JP7601508B2 - Temperature measuring device and temperature measuring method - Google Patents

Description

This disclosure relates to a temperature measurement device and a temperature measurement method.

For example, a temperature measurement method using a substrate-type temperature sensor is known in a substrate processing apparatus that performs a desired process on a substrate.

Patent document 1 discloses a wafer-type temperature sensor that includes a wafer, a top surface of the wafer divided into a number of regions, and a number of temperature sensors arranged in each of the divided regions, each of which includes a surface acoustic wave element that, in response to a high-frequency signal being input, returns a frequency signal based on the temperature of the corresponding region within a different frequency band for each of the regions.

Patent document 2 discloses a temperature measurement substrate used in a heat treatment device that applies heat treatment to a substrate to be processed, the temperature measurement substrate comprising a substrate body, a vibrator having a piezoelectric element and provided on the substrate body, and an antenna portion connected to the vibrator and provided on the peripheral side of the substrate body.

JP 2007-171047 A JP 2012-230933 A

In substrate processing equipment in which multiple substrates are placed on a rotating table that rotates inside a chamber, communication takes place between the substrate-type temperature sensor placed on the rotating table and the parent antenna, but there is a risk that communication may become unstable, causing the measured temperature to also become unstable.

In one aspect, the present disclosure provides a temperature measurement device and a temperature measurement method that can perform stable temperature measurement by performing stable communication control.

In order to solve the above problem, according to one aspect, in a substrate processing apparatus including a chamber and a turntable provided within the chamber and having a plurality of substrate placement sections on an upper surface thereof, and performing substrate processing by placing a substrate on the substrate placement section, a temperature measurement device is provided for measuring a temperature of a substrate shaped member placed on the substrate placement section at a timing when the substrate processing apparatus is not performing the substrate processing, the temperature measurement device having a plurality of SAW sensors for detecting the substrate shaped member and the temperature of the substrate shaped member, the temperature measurement device including one or more substrate type temperature sensors placed on the substrate placement section of the rotating turntable, an antenna for transmitting and receiving an electrical signal, and an electrical signal in a predetermined frequency band including a resonant frequency of the SAW sensor via the antenna. There is provided a temperature measuring device comprising a transmitting unit that transmits an electrical signal of the SAW sensor, a receiving unit that receives an electrical signal transmitted from the SAW sensor via the antenna, a temperature calculation unit that calculates the detected temperature of the SAW sensor based on the electrical signal received by the receiving unit, and a position sensor that outputs a signal when the turntable is positioned at a predetermined home position , wherein the transmitting unit transmits an electrical signal of the frequency band regardless of the rotational position of the turntable while the turntable rotates, the receiving unit captures the electrical signal received by the antenna a predetermined time after the position sensor outputs a signal, and the temperature calculation unit calculates the detected temperature of the SAW sensor based on the electrical signal captured by the receiving unit.

According to one aspect, it is possible to provide a temperature measurement device and a temperature measurement method that can perform stable temperature measurement by performing stable communication control.

1 is a schematic cross-sectional view showing an example of a substrate processing apparatus; FIG. 2 is a diagram for explaining a structure inside a chamber according to an embodiment. FIG. 2 is a diagram illustrating an example of a hardware configuration of a control unit according to the embodiment. FIG. 1 is a diagram showing an example of a substrate-type temperature sensor. 4 is a flowchart illustrating an example of a temperature measuring method according to the embodiment. 4 is a time chart showing an example of a temperature measuring method.

Below, a description will be given of a mode for carrying out the present disclosure with reference to the drawings. In each drawing, the same components are given the same reference numerals, and duplicate descriptions may be omitted.

[Substrate Processing Apparatus]
Before describing the temperature measuring device 200 according to the present embodiment, a substrate processing apparatus in which the temperature is measured using the temperature measuring device 200 will be described with reference to Figures 1 to 3. Figure 1 is a schematic cross-sectional view showing an example of a substrate processing apparatus.

The substrate processing apparatus has a chamber 1 having a substantially circular planar shape, and a rotating table (susceptor) 2 that is provided within the chamber 1 and has a center of rotation at the center of the chamber 1. The chamber 1 has a container body 12 having a cylindrical shape with a bottom, and a top plate 11 that is detachably and airtightly arranged on the upper surface of the container body 12 via a sealing member 13 such as an O-ring.

The rotating table 2 is fixed at its center to a cylindrical core 21, which is fixed to the upper end of a rotating shaft 22 extending in the vertical direction and rotatably provided. The rotating shaft 22 penetrates the bottom 14 of the chamber 1, and its lower end is attached to a drive unit 23 that rotates the rotating shaft 22 around the vertical axis. The rotating shaft 22 and the drive unit 23 are housed in a cylindrical case body 20 with an open top. A bellows 16 is provided between the bottom 14 of the container main body 12 and the case body 20. As a result, the case body 20 is airtightly attached to the lower surface of the bottom 14 of the chamber 1, and the internal atmosphere of the case body 20 is isolated from the external atmosphere. The drive unit 23 may be a motor.

The substrate processing apparatus is also provided with a position sensor 25 that detects when the turntable 2, which rotates around the rotation axis 22, is positioned at a home position (a predetermined rotation angle position). The position sensor 25 is, for example, a magnetic rotation detection sensor, a proximity sensor, a photosensor, or the like, and outputs a signal when the turntable 2 is positioned at a predetermined rotation angle position (home position). The position sensor 25 may be a sensor that detects the rotation angle of the turntable 2, such as a resolver or an encoder. The detection signal of the position sensor 25 is input to the control unit 100. Although the position sensor 25 is illustrated near the drive unit 23 in FIG. 1, the position at which the position sensor 25 is provided is not limited to this position.

In addition, a lifting mechanism 17 is provided outside the bellows 16, which can raise and lower the turntable 2 and change the height of the turntable 2. The lifting mechanism 17 raises and lowers the turntable 2, and is configured to be able to change the distance between the ceiling surface 45 and a wafer (not shown) placed in a recess 24 (described later) in response to the raising and lowering of the turntable 2. The lifting mechanism 17 may be realized in various configurations as long as it can raise and lower the turntable 2, but for example, it may be a structure in which the length of the rotation shaft 22 is expanded and contracted by gears or the like.

A first exhaust port 610 is provided on the outer edge of the chamber 1 and is connected to an exhaust pipe 630. The exhaust pipe 630 is connected to a vacuum pump 640 via a pressure regulator 650, and is configured so that the inside of the chamber 1 can be exhausted from the first exhaust port 610.

2 is a diagram for explaining the structure inside the chamber 1, and shows the structure inside the chamber 1 when the substrate processing apparatus according to the embodiment is viewed from above, with the top plate 11 omitted. On the surface of the turntable 2, a circular recess 24 is provided along the rotation direction (circumferential direction) as shown in FIG. 2 for placing multiple (five in the illustrated example) semiconductor wafers (hereinafter referred to as "substrates" or "wafers"). In addition, the recess 24 is designed to be able to place a substrate-type temperature sensor 210 of the same shape instead of a wafer. Note that FIG. 1 shows a state in which the substrate-type temperature sensor 210 is placed in the left and right recesses 24. Also, FIG. 2 shows a state in which the substrate-type temperature sensor 210 is placed in one recess 24. This recess 24 has an inner diameter slightly (e.g., 2 mm) larger than the diameter of the wafer (e.g., 300 mm) and a depth approximately equal to the thickness of the wafer, and is a placement portion on which the wafer can be placed. Therefore, when a wafer is placed in the recess 24, the surface of the wafer and the surface of the turntable 2 (the area where the wafer is not placed) are at the same height. The bottom surface of the recess 24 is formed with through holes (not shown) through which, for example, three lift pins pass to support the back surface of the wafer and lift the wafer. The transfer port 15 transfers the wafer between the external transfer arm 10 and the turntable 2.

A reaction gas nozzle 31, a reaction gas nozzle 32, and a separation gas nozzle 41, 42, each made of, for example, quartz, are arranged above the turntable 2. In the illustrated example, the separation gas nozzle 41, the reaction gas nozzle 31, the separation gas nozzle 42, and the reaction gas nozzle 32 are arranged in this order at intervals around the circumference of the chamber 1, clockwise from the transfer port 15 (the direction of rotation of the turntable 2). These nozzles 41, 31, 42, 32 have their respective base ends, that is, gas introduction ports 41a, 31a, 42a, 32a, fixed to the outer peripheral wall of the container body 12. As a result, the nozzles are introduced into the chamber 1 from the outer peripheral wall of the chamber 1 and are attached so as to extend parallel to the turntable 2 along the radial direction of the container body 12.

A first reaction gas supply source in which a first reaction gas is stored is connected to the reaction gas nozzle 31 via an on-off valve and a flow regulator (both not shown). A second reaction gas supply source in which a second reaction gas that reacts with the first reaction gas is stored is connected to the reaction gas nozzle 32 via an on-off valve and a flow regulator (both not shown).

In addition, a supply source of a rare gas such as Ar or He or an inert gas such as nitrogen ( _N2 ) gas is connected to the separation gas nozzles 41, 42 via an opening/closing valve or a flow rate regulator (both not shown). The inert gas supplied from the separation gas nozzles 41, 42 is also referred to as a separation gas.

The reaction gas nozzle 31 is connected to a first reaction gas supply source, a second reaction gas supply source, and a supply source of an inert gas used as a separation gas such as a rare gas such as Ar or He, or nitrogen ( _N2 ) gas. The nozzle is provided so that a switching unit (not shown) can be operated to switch which gas is supplied. The reaction gas nozzle 32 is connected to a second reaction gas supply source, a first reaction gas supply source, and a supply source of an inert gas used as a separation gas. The nozzle is provided so that a switching unit (not shown) can be operated to switch which gas is supplied.

The area defined below the reaction gas nozzle 31 becomes a first processing area P1 for adsorbing the first reaction gas onto the wafer. The area defined below the reaction gas nozzle 32 becomes a second processing area P2 for reacting the first reaction gas adsorbed onto the wafer in the first processing area P1 with a second reaction gas.

In the chamber 1, two convex portions 4 are attached to the back surface of the top plate 11 so as to protrude toward the rotary table 2. The convex portions 4, together with the separation gas nozzles 41 and 42, constitute the separation region D. That is, the region below the separation gas nozzles 41 and 42 separates the first processing region P1 from the second processing region P2, and serves as the separation region D that prevents the first reaction gas from mixing with the second reaction gas. The convex portions 4 have a generally fan-shaped planar shape with the top cut into an arc shape, and in this disclosure, the inner arc is connected to the protruding portion 5 (see FIG. 1) that protrudes beyond the ceiling surface 45, and the outer arc is arranged so as to follow the inner circumferential surface of the vessel body 12 of the chamber 1. As shown in FIG. 1, the protruding portion 5 is provided so as to surround the outer periphery of the core portion 21 that fixes the rotary table 2.

The convex portion 4 shown in FIG. 2 is attached to the underside of the top plate 11. Therefore, the lower surface of the convex portion 4 is lower than the ceiling surfaces 45 located on both sides of the lower surface in the circumferential direction.

Each of the convex portions 4 has a groove portion (not shown) formed in the circumferential center, and the separation gas nozzles 41, 42 are housed in the groove portion. The separation gas nozzles 41, 42 have gas discharge holes formed therein.

The reaction gas nozzles 31, 32 are provided near the wafer, spaced apart from the ceiling surface 45. The separation gas supplied from the separation gas nozzle 42 acts as a counterflow to the first reaction gas from the first processing region P1 and the second reaction gas from the second processing region P2. Therefore, the first reaction gas from the first processing region P1 and the second reaction gas from the second processing region P2 are separated by the convex portion 4 and the separation gas. This prevents the first reaction gas and the second reaction gas from mixing and reacting in the chamber 1.

A first exhaust port 610 and a second exhaust port 620 are formed between the turntable 2 and the inner peripheral surface of the container body 12. A pressure regulator (APC, Auto Pressure Controller) 650 is provided in an exhaust pipe 630 between the first exhaust port 610 and the vacuum pump 640 shown in FIG. 1. Similarly, the second exhaust port 620 is connected to a vacuum pump (not shown) via an exhaust pipe provided with a pressure regulator. The exhaust pressures of the first exhaust port 610 and the second exhaust port 620 are configured to be independently controllable.

As shown in FIG. 1, a heater unit 7, which is a heating means, is provided in the space between the turntable 2 and the bottom 14 of the chamber 1. The heater unit 7, which is provided below the turntable 2, heats the wafer on the turntable 2 via the turntable 2 to a temperature (e.g., 450°C) determined by the process recipe.

The case body 20 is provided with a purge gas supply pipe 72 for supplying a purge gas (e.g., _N2 gas) for purging. Furthermore, a plurality of purge gas supply pipes 73 for purging the arrangement space of the heater unit 7 are provided at a predetermined angular interval in the circumferential direction below the heater unit 7 on the bottom 14 of the chamber 1. A ring-shaped cover member 71 is provided below the periphery of the turntable 2, and a lid member 7a for covering the heater unit 7 is provided between the heater unit 7 and the turntable 2. The lid member 7a can be made of, for example, quartz. This prevents gas from entering the area where the heater unit 7 is provided.

By supplying purge gas from the purge gas supply pipes 72 and 73, the flow of purge gas can prevent the gas in the space 481 and the space 482 shown in FIG. 2 from mixing through the space below the center of the chamber 1 and the space below the turntable 2.

A separation gas supply pipe 51 is connected to the center of the top plate 11 of the chamber 1, and is configured to supply a separation gas (e.g., _N2 gas) to a space 52 between the top plate 11 and the core part 21. The separation gas supplied to the space 52 is discharged toward the periphery along the surface of the turntable 2 on the wafer placement area side through a narrow space 50 between the protrusion 5 and the turntable 2. The space 50 can be maintained at a higher pressure than the spaces 481 and 482 by the separation gas. Therefore, the space 50 prevents the first reaction gas supplied to the first processing region P1 and the second reaction gas supplied to the second processing region P2 from mixing through the space 52.

The substrate processing apparatus is provided with a control unit 100 that controls the operation of the substrate processing apparatus. Various sensors are installed in the substrate processing apparatus.

Next, an example of the hardware configuration of the control unit 100 according to the embodiment will be described with reference to FIG. 3. The control unit 100 has a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, an I/O port 104, an operation panel 105, and a HDD 106 (Hard Disk Drive). Each unit is connected by a bus B.

The CPU 101 controls the operation of the control unit 100 based on programs stored in a storage device such as the HDD 106, process recipes for performing film formation processing and cleaning processing, and the like. For example, the programs include a program for executing a control method for the turntable 2. The CPU 101 controls the film formation processing of a wafer placed on the turntable 2 based on the process recipe. The CPU 101 also controls the cleaning processing in the chamber 1 based on the cleaning recipe. During idle times when the film formation processing and cleaning processing are not being performed, the CPU 101 controls the elevation and lowering of the turntable 2 based on a program for executing a control method for the turntable 2.

The ROM 102 is composed of an EEPROM (Electrically Erasable Programmable ROM), a flash memory, a hard disk, etc., and is a storage medium that stores the programs and recipes of the CPU 101. The RAM 103 functions as a work area for the CPU 101, etc.

The I/O port 104 acquires the values of various sensors that detect temperature, pressure, gas flow rate, etc. from various sensors attached to the substrate processing apparatus, and transmits them to the CPU 101. The I/O port 104 also outputs control signals output by the CPU 101 to each part of the substrate processing apparatus (rotary table 2, vacuum pump 640, etc.). The I/O port 104 is also connected to an operation panel 105 that enables an operator to operate the substrate processing apparatus.

HDD 106 is an auxiliary storage device, and may store process recipes, which are information that specifies the procedures for film formation and cleaning processes, and programs that execute methods for controlling the turntable 2 during idle time.

In this way, the substrate processing apparatus can alternately and repeatedly process a wafer placed in the recess 24 by adsorbing a first reactive gas onto the wafer in the first processing region P1 and reacting the first reactive gas adsorbed onto the wafer with a second reactive gas in the second processing region P2.

<Temperature measuring device>
Next, the temperature measuring device 200 will be described with reference to Figures 1, 2 and 4. As shown in Figure 1, the temperature measuring device 200 includes a substrate-type temperature sensor 210, a reader antenna 220 and a control unit 230. In the following description, the substrate-type temperature sensor 210 will also be referred to as a child device of the temperature measuring device 200, and the substrate-type temperature sensor 210 and the reader antenna 220 will also be referred to as a parent device of the temperature measuring device 200.

Figure 4 is a diagram showing an example of a substrate-type temperature sensor 210. The substrate-type temperature sensor 210 has a substrate-shaped member 211 and a SAW (Surface Acoustic Wave) sensor 212.

The substrate-shaped member 211 is a disk-shaped member formed of the same diameter, thickness, and material (e.g., Si) as the wafer to be processed in the substrate processing apparatus. This allows the substrate-type temperature sensor 210 to be transported by the transport arm 10 in the same way as the wafer, and to be placed in the recess 24 in the same way as the wafer. In the example of FIG. 2, the turntable 2 has five recesses 24, and the substrate-type temperature sensor 210 is shown installed in one recess 24, but this is not limited to this, and the substrate-type temperature sensor 210 may also be installed in the other recesses 24.

The SAW sensor 212 is provided on the top surface of the substrate-shaped member 211 or on a recessed portion formed on the top surface. One or more SAW sensors 212 are provided for the substrate-shaped member 211. For example, the top surface of the substrate-shaped member 211 is divided into a number of regions, and a SAW sensor 212 is provided corresponding to each divided region. The SAW sensor 212 has a communication function that enables wireless communication with the reader antenna 220.

The SAW sensor 212 receives the electrical signal transmitted by the reader antenna 220 and transmits to the reader antenna 220 an electrical signal (communication signal) including identification information for identifying the SAW sensor 212 and temperature information measured by the SAW sensor 212.

Figure 4 shows an enlarged example of a SAW sensor 212. The SAW sensor 212 is composed of a SAW device 213 and a tag antenna 214. The SAW device 213 has, for example, a comb-shaped electrode 213a on a piezoelectric substrate. The electrode 213a has electrodes 213a1 and 213a2 made of thin metal films, and is formed into a comb shape by inserting the convex parts of each into the concave parts of the other from opposite directions. An electrode member 215 electrically connected to the electrodes 213a1 and 213a2 is arranged on the tag antenna 214.

A voltage is applied between electrodes 213a1 and 213a2 from electrode member 215. When an electrical signal transmitted from reader antenna 220 is input, the crystal particles (atoms) that make up SAW device 213 are subjected to stress due to the piezoelectric effect of the piezoelectric substrate of SAW device 213 on which electrode 213a is formed, and move closer to or farther away due to the piezoelectric effect. This causes the surface of SAW sensor 212 to vibrate in a wavy manner.

The distance between electrode 213a1 and electrode 213a2 is different for each SAW sensor 212. In other words, the SAW sensors 212 have the same configuration of the SAW device 213 and tag antenna 214, but only the distance between electrode 213a1 and electrode 213a2 is different. With this configuration, of the electrical signals input to electrode 213a, the electrical signal of a frequency specific to each SAW sensor 212, which corresponds to the distance between electrode 213a1 and electrode 213a2, becomes stronger due to resonance and is propagated to the outside.

The reader antenna 220 transmits an electrical signal in a predetermined frequency band. The reader antenna 220 also receives an electrical signal of a desired frequency that is selectively extracted from each of the SAW sensors 212 in response to the transmitted electrical signal. The temperature measuring device 200 predicts the temperature based on the change in frequency of the electrical signal output by each of the SAW sensors 212. Since the resonant frequency assigned to each SAW sensor 212 is different, it is possible to determine at which position of the SAW sensor 212 the predicted temperature is based on the resonant frequency contained in the electrical signal output by the SAW sensor 212. This makes it possible to predict the temperature at each position of the SAW sensor 212 using the substrate-type temperature sensor 210.

An opening 18 is formed in the top plate 11 of the second processing region P2. In addition, dielectric windows 18a, 18b made of quartz or the like are provided in the opening 18 via a sealing member (not shown), and the opening 18 is airtightly closed. A reader antenna 220 is provided outside the chamber 1 in correspondence with the opening 18. Note that in FIG. 2, an example of the position where the reader antenna 220 is provided (the position where the opening 18 and the dielectric windows 18a, 18b are provided) is shown by a two-dot chain line. That is, the reader antenna 220 is positioned so that the substrate-type temperature sensor 210, which moves with the rotation of the turntable 2, passes under the reader antenna 220.

In FIG. 2, the position where the opening 18 and the dielectric windows 18a, 18b are provided is illustrated as the second processing region P2, but this is not limited thereto and may be the first processing region P1 or the separation region D. In addition, in FIG. 1 and FIG. 2, the position where the opening 18 and the dielectric windows 18a, 18b are provided is illustrated as the top plate 11, but this is not limited thereto and the opening and the dielectric windows may be provided in the side wall of the container body 12.

The control unit 230 includes a transmitting unit 231, a receiving unit 232, a sensor position estimating unit 233, and a temperature calculating unit 234. The control unit 230 is connected to the reader antenna 220. The control unit 230 is also connected to the control unit 100 so as to be able to communicate with it.

The transmitter 231 transmits an electrical signal in a predetermined frequency band via the reader antenna 220.

The receiving unit 232 receives the electrical signal output from the SAW sensor 212 via the reader antenna 220.

The sensor position estimation unit 233 acquires the signal of the position sensor 25 via the control unit 100. The sensor position estimation unit 233 calculates the rotation speed of the turntable 2 based on the period of the signal of the position sensor 25. The sensor position estimation unit 233 may acquire the rotation speed of the turntable 2 from the control unit 100. The sensor position estimation unit 233 can then calculate the rotation angle of the turntable 2 based on the elapsed time from the timing of acquiring the signal of the position sensor 25 and the rotation speed of the turntable 2. That is, the sensor position estimation unit 233 can estimate the position of the substrate-type temperature sensor 210 (SAW sensor 212) arranged in the recess 24 of the turntable 2. In other words, the sensor position estimation unit 233 can estimate the positional relationship between the reader antenna 220 and the substrate-type temperature sensor 210 (SAW sensor 212).

The temperature calculation unit 234 calculates the temperature measured by the SAW sensor 212 based on the electrical signal output from the SAW sensor 212 received by the receiving unit 232.

<Temperature measurement process>
Next, a temperature measurement process using the temperature measurement device 200 in the substrate processing apparatus will be described with reference to Fig. 5. Fig. 5 is a flowchart showing an example of a temperature measurement process using the temperature measurement device 200. Note that the process of the flowchart shown in Fig. 5 is performed, for example, when generating a recipe or the like for a production process before a production process in which a desired process is performed on a wafer in the substrate processing apparatus.

Here, a substrate-type temperature sensor 210 is placed in the recess 24 of the turntable 2. The substrate-type temperature sensor 210, like the wafer, is transported from the transport port 15 to the chamber 1 by the external transport arm 10, and the substrate-type temperature sensor 210 is handed over to and from the turntable 2.

In step S101, the control unit 100 controls the drive unit 23 to start rotating the susceptor (rotary table 2). The control unit 100 of the substrate processing apparatus and the control unit 230 of the temperature measuring device 200 are communicatively connected, and the detection signal of the position sensor 25 is input to the control unit 230. The transmitting unit 231 transmits an electrical signal of a predetermined frequency band from the reader antenna 220. That is, the transmitting unit transmits an electrical signal of a frequency band that includes the resonant frequencies of all the SAW sensors 212. The receiving unit 232 receives the electrical signal output from the SAW sensor 212 via the reader antenna 220.

In step S102, the control unit 230 determines whether or not it is the timing when the SAW sensor 212 is directly below the reader antenna 220. Here, the sensor position estimation unit 233 of the control unit 230 estimates the rotation angle of the turntable 2 (the positional relationship between the reader antenna 220 and the substrate-type temperature sensor 210 and the SAW sensor 212) based on the detection signal of the position sensor 25 (the time elapsed since the detection signal of the position sensor 25 was detected). In this way, the control unit 230 determines whether or not it is the timing when the SAW sensor 212 is directly below the reader antenna 220.

If the timing is not such that the SAW sensor 212 is directly below the reader antenna 220 (S102, No), the control unit 230 repeats the process of step S102. If the timing is such that the SAW sensor 212 is directly below the reader antenna 220 (S102, Yes), the control unit 230 proceeds to step S103.

In step S103, the control unit 230 performs a communication capture process between the reader antenna 220 and the SAW sensor 212. Here, the transmission unit 231 transmits an electrical signal in a predetermined frequency band (a frequency band including the resonant frequencies of all the SAW sensors 212) via the reader antenna 220. The SAW sensor 212 receives the electrical signal from the reader antenna 220 and transmits an electrical signal of a resonant frequency including temperature information. The reception unit 232 receives the electrical signal via the reader antenna 220. Here, the reception unit 232 captures, from among the electrical signals received via the reader antenna 220, an electrical signal in a frequency band corresponding to the SAW sensor 212 determined to be directly below the reader antenna 220 in step S102.

In step S104, the control unit 230 determines whether or not a communication abnormality has occurred. Here, the control unit 230 obtains the peak strength of the electrical signal acquired in step S103 (the electrical signal in the frequency band corresponding to the SAW sensor 212 determined to be directly below the reader antenna 220), and if the peak strength is less than a predetermined threshold, it determines that a communication abnormality has occurred.

If it is determined that there is a communication abnormality (S104, Yes), the process of the control unit 230 proceeds to step S105. In step S105, the control unit 230 issues an alarm. Then, the process of the control unit 100 proceeds to step S108. In step S108, the control unit 100 controls the drive unit 23 to stop the rotation of the susceptor (rotary table 2), and ends the process.

If it is determined that there is no communication abnormality (S104: No), the control unit 230 proceeds to step S106.

In step S106, the control unit 230 performs a temperature calculation process for the SAW sensor 212. Here, the temperature calculation unit 234 of the control unit 230 calculates the measured temperature of the SAW sensor 212 determined to be directly below the reader antenna 220 in step S102 based on the electrical signal captured in step S103 (the electrical signal in the frequency band corresponding to the SAW sensor 212 determined to be directly below the reader antenna 220). Here, the temperature calculation unit 234 finds the peak frequency that is a peak in the electrical signal in the frequency band corresponding to the SAW sensor 212 determined to be directly below the reader antenna 220, and calculates the measured temperature based on the peak frequency.

In step S107, the control unit 230 determines whether the temperature measurement process has ended. If the temperature measurement process has not ended (S107: No), the control unit 230 returns to step S102 and repeats the temperature measurement process.

When the temperature measurement process is completed (S107, Yes), the process of the control unit 230 proceeds to step S108. In step S108, the control unit 100 controls the drive unit 23 to stop the rotation of the susceptor (rotary table 2) and terminates the process.

Figure 6 is a time chart showing an example of the temperature measurement process. In Figure 6, the horizontal axis indicates the passage of time, and shows an example of the signal from the position sensor 25, the communication acquisition process in step S103, and the strength of the communication signal between the reader antenna 220 and the SAW sensor 212.

The substrate-type temperature sensor 210 is placed in a recess 24 of the turntable 2 that rotates inside the chamber 1. Therefore, when the SAW sensor 212 is placed at a position away from the reader antenna 220, the strength of the communication signal between the reader antenna 220 and the SAW sensor 212 is weak. Then, as the turntable 2 rotates, the strength of the communication signal increases around the time when the SAW sensor 212 is directly below the reader antenna 220.

The control unit 230 performs a communication acquisition process after a predetermined time has elapsed since the position sensor 25 detected a signal (in other words, after the turntable 2, which rotates at a constant speed, has rotated a predetermined angle). In other words, the control unit 230 acquires an electrical signal from the SAW sensor 212 at a timing synchronized with the rotation of the turntable 2, and calculates the temperature. This makes it possible to stabilize the temperature measurement by increasing the communication strength between the reader antenna 220 and the SAW sensor 212 and stabilizing the communication.

In addition, by using the SAW sensor 212 as the temperature sensor, the substrate-type temperature sensor 210 placed in the chamber 1 does not require a battery. This makes it possible to measure the temperature even in processes where the temperature inside the chamber 1 becomes high (e.g., 150°C or higher).

In addition, by using the SAW sensor 212 as a temperature sensor, the temperature detection accuracy can be improved compared to, for example, using a radiation thermometer.

It should be noted that multiple openings 18, dielectric windows 18a and 18b, and reader antennas 220 may be provided. This allows multiple temperature measurements to be taken during one rotation of the turntable 2. Therefore, even if the rotation speed of the turntable 2 is low, the time interval between temperature measurements can be shortened.

In addition, in step S103, the timing for acquiring the electrical signal has been described as the timing when it is determined that the SAW sensor 212 is directly below the reader antenna 220, but this is not limited to this. The timing for acquiring the electrical signal may be before or after the timing when the SAW sensor 212 is directly below the reader antenna 220. This makes it possible to increase the communication strength between the reader antenna 220 and the SAW sensor 212 and stabilize the communication, thereby stabilizing the temperature measurement.

The above describes the temperature measurement method using the temperature measurement device 200, but the present disclosure is not limited to the above-mentioned embodiments, and various modifications and improvements are possible within the scope of the gist of the present disclosure described in the claims.

REFERENCE SIGNS LIST 1 chamber 2 rotary table 18 openings 18a, 18b dielectric window 22 rotary shaft 23 driving section 24 recess 25 position sensor 100 control section 200 temperature measuring device 210 substrate-type temperature sensor 211 substrate-shaped member 212 SAW sensor 220 reader antenna 230 control section 231 transmitting section 232 receiving section 233 sensor position estimating section 234 temperature calculating section P1 first processing area P2 second processing area D separation area

Claims (4)

A temperature measuring device for a substrate processing apparatus including a chamber and a rotary table provided within the chamber and having a plurality of substrate mounting portions on an upper surface thereof, the temperature measuring device measuring a temperature of a substrate shaped member mounted on the substrate mounting portions when the substrate processing apparatus is not performing the substrate processing, the temperature measuring device comprising:
one or more substrate-type temperature sensors each having a plurality of SAW sensors for detecting the temperature of the substrate-shaped member and the substrate-shaped member, the substrate-type temperature sensors being placed on the substrate placement portion of the rotating table;
An antenna for transmitting and receiving electrical signals;
a transmitter that transmits an electrical signal in a predetermined frequency band including a resonant frequency of the SAW sensor via the antenna;
a receiving unit that receives an electrical signal transmitted from the SAW sensor via the antenna;
a temperature calculation unit that calculates a detected temperature of the SAW sensor based on the electrical signal received by the receiving unit;
a position sensor that outputs a signal when the rotary table is located at a predetermined home position;
The transmission unit is
While the rotary table is rotating, an electrical signal in the frequency band is transmitted regardless of a rotational position of the rotary table;
The receiving unit is
After a predetermined time has elapsed since the position sensor output a signal, the electrical signal received by the antenna is acquired;
The temperature calculation unit is
calculating a detected temperature of the SAW sensor based on the electrical signal received by the receiving unit;
Temperature measuring device. the antenna is disposed outside the chamber and receives an electrical signal transmitted from the SAW sensor through an opening in the chamber ;
2. The temperature measuring device of claim 1. The SAW sensor receives the electrical signal transmitted by the antenna and transmits an electrical signal including temperature information detected by the SAW sensor.
The temperature measuring device according to claim 1 or 2. A temperature measurement method for a temperature measurement device in a substrate processing apparatus including a chamber and a turntable provided within the chamber and having a plurality of substrate mounting portions on an upper surface thereof, the temperature measurement device measuring a temperature of a substrate shaped member mounted on the substrate mounting portions when the substrate processing apparatus is not performing the substrate processing, the method comprising:
The temperature measuring device is
a transmitting section that transmits an electrical signal in a predetermined frequency band including a resonant frequency of the SAW sensor via the antenna ; a receiving section that receives the electrical signal transmitted from the SAW sensor via the antenna; a temperature calculating section that calculates a detected temperature of the SAW sensor based on the electrical signal received by the receiving section ; and a position sensor that outputs a signal when the turntable is positioned at a predetermined home position ,
the transmitting unit transmits an electrical signal in the frequency band regardless of a rotational position of the turntable while the turntable rotates,
the receiving unit receives the electrical signal received by the antenna after a predetermined time has elapsed since the position sensor output a signal,
The temperature calculation unit calculates a detected temperature of the SAW sensor based on the electrical signal received by the receiving unit.
Temperature measurement methods.

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