TW202036198A - Temperature control device, temperature control method, and inspection apparatus - Google Patents

Abstract

A temperature control device for controlling a temperature of an object, the temperature control device includes a heater having a heating source configured to heat the object, a cooler having a cooling source configured to cool the object; and a temperature controller configured to control the heating source and the cooling source. The temperature controller includes a sliding mode controller configured to supply power to the heating source as an operation amount, a cooling mode controller configured to supply power to the cooling source as an operation amount, and a switching controller configured to determine whether an output of the sliding mode controller will be output to the heating source as a first operation amount, or an output of the cooling mode controller will be used as a second operation amount, based on a nonlinear term value of the output of the sliding mode controller.

Description

Temperature control device, temperature control method and inspection device

This disclosure relates to a temperature control device, a temperature control method, and an inspection device.

In the semiconductor manufacturing process, a large number of electronic components with a predetermined circuit pattern are formed on a semiconductor wafer (hereinafter only referred to as wafer). The formed electronic components will be inspected for electrical characteristics, etc., to distinguish good products from defective products. The inspection of electronic components is performed, for example, using an inspection device in a wafer state before each electronic component is divided.

The electronic component inspection device is equipped with: a probe card with a large number of needle-shaped probes; a mounting table on which a wafer is placed; and a test table (refer to Patent Document 1). This inspection device allows the probes of the probe card to contact the electrode contacts or solder bumps that are set corresponding to the electrodes of the electronic components, so that the signals from the electronic components are transmitted to the test bench to inspect the electrical of the electronic components characteristic. In addition, when inspecting the electrical characteristics of electronic components, the inspection device of Patent Document 1 has a temperature control that controls the temperature of the mounting table by means of a refrigerant flow channel or a heater in the mounting table in order to reproduce the actual installation environment of the electronic component. Device.

In addition, Patent Document 2 describes the use of cooling water and a thermoelectric conversion module, and a sliding mode control to perform temperature control of the wafer.

[Prior Technical Literature]

[Patent Literature]

Patent Document 1: Japanese Patent Application Laid-Open No. 10-135315

Patent Document 2: Japanese Patent Application Publication No. 2002-318602

The present disclosure provides a temperature control device, a temperature control method, and an inspection device that can control the temperature of a temperature control object with good controllability even if interference occurs.

The temperature control device related to one aspect of the present disclosure is a temperature control device that performs temperature control of the temperature control object; it has a heating mechanism that has a heating source that can heat the temperature control object; a cooling mechanism that can cool the object The cooling source of the temperature control object; and the temperature controller, which controls the heating source and the cooling source; the temperature controller takes the temperature measurement of the temperature control object as the control object, and has: a sliding mode ) The controller uses the power input to the heating source as the operating variable; the cooling mode controller uses the power input to the cooling source as the operating variable; and the switching controller is the output of the sliding mode controller In the linear and nonlinear terms, the value of the nonlinear term is used to determine whether to directly output the output of the sliding mode controller as the first operating variable to the heating source, or not to use the sliding mode controller Output, and use the output of the cooling mode controller as the second operation amount.

The temperature control device related to another aspect of the present disclosure is a temperature control device that performs temperature control of the temperature control object; it has a heating mechanism that has a heating source that can heat the temperature control object; a cooling mechanism that can cool The cooling source of the temperature control object; and a temperature controller that controls the heating source and the cooling source; the temperature controller takes the temperature measurement of the temperature control object as the control object, and has: a sliding mode (sliding mode) mode) controller, which regards the power input to the heating source as the operating quantity; the cooling mode controller, which regards the power input to the cooling source as the operating quantity; and the switching controller, which is the sliding mode controller In the output linear term and nonlinear term, the value of the nonlinear term is used to determine whether to directly use the output of the sliding mode controller as the first operation The output to the heating source or the addition of the output of the sliding mode controller and the output of the cooling mode controller is used as the second operation amount.

According to the present disclosure, it is possible to provide a temperature control device, a temperature control method, and an inspection device that can control the temperature of the temperature control object with good controllability even if interference occurs.

1: Inspection device

2: Inspection Department

3: Loading department

4: Test bench

10: Pedestal

12: Probe card

12a: Probe

13: Interface

15: Control Department

20: Temperature control device

30, 30’: Temperature controller

31a: Temperature sensor

32a: refrigerant flow path

40: heating mechanism

41: LED

50: Cooling mechanism

52: Cooling piping

53: Variable flow valve

54: high speed valve

60: Temperature measurement circuit

71: Sliding Mode Controller

72: Cooling mode controller

73, 73’: Switch controller

74: Factory model

77: adder

D: Electronic components (temperature measurement object)

W: Wafer

Fig. 1 is a perspective view showing a schematic configuration of an inspection device related to the first embodiment.

Fig. 2 is a front view showing a part of the inspection device of Fig. 1 in section.

Fig. 3 is a plan view schematically showing the structure of a wafer as a substrate of an object to be inspected.

Fig. 4 is a cross-sectional view schematically showing the structure of the upper part of the pedestal and the temperature control device.

Fig. 5 is a plan view schematically showing the structure of the heating mechanism.

Fig. 6 is a diagram schematically showing the structure of a circuit for temperature measurement of an electronic component.

Fig. 7 is a diagram for explaining the sliding mode control.

Fig. 8 is a block diagram showing the control block of the temperature controller in the inspection device according to the first embodiment.

FIG. 9 is a block diagram showing the interior of the sliding mode controller in the temperature controller of FIG. 8.

Fig. 10 is a block diagram showing the nonlinear input part of the sliding mode controller of Fig. 9.

FIG. 11 is a block diagram showing the composition of the cooling mode controller and the switching controller in the temperature controller of FIG. 8 and the reception and transmission of these signals.

Figure 12 shows the block diagram inside the factory model.

Fig. 13 is a block diagram showing the control block of the temperature controller in the inspection device according to the second embodiment.

FIG. 14 is a block diagram showing the internals of the cooling mode controller and the switching controller in the temperature controller of FIG. 13 and the reception of these signals.

FIG. 15 is a diagram of the simulation result when the heat interference is 150W when the temperature control of the chip is performed by sliding mode control.

Fig. 16 is a graph of the simulation result when the heat interference is 300W when the temperature control of the chip is performed by sliding mode control.

FIG. 17 is a diagram of the simulation result when the heat interference is 450W when the temperature control of the chip is performed by sliding mode control.

FIG. 18 is a graph of simulation results when the heat interference is 150W when the temperature control of the chip is performed by the control of the first embodiment.

FIG. 19 is a graph of the simulation result when the heat interference is 300 W when the temperature control of the chip is performed by the control of the first embodiment.

FIG. 20 is a graph of simulation results when the heat interference is 450W when the temperature control of the chip is performed by the control of the first embodiment.

FIG. 21 is a graph of simulation results when the heat interference is 150W when the temperature control of the chip is performed by the control of the second embodiment.

Fig. 22 is a graph of simulation results when the heat interference is 300W when the temperature control of the chip is performed by the control of the second embodiment.

FIG. 23 is a graph of the simulation result when the heat interference is 450W when the temperature control of the chip is performed by the control of the second embodiment.

Fig. 24 is a diagram showing an enlarged simulation result of the first embodiment when the heat interference is 150W.

FIG. 25 is a diagram showing an enlarged simulation result of the second embodiment when the heat interference is 150W.

Fig. 26 is a diagram showing an enlarged simulation result of the first embodiment when the heat interference is 300W.

Fig. 27 is a diagram showing an enlarged simulation result of the second embodiment when the heat interference is 300W.

Fig. 28 is a diagram showing an enlarged simulation result of the first embodiment when the heat interference is 450W.

Fig. 29 is a diagram showing an enlarged simulation result of the second embodiment when the heat interference is 450W.

Hereinafter, the embodiment will be described with reference to the attached drawings.

<First Embodiment>

First, the first embodiment will be described.

Fig. 1 is a perspective view showing a schematic configuration of an inspection device related to the first embodiment, and Fig. 2 is a front view showing a part of the inspection device of Fig. 1 in cross section.

As shown in FIGS. 1 and 2, the inspection apparatus 1 is a person who inspects the electrical characteristics of a plurality of electronic components formed on a wafer W as a substrate of an object to be inspected, and includes: an inspection section 2; a loading section 3; and Test bench 4.

The inspection unit 2 has a frame 11 with a cavity inside, and the frame 11 has a pedestal 10 on which the wafer W to be inspected can be sucked and fixed. In addition, the pedestal 10 is configured to use a moving mechanism (not shown) Move freely in the horizontal and vertical directions. Below the base 10 is a temperature control device 20 for the temperature of the console base. The temperature control device 20 will be described in detail later.

A probe card 12 is arranged above the pedestal 10 in the inspection part 2 so as to face the pedestal 10. The probe card 12 has a plurality of probes 12a as contacts. In addition, the probe card 12 is connected to the test bench 4 through the interface 13. When each probe 12a is in contact with the electrode of each electronic component of the wafer W, each probe 12a supplies power from the test station 4 to the electronic component through the interface 13, or transmits a signal from the electronic component to the electronic component through the interface 13. Test bench 4 passes.

The loading unit 3 has a frame 14 in which a FOUP (not shown) that is easy to transport in which the wafer W is accommodated is arranged. In addition, the loading unit 3 has a transport mechanism (not shown), and the wafer W stored in the FOUP is taken out by the transport mechanism and transported to the pedestal 10 of the inspection unit 2. In addition, the wafer W on the pedestal 10 after the inspection of the electrical characteristics is completed is transported by the transport device, and stored in the FOUP.

In addition, the frame 14 of the loading section 3 is provided with a control section 15 which performs various controls such as temperature control of electronic components of the inspection object; and a potential difference measurement unit 16 which measures the potential difference generation circuit in each electronic component ( (Illustration omitted) potential difference. The potential difference generating circuit is, for example, a diode, a transistor, or a reactance. The potential difference measuring unit 16 is connected to the interface 13 to obtain the potential difference between the two probes 12a that will contact the two electrodes corresponding to the potential difference generating circuit, and transmit the obtained potential difference to the control unit 15. The connection structure of each probe 12a in the interface 13 and the wiring from the potential difference measuring unit 16 will be described in detail later.

The control unit 15 has a temperature controller 30 included in the temperature control device 20, and the temperature controller 30 controls the following heating mechanism and cooling mechanism. In addition, the control unit 15 and the potential difference measurement unit 16 may be installed in the housing 11 of the inspection unit 2, and the potential difference measurement device 16 may also be installed in the probe card 12.

The frame 11 of the inspection unit 2 is provided with a user interface surface 18 that constitutes a part of the control unit 15. The user interface surface 18 is used to display information to the user or allow the user to input a pointer, and is composed of, for example, an input unit such as a touch panel or a keyboard and a display unit such as a liquid crystal display.

The test stand 4 has a test board (not shown) that reproduces a part of the circuit configuration of the motherboard on which electronic components are mounted. The test board is connected to a test computer 17 which judges the quality of the electronic component based on the signal from the electronic component. The test bench 4 can be constructed by replacing the above-mentioned test board to reproduce a plurality of motherboard circuits.

In addition, the probe card 12, the interface 13, and the test stand 4 constitute an inspection mechanism.

When checking the electrical characteristics of electronic components, the test computer 17 transmits data to the test board connected to the electronic components through the probes 12a. Then, the test computer 17 judges whether the transmitted data is correctly processed by the test board based on the electrical signal from the test board.

As shown in FIG. 3, the wafer W as the substrate of the object to be inspected has a plurality of electronic components D, which are separated by predetermined intervals on the surface by applying etching or wiring processing to a substantially disc-shaped silicon substrate Be formed. An electrode E is formed on the surface of the electronic component D, and the electrode E is electrically connected to the circuit component inside the electronic component D. By applying a voltage to the electrode E, a current can flow through the circuit elements inside each electronic element D.

Next, the pedestal 10 and the temperature control device 20 will be described using FIG. 4. 4 is a cross-sectional view schematically showing the upper structure of the pedestal 10 and the temperature control device 20.

As shown in FIG. 4, the pedestal 10 has a bottomed member 32 and a cover member 31. The cover member 31 is installed on the bottomed member 32 through the sealing ring 33. The wafer W is sucked and held on the cover member 31.

The cover member 31 is formed in a disc shape, and is made of, for example, SiC. The thermal conductivity and Young's rate of SiC will be higher. Also, relative to the absorption efficiency of the light from the LED41 of the heating mechanism 40 below It will also be higher, and the cover member 31 can be heated efficiently by the light from the heating mechanism 40. In addition, the SiC system can be formed by sintering after being formed on a green sheet, which can reduce the amount of processing.

The upper surface of the cover member 31 is formed with suction holes (not shown) for sucking the wafer W. In addition, the cover member 31 is embedded with a plurality of temperature sensors 31a at positions separated from each other in a plan view.

The bottomed member 32 is formed in a circular plate shape having approximately the same diameter as the cover member 31, and is composed of a transparent material with respect to the wavelength of the light from the LED below. The upper portion of the bottomed member 32 is formed with a groove for circulating the refrigerant, and the groove is covered by the cover member 31 to form a refrigerant flow passage 32a. That is, the pedestal 10 has a refrigerant flow passage 32a inside.

The temperature control device 20 has a heating mechanism 40, a cooling mechanism 50 and a temperature controller 30. The temperature control device 20 is controlled by heating by the heating mechanism 40 and cooling by the cooling mechanism 50 to stabilize the temperature of the electronic component D of the inspection object formed by the wafer W on the pedestal 10 at the target temperature.

The heating mechanism 40 is configured as a light irradiation mechanism, and the cover member 31 of the pedestal 10 is irradiated with light to heat the cover member 31 to heat the wafer W to heat the electronic components D formed on the wafer W.

The heating mechanism 40 is arranged so as to face the surface opposite to the wafer W mounting surface of the pedestal 10, that is, the lower surface of the bottomed member 32. The heating mechanism 40 has a plurality of LEDs 41 that irradiate light toward the wafer W as a heating source. Specifically, the heating mechanism 40 has a structure in which a plurality of LED units 43 after a plurality of LEDs 41 are unitized are mounted on the surface of the base 42. As shown in FIG. 5, the LED unit 43 of the heating mechanism 40 has: a unit 43a, which is arranged in a manner corresponding to the electronic component D (refer to FIG. 3), and is square in plan view; and a unit 43b, which is arranged On its periphery and looking down It is non-square under observation. With the units 43a and 43b covering substantially the entire surface of the base 42, the LED 41 of the LED unit 43 can irradiate at least the whole part of the cover member 31 where the wafer W is mounted.

Each LED 41 emits near-infrared light, for example. The light emitted from the LED 41 (hereinafter, also referred to as "LED light") will penetrate the bottomed member 32 of the pedestal 10 formed by the light-transmitting member. The refrigerant circulating in the refrigerant flow passage 32a is made of a material that allows light from the LED 41 to pass through. The light passing through the bottomed member 32 penetrates the refrigerant circulating in the refrigerant flow passage 32a and enters the cover member 31. When the light from the LED 41 is near-infrared light, polycarbonate, quartz, polyvinyl chloride, acrylic resin or glass can be used as the light transmitting member constituting the bottomed member 32. These materials can be easily processed or shaped.

In the heating mechanism 40, the LED light incident on the cover member 31 of the pedestal 10 on which the wafer W is placed is controlled by the LED unit 43 as a unit. Therefore, the heating mechanism 40 can only irradiate the LED light to any position of the cover member 31, or the intensity of the irradiated light can be different from other positions at any position.

The cooling mechanism 50 includes a cooling unit 51, a refrigerant pipe 52, a variable flow valve 53, and a high-speed valve 54. The cooling unit 51 stores the refrigerant and controls the temperature of the refrigerant to a predetermined temperature. As the refrigerant system, for example, liquid water that can penetrate the light irradiated from the LED 41 can be used. The refrigerant pipe 52 is connected to the supply port 32 b and the discharge port 32 c provided on the side of the bottomed member 32, and is connected to the cooling unit 51. The refrigerant in the cooling unit 51 is circulated in the refrigerant flow passage 32a through the refrigerant pipe 52 by a pump (not shown) installed in the refrigerant pipe 52. The variable flow valve 53 is provided on the downstream side of the cooling unit 51 of the refrigerant piping 52, and the high-speed valve 54 is provided on the downstream side of the cooling unit 51 in the branch pipe 52a that divides the variable flow valve 53. The variable flow valve 53 can set the flow rate and supply the refrigerant at a fixed amount of the set flow rate. In addition, the high-speed valve 54 opens and closes (opens, closes) at a high speed based on a nonlinear gain term in the sliding control described below, and can supply/stop the refrigerant flowing through the branch pipe 52a at a high speed.

Based on the measurement result of the temperature of the electronic component D, the temperature controller 30 uses the heating mechanism 40 and the cooling mechanism 50 to control the temperature of the base in such a way that the temperature of the electronic component D becomes a predetermined temperature.

The temperature of the electronic component D is measured by the temperature measurement circuit 60. FIG. 6 is a diagram schematically showing the configuration of the temperature measurement circuit 60 of the electronic component D.

As shown in FIG. 6, each probe 12a is connected to the test bench 4 through a plurality of wires 61 arranged on the interface 13. The two wirings 61 connecting the two probes 12a of the potential difference generating circuit (for example, a diode) in the electronic component D to the two electrodes E of the test stand 4 are respectively provided with a relay 62. In addition, the relay 62 may also be connected to the wiring 63 of the potential difference measurement unit 16.

That is, each relay 62 can switch the potential of each electrode E to any one of the test stand 4 and the potential difference measurement unit 16 for transmission. For example, when the electrical characteristics of the electronic component D are inspected, after the actual installation voltage is applied to each electrode E, the potential of each electrode E is transmitted to the potential difference measuring unit 16 at a predetermined time. It is known that in the above-mentioned potential difference generating circuit, the potential difference generated when a predetermined current flows varies depending on the temperature. Therefore, the temperature of the electronic component D can be measured immediately during the inspection based on the potential difference of the potential difference generating circuit of the electronic component D, that is, the potential difference between the two electrodes E (probe 12a) of the potential difference generating circuit.

That is, the temperature measurement circuit 60 is composed of a potential difference generation circuit in the electronic component D, two probes 12a contacted by its two electrodes, two wirings 61, relay 62, wiring 63, and potential difference measurement connected to them. The unit 16 constitutes.

In addition, the method for measuring the temperature of the electronic component D is not limited to the above, and may be other methods.

The temperature controller 30 is based on the temperature measurement result of the above-mentioned general electronic component D, and is controlled by the sliding mode that uses the power (current value output) input to the LED 41 as the heating source as the operating quantity, and the direction as the cooling source. The input power of the high-speed valve (that is, the opening and closing signal of the high-speed valve) is used as the cooling mode control of the operating quantity for temperature control.

The sliding mode control is a control method of switching control on the upper and lower switching phase planes by the way of the preset switching phase plane (switching surface) in the state space. In the case that the initial state of the control object is outside the switching phase plane, the state of the control object will arrive in a limited time and be constrained in the switching phase plane (arrival mode). After the state of the control object reaches the switching phase plane, it will slide the state on the switching phase plane and converge towards the target value (sliding mode). The control input u of the sliding mode control is the sum of the linear term (linear control operation quantity) u1 and the non-linear term (non-linear control operation quantity) un1, and can be expressed by the following mathematical formula

u=-(SB) ^-1 SAx-K(SB) ^-1 . sgn(σ)=-(SB) ^-1 {SAx+K. sgn(σ)}

σ=Sx

SAx is a linear term, K. sgn(σ) is a nonlinear term. A and B are the determinants of the state equation, and S and K are the control parameters. The function sgn is a discontinuous function, and sgn(σ) is the switching function of the sliding mode. The switching phase plane can be designed in the framework of linear control. In the sliding mode, the switching phase plane uses a nonlinear term to go back and forth between the area II and the area I shown in Figure 7 in a very short time and switch the phase plane. Move up. That is, in the sliding mode, the linear term (linear control operation amount) minimizes the control error in the switching phase plane of the state of the control system, and the nonlinear term makes the control when there are modeling errors or uncertain disturbances. The state of the system is towards the switching phase plane.

FIG. 8 is a diagram showing the control block of the temperature controller 30. The temperature controller 30 has a sliding mode controller 17, a cooling mode controller 72, a switching controller 73 and a factory model 74.

The slide mode controller 71 outputs the power input to the LED 41 of the heating mechanism 40 (output as a current value) as an operation amount, and performs temperature control. In the sliding mode controller 71, as shown in FIG. 9, the temperature detection signal x is input, and the linear term (linear gain term) and the nonlinear term (nonlinear gain term) generated in the nonlinear input part 75 To form the control input u. As shown in FIG. 10, the nonlinear input unit 75 generates a nonlinear input (non-linear term): un1 by switching functions σ, SWgain: k, and SWita: η. un1 is expressed by the following mathematical formula.

un1=-k. σ/(｜σ｜+η)

η is the vibration suppression item. Due to the non-linear input (non-linear term): the switching frequency of the un1 system is infinite, so the state quantity will vibrate (high frequency vibration) near the switching phase plane. Therefore, η is used to suppress chattering and smooth the input.

FIG. 11 is a block diagram showing the inside of the cooling mode controller 72 and the switching controller 73.

The cooling mode controller 72 performs cooling control by using the power input to the high-speed valve 54 as the cooling source (the opening/closing signal of the high-speed valve 54) as the operation amount. In this way, the amount of refrigerant supplied to the refrigerant flow passage 32a of the pedestal 10 is controlled to control the temperature of the electronic component D. The output of the cooling mode controller 72 is calculated by the heat absorption model based on the refrigerant flow rate and the heat absorption coefficient. Although the endothermic coefficient is represented as -0.4 in FIG. 11, this is just an example, and its value can be changed according to the electronic component D and the like.

The switching controller 73 uses the value of the non-linear term un1 of the sliding mode controller as the switching signal. That is, the switching controller 73 uses the value of the non-linear term un1 to determine whether to directly use the output of the sliding mode controller 71 (control output), or not to use the output of the sliding mode controller 71 to control the cooling mode The output of the device 72 is used as the second operation amount.

The so-called direct use of the output (control input) of the sliding mode controller 71 refers to outputting the output of the sliding mode controller 71 as the first operation quantity to the LED 41 as the heating source.

The use of the output of the cooling mode controller 72 as the second operation amount means that the output of the high-speed valve which is the cooling source of the cooling mode controller 72 is used as the second operation amount.

Specifically, when the value of the non-linear term un1 is positive (one side of the switching phase plane; area I in Fig. 7), the switching controller 73 will directly use the output of the sliding mode controller 71 as the first operation variable. To output to LED41. In addition, when the value of the non-linear term un1 is negative (the other side of the switching phase plane; area II in Fig. 7), the output of the high-speed valve that is the cooling source of the cooling mode controller 72 (the high-speed valve The open/close signal) is used as the second operation quantity. The opening and closing time of the high-speed valve is at a high speed of 0.1sec or less. The high-speed valve 54 can be opened and closed following the high-speed switching of the non-linear term un1, and the temperature can be controlled with high controllability.

The plant model 74 is a physical model of the electronic component D (the pedestal 10) that is the temperature control object, and is shown in FIG. 12. Then, the signal output from the switching controller 73 is input to the factory model 74, and the factory model 74 undergoes necessary calculations to obtain the control signal.

The temperature control of the electronic component D is performed by the temperature controller 30 while using the variable flow valve 53 of the cooling mechanism 50 to make the refrigerant flow through the refrigerant flow passage 32a at a fixed flow rate to absorb heat. That is, the temperature controller 30 can be used to perform sliding mode control in which the power input to the LED 41 as the heating source is used as the operating quantity, and the power input to the high-speed valve 54 as the cooling source (open/close signal of the high-speed valve) ) Temperature control due to cooling mode control as the operating quantity. At this time, by switching the controller 73, the value of the nonlinear term un1 is used to determine whether to directly use the nonlinear term un1 for sliding mode control, or use the nonlinear term un1 as the opening and closing signal of the high-speed valve 54 Used for cooling mode control. When the value of the non-linear term un1 of the sliding mode control is positive, the temperature control is performed by the sliding mode control that directly uses the power input to the LED 41 as the operating quantity. When the value of the non-linear term un1 of sliding mode control is negative, the non-linear term un1 will be used as the opening of the high-speed valve 54 The closing signal is output, and the sliding mode control of the LED 41 is switched to the cooling mode control. At this time, the temperature control will not use the output of the sliding mode controller 71. By using the cooling mode control, the electronic component D can be cooled in addition to turning off the LED 41. In this way, the temperature controllability of the electronic component D can be ensured under the condition of very large heating interference.

The control unit 15 is composed of a computer, and in addition to the temperature controller 30, it also has a main control unit with a plurality of control functions for controlling each component of the inspection device 1, and the inspection device is controlled by the main control unit The actions of each component. In addition, the control unit has an input device, an output device, a display device, and a memory device. The control of each component caused by the main control unit is implemented by the processing formula of the control program stored in the storage medium (hard disk, optical disc, semiconductor memory, etc.) built into the storage device.

Next, an example of using the inspection device 1 to perform inspection processing on the wafer W will be described. First, the wafer W is taken out from the FOUP of the loading part 3 by the transfer device, and is transferred to the pedestal 10 and placed on it. Next, the pedestal 10 is moved to a predetermined position.

Then, all the LEDs 41 of the heating mechanism 40 are turned on, and based on the information obtained from the temperature sensor 31a of the cover member 31, the light output from the LED 41 is adjusted in such a way that the temperature of the cover member 31 becomes uniform in the plane. The variable flow valve 53 adjusts the flow rate of the refrigerant flowing through the refrigerant flow passage 32a in the pedestal 10.

In this state, the potential difference of the above-mentioned potential difference generating circuit in the electronic component D of the inspection object is obtained by the potential difference measuring unit 16. Then, the above-mentioned potential difference is corrected so that the temperature of the cover member 31 that is uniform in the plane and the temperature of the electronic component D of the inspection object become approximately the same, and the information of the temperature characteristic of the above-mentioned potential difference is corrected.

After that, the pedestal 10 is moved, and the probe 12a provided above the pedestal 10 is brought into contact with the electrode E of the electronic component D of the inspection target of the wafer W. Then, a signal for inspection is input to the probe 12a. With this, the inspection of the electronic component D is started.

In the above inspection, the temperature of the electronic component D to be inspected is measured based on the information of the potential difference generated by the potential difference generating circuit of the electronic component D, and the measured temperature is used as the target temperature, and then the temperature control device 20 performs this Temperature control of electronic component D.

At this time, while the variable flow valve 53 of the cooling mechanism 50 causes the refrigerant to flow through the refrigerant flow passage 32a at a fixed flow rate to absorb heat, the temperature controller 30 performs temperature control. That is, the temperature controller 30 can be used to perform sliding mode control in which the power input to the LED 41 as the heating source is used as the operating quantity, and the power input to the high-speed valve 54 as the cooling source (open/close signal of the high-speed valve) ) Temperature control due to cooling mode control as the operating quantity. At this time, the switching controller 73 will determine whether to directly use the output (control input) of the sliding mode controller 71 or use the non-linear term un1 as the high-speed valve 54 by using the value of the non-linear term un1 as described above. Open and close signals are used to control the cooling mode. Specifically, when the value of the non-linear term un1 of the sliding mode control is positive, the output of the sliding mode controller 71 is directly output to the LED 41 as the first operation variable. On the other hand, when the value of the non-linear term un1 is negative, the non-linear term un1 will be used as the opening and closing signal of the high-speed valve 54 and output to the high-speed valve as the second operating quantity.

In the inspection apparatus of Patent Document 1, when inspecting the electrical characteristics of electronic components, in order to reproduce the actual installation environment of the electronic components, the mounting table is performed by the refrigerant flow channel or heater in the mounting table. temperature control.

On the other hand, in recent years, electronic components have been developing towards higher speed and miniaturization, and the degree of integration will become higher, which will increase the heat generation during operation. Therefore, they are used in electronic components on wafers. During the inspection, there is a risk of generating heat interference and causing bad conditions in the electronic components. However, the above-mentioned Patent Document 1 does not show a method to relieve such heating interference.

Therefore, in this embodiment, after the variable flow valve 53 of the cooling mechanism 50 is used to allow the refrigerant to circulate through the refrigerant supply path 32a of the pedestal 10 at a fixed flow rate to ensure heat absorption, the sliding mode control that can withstand interference is used. , And use the power (current value) input to the LED 41 of the heating mechanism 40 as the operating quantity to control the temperature of the electronic component D.

However, in the sliding mode control in which only the refrigerant flow rate is fixed and the power input to the LED 41 is used as the operation amount, when the heat generation interference becomes very large, even if the LED 41 is turned off, the heat absorption is insufficient. Therefore, there may be cases where the response to interference control becomes slow or the temperature cannot be fully controlled. In addition, although consideration will be given to increasing the refrigerant flow rate to improve heat absorption, in this case, the output of the LED 41 will be insufficient to reach the target temperature. In addition, although it is possible to increase the refrigerant flow rate and use LEDs with a larger maximum output or increase the density of LEDs to suppress the temperature rise of the electronic components, in this case, the cost will increase rather than being realistic.

Therefore, in this embodiment, the variable flow valve 53 of the cooling mechanism 50 allows the refrigerant to flow through the refrigerant flow passage 32a at a fixed flow rate to absorb heat, and the value of the nonlinear term un1 is used to switch control The device 7 switches and implements the sliding mode control using the power input to the LED 41 as the operation amount, and the cooling mode control using the power input to the high-speed valve 54 (the opening and closing signal of the high-speed valve) as the operation amount. That is, when the value of the non-linear term un1 of the sliding mode control is positive, since the influence of the heating interference will be small, the output of the sliding mode controller 71 will be directly used as the first operating quantity and directed to the LED 41 as the heating source Invest. On the other hand, when the value of the non-linear term un1 is negative, the power input to the high-speed valve 54 as the cooling source (the opening/closing signal of the high-speed valve) is used as the second operation amount to perform the cooling mode control. That is, when the sliding mode control is performed, the heating interference of the electronic component D is large and the sliding mode When the non-linear term un1 of the control is negative, the switching controller 73 is used to switch to the cooling mode control. Thereby, in addition to the case where the LED 41 is turned off, the pedestal 10 can be cooled, and the cooling capacity can be enhanced. Therefore, even in the case of very large heating interference, the temperature of the electronic component D can be sufficiently cooled, and the temperature of the electronic component D can be controlled with good controllability. In addition, from the viewpoint of reducing unnecessary time wastage as much as possible, the position of the high-speed valve 54 at this time is preferably as close to the pedestal 10 as possible.

In addition, since the heating mechanism 40 is provided with a plurality of LED units 43 equipped with a plurality of LEDs 41 in a manner corresponding to the plurality of electronic components D, the electronic components D can be individually heated. Therefore, only the electronic component D under inspection can be heated, and heating interference to other electronic components D can be suppressed.

Furthermore, since the high-speed valve 54 is used for cooling mode control, the high-speed valve 54 can be opened and closed following the positive and negative changes of the non-linear term un1 used as the switching signal, and the cooling control can be performed with high accuracy.

In addition, since water can be used as a refrigerant, there is no need to use a chlorofluorocarbon-based refrigerant, and the endothermic property is better than the case of using a chlorofluorocarbon-based refrigerant, and the endothermic heat can be accelerated.

In addition, the inspection of electronic components can be carried out collectively with a plurality of components, and can also be carried out collectively with all electronic components like the collective contact detection used in DRAM and the like. In either case, the temperature of the electronic components of the inspection object can be as described above. The sliding mode control that uses the power of the LED41 as the operating quantity and the cooling mode control that uses the opening and closing of the high-speed valve are used together to achieve good controllability. Temperature control of electronic components.

<Second Embodiment>

Next, the second embodiment will be described.

Although the basic structure of the inspection device of the second embodiment is the same as that of the inspection device 1 of the first embodiment, as shown in FIG. 13 below, only a temperature controller 30' with a different control method is installed instead of The point included in the temperature controller 30 of the temperature control device 20 of the first embodiment is different from the inspection device 1 of the first embodiment.

In the temperature controller 30' of the present embodiment, similar to the temperature controller 30 of the first embodiment, it is based on the temperature measurement result of the electronic component D, and it is based on the power applied to the LED 41 as the heating source ( Current value output) as the control of the sliding mode control of the operating quantity. In addition, the temperature controller 30' is the same as the temperature controller 30 of the first embodiment. In addition to the sliding mode control, the power input to the high-speed valve (that is, the opening and closing signal of the high-speed valve) is also used as an operation The amount of cooling mode control. Among them, the temperature controller 30' of this embodiment is different from the temperature controller 30 by transmitting the control signal to the LED 41 which is the heating source during the cooling mode.

Hereinafter, the temperature controller 30' will be described in detail.

Fig. 13 is a diagram showing the control block of the temperature controller 30'. The temperature controller 30' has a sliding mode controller 71, a cooling mode controller 72, an adder 77, a switching controller 73' and a factory model 74. The basic configurations of the sliding mode controller 71, the cooling mode controller 72, and the factory model 74 are the same as the temperature controller 30 of the first embodiment.

Fig. 14 is a block diagram showing the composition of the cooling mode controller 72, the adder 77 and the switching controller 73' and the reception and transmission of these signals.

As described above, the cooling mode controller 72 performs cooling control by using the power input to the high-speed valve 54 as the cooling source (the opening/closing signal of the high-speed valve 54) as the operation amount. In this way, the amount of refrigerant supplied to the refrigerant flow passage 32a of the pedestal 10 is controlled to control the temperature of the electronic component D. The output of the cooling mode controller 72 is calculated by the heat absorption model based on the refrigerant flow rate and the heat absorption coefficient. Although the endothermic coefficient is represented as -20 in FIG. 14, this is just an example, and the value can vary depending on the electronic component D and the like.

The switching controller 73' is the same as the switching controller 73 of the first embodiment, and uses the value of the non-linear term un1 of the sliding mode controller as the switching signal. Then, the switching controller 73' uses the value of the non-linear term un1 to determine whether to directly use the output of the sliding mode controller 71 or use the second operating value. The switching controller 73' uses the adder 77 to add the output of the sliding mode and the output of the cooling mode controller 72 as the second operation amount. That is, the second operation amount is the sum of the output of the LED 41 from the sliding mode controller 71 as the heating source and the output of the high-speed valve from the cooling mode controller as the cooling source.

The so-called direct use of the output (control input) of the sliding mode controller 71 refers to outputting the output of the sliding mode controller 71 as the first operation quantity to the LED 41 as the heating source.

Specifically, when the value of the non-linear term un1 is positive (one side of the switching phase plane; area I in Figure 7), the switching controller 73' will directly use the output of the sliding mode controller 71 as the first operation The amount is output to LED41. In addition, if the value of the non-linear term un1 is negative (the other side of the switching phase plane; area II in Figure 7), the output of the sliding mode controller 71 and the cooling mode controller 72 will be the high-speed cooling source. The sum of the output of the valve 54 (the opening and closing signal of the high-speed valve) is used as the second operation amount.

As described above, the cooling mode controller 72 opens and closes the high-speed valve 54 operating at a high speed with an opening and closing time of 0.1 sec or less following the high-speed switching caused by the nonlinear term un1. In this way, in addition to turning off the LED 41, the electronic component D can be cooled, and the temperature control of the electronic component D can be ensured in the case of very large heating interference. In addition, as the second operating quantity, not only the output of the high-speed valve of the cooling mode controller 72, but also the output of the sliding mode controller 71 can be added to alleviate the excessive reaction of rapid cooling and obtain good control. Sex.

In this embodiment, similar to the first embodiment, the inspection of the electronic component D is started. Then, in this inspection, the electricity generated by the circuit is generated based on the potential difference of the electronic component D to be inspected. The position difference information is used to measure the temperature of the electronic component D, and the measured temperature is used as the target temperature, and the temperature control device 20 controls the temperature of the electronic component D.

At this time, the variable flow valve 53 of the cooling mechanism 50 causes the refrigerant to flow through the refrigerant flow passage 32a at a fixed flow rate to absorb heat, and the temperature is controlled by the temperature controller 30'. That is, in the temperature controller 30', the switching controller 73' will use the value of the non-linear term un1 to determine whether to directly use the output of the sliding mode controller 71, or to use the output of the sliding mode and the cooling mode control The second operation amount of the addition of the output of the device 72. Specifically, when the value of the non-linear term un1 of the sliding mode control is positive, the output of the sliding mode controller 71 is directly output to the LED 41 as the first operation variable. On the other hand, when the value of the non-linear term un1 is negative, the sum of the output of the sliding mode controller 71 and the output of the high-speed valve that is the cooling source of the cooling mode controller 72 is added as the second operation amount Output.

In the first embodiment described above, the cooling mode controller 72 causes the high-speed valve 54 operating at a high speed with an opening and closing time of 0.1 sec or less to open and close following the high-speed switching caused by the nonlinear term un1. In this way, in addition to turning off the LED 41, the electronic component D can be cooled, and the temperature control of the electronic component D can be ensured in the case of very large heating interference.

However, in the first embodiment, although the controllability is good, when the non-linear term un1 is negative, since only the high-speed valve 54 is operated, the rapid cooling may be overreacted. That is, in order to compensate for the temperature drop of the electronic component D when the high-speed valve 54 is opened by the switching controller 73', the output of the LED 41 needs to be increased, and the time point for the subsequent cooling (high-speed valve To open the time point) earlier. Therefore, when the switching controller 73' is used for control, the amplitude of the current value will increase and the frequency of opening the high-speed valve 54 will increase.

On the other hand, in the present embodiment, the second operation amount in the case where the non-linear term un1 is negative is not only the output of the high-speed valve of the cooling mode controller 72 but also the output of the sliding mode controller 71. In this way, since the control signal is also transmitted to the LED 41 during the operation of the high-speed valve 54, the excessive reaction of rapid cooling can be alleviated. Therefore, in addition to the basic effects of the first embodiment described above, the amplitude of the current value can be reduced, and the opening frequency of the high-speed valve 54 can be reduced, and the effect of smaller amplitude and smoother temperature control can be achieved.

In addition, in the second embodiment, since the basic inspection device has the same configuration as the first embodiment, other effects obtained by the first embodiment can also be obtained in the second embodiment in the same manner.

<Simulation results>

Next, the simulation results will be explained.

Here, we will simulate the temperature controllability of electronic components (chips) with a size of 30mm×40mm formed on a wafer under the influence of thermal interference of 150W, 300W, and 450W.

Figures 15 to 17 are graphs showing the results of the simulation when a constant flow of refrigerant is supplied, the power input to the LED is used as the operating quantity, and the temperature of the chip is controlled by sliding mode control.

As shown in Figure 15, in the case of sliding mode control, although good controllability can be maintained at 150W heat interference, as shown in Figures 16 and 17, it is confirmed that when the heat interference is 300W, 450W, it will be observed When the temperature rises, the temperature cannot be controlled.

Figures 18 to 20 show the first embodiment that uses both sliding mode control using the power input to the LED as the operating quantity and cooling mode control by opening and closing the high-speed valve when the non-linear term un1 is negative. Schema of the simulation result.

As shown in these figures, it was confirmed that the first embodiment of the cooling mode control by using the sliding mode control and the opening and closing of the high-speed valve together can be affected by the heat interference of 150W~450W. Perform good temperature control.

Figures 21 to 23 show the results of the simulation of the second embodiment of the control that adds the output of the sliding mode controller and the output of the cooling mode controