 21 temperature sensor 70 control unit 71 control unit 72 Storage unit 72a Parameter data 200 First switching unit 201 Second switching unit 206 First temperature control unit 207 Second temperature control unit 208 Piping 220 Piping 222 Piping 225 Piping 227 Piping 2000 First supply valve 2001 Second supply valve 2010 of first return valve 2011 second return valve

Claims (17)

a mounting table having a mounting surface on which a substrate is mounted, a flow path for flowing a temperature control medium formed therein, and a discharge port formed on the mounting surface for discharging a heat transfer gas;
a gas supply unit that supplies the heat transfer gas to be discharged from the discharge port;
a measurement unit that measures the temperature of the temperature control medium flowing through the flow path;
When the temperature of the temperature control medium measured by the measuring unit changes by a predetermined temperature or more, the temperature of the substrate mounted on the mounting surface changes due to the temperature change of the temperature control medium from the timing of the change. a control unit for controlling the pressure of the heat transfer gas supplied from the gas supply unit so as to cancel the temperature change of the substrate caused by the temperature change of the temperature control medium after a predetermined time has passed;
A substrate processing apparatus having The control unit increases the pressure of the heat transfer gas supplied from the gas supply unit when the temperature of the temperature control medium increases by a predetermined temperature or more, and increases the pressure of the heat transfer gas when the temperature of the temperature control medium changes by a predetermined temperature or more. 2. The substrate processing apparatus according to claim 1, wherein control is performed such that the pressure of the heat transfer gas supplied from the gas supply unit is reduced. The control unit corrects the pressure of the heat transfer gas for correcting the temperature change of the substrate using a relational expression indicating the relationship between the pressure of the heat transfer gas supplied from the gas supply unit and the temperature of the substrate. 3 . The substrate processing apparatus according to claim 1 , wherein control is performed to change the pressure of the heat transfer gas supplied from the gas supply unit by the correction amount after the predetermined time has elapsed from the timing of the change. The relational expression further includes a storage unit that stores parameter data storing the parameter values of the relational expression for each heat input amount of plasma processing or processing conditions of plasma processing,
When the temperature of the temperature control medium measured by the measurement unit changes by a predetermined temperature or more, the control unit obtains a parameter value corresponding to the heat input amount of the plasma processing being performed or the processing conditions of the plasma processing from the parameter data. 4. The substrate processing apparatus according to claim 3, wherein a correction amount of the pressure of the heat transfer gas for correcting the temperature change of the substrate is calculated using the relational expression to which the specified parameter value is applied. The control unit controls the pressure of the heat transfer gas supplied from the gas supply unit according to the shape of the waveform of the temperature change when the temperature of the temperature control medium measured by the measurement unit changes by a predetermined temperature or more. The substrate processing apparatus according to any one of claims 1 to 4. The flow path and the temperature control medium circulate, and the temperature control medium is supplied to the flow path by switching between a temperature control medium having a first temperature and a temperature control medium having a second temperature higher than the first temperature. further having a part
When the temperature control medium having the first temperature is supplied from the temperature control medium supply unit to the flow path, the control unit controls the temperature of the temperature control medium measured by the measurement unit to be the first temperature control medium. and when the temperature control medium at the second temperature is supplied from the temperature control medium supply unit to the flow path, the temperature control measured by the measurement unit When the temperature of the medium changes from the second temperature by a predetermined temperature or more, the pressure of the heat transfer gas supplied from the gas supply unit is controlled after the predetermined time has elapsed from the timing of the change. The substrate processing apparatus according to any one of . The flow path and the temperature control medium circulate, and the temperature control medium having a first temperature and the temperature control medium having a second temperature higher than the first temperature are mixed so as to reach a set temperature, and the temperature control medium is mixed to reach a set temperature. further having a temperature control medium supply unit for supplying to the passage,
When the temperature control medium mixed so as to reach the set temperature is supplied from the temperature control medium supply unit to the flow channel, the control unit controls the temperature of the temperature control medium measured by the measurement unit. 6. The method according to any one of claims 1 to 5, wherein when the temperature changes from the set temperature by a predetermined temperature or more, the pressure of the heat transfer gas supplied from the gas supply unit is controlled after the predetermined time has elapsed from the timing of the change. A substrate processing apparatus as described. The substrate processing apparatus according to any one of claims 1 to 7, wherein the predetermined time is determined by measuring a period during which the temperature of the substrate changes after the temperature of the temperature control medium changes. The predetermined time includes a delay time dependent on the pipe volume, the time required for heat transfer from the temperature control medium to the substrate, and the time from the instruction to change the pressure of the heat transfer gas until the pressure is actually changed. 8. The substrate processing apparatus according to any one of claims 1 to 7, wherein the substrate processing apparatus is determined by calculation from the time required for . The flow path of the mounting table having a mounting surface on which the substrate is mounted, a flow path for flowing a temperature control medium formed therein, and a discharge port for discharging a heat transfer gas formed in the mounting surface. A step of measuring the temperature of the temperature control medium flowing into the
When the measured temperature of the temperature control medium changes by a predetermined temperature or more, a predetermined time elapses from the timing of the change, at which temperature change occurs in the substrate mounted on the mounting surface due to the temperature change of the temperature control medium. a step of later controlling the pressure of the heat transfer gas discharged from the discharge port so as to cancel the temperature change of the substrate due to the temperature change of the temperature control medium;
A substrate temperature correction method comprising: a mounting table having a mounting surface on which the substrate is mounted and a flow path for flowing the temperature control medium formed therein;
a measurement unit that measures the temperature of the temperature control medium flowing through the flow path;
When the temperature of the temperature control medium measured by the measuring unit changes by a predetermined temperature or more, the temperature of the substrate mounted on the mounting surface changes due to the temperature change of the temperature control medium from the timing of the change. After the elapse of a predetermined time, the thermal conductivity between the temperature control medium and the substrate placed on the mounting surface is adjusted so as to cancel the temperature change of the substrate caused by the temperature change of the temperature control medium. Department and
A substrate processing apparatus having When the temperature of the temperature control medium changes to be higher than a predetermined temperature, the control unit increases the thermal conductivity between the temperature control medium and the substrate placed on the mounting surface, and increases the temperature control medium. 12 . The substrate processing apparatus according to claim 11 , wherein control is performed so as to lower the thermal conductivity between the temperature control medium and the substrate placed on the placement surface when the temperature of the substrate changes lower than a predetermined temperature. The mounting table has a discharge port formed on the mounting surface for discharging a heat transfer gas,
Further, a gas supply unit for supplying the heat transfer gas to be discharged from the discharge port,
13. The substrate processing apparatus according to claim 11, wherein the control section controls the pressure of the heat transfer gas supplied from the gas supply section. The control unit increases the pressure of the heat transfer gas supplied from the gas supply unit when the temperature of the temperature control medium increases by a predetermined temperature or more, and increases the pressure of the heat transfer gas when the temperature of the temperature control medium changes by a predetermined temperature or more. 14. The substrate processing apparatus according to claim 13, wherein the pressure of the heat transfer gas supplied from the gas supply unit is reduced. The substrate processing apparatus according to claim 11 or 12, wherein the control section controls a flow velocity of the temperature control medium flowing through the flow path. The control unit increases the flow velocity of the temperature control medium flowing through the flow path when the temperature of the temperature control medium has changed to a predetermined temperature or higher, and when the temperature of the temperature control medium has changed to a predetermined temperature or more to a lower temperature, 16. The substrate processing apparatus according to claim 15, wherein control is performed so as to slow down the flow velocity of the temperature control medium flowing through the channel. The control unit controls the substrate mounted on the mounting surface from the flow path according to the shape of the waveform of the temperature change when the temperature of the temperature control medium measured by the measurement unit changes by a predetermined temperature or more. The substrate processing apparatus according to any one of Claims 11 to 16, wherein the thermal conductivity between is adjusted.

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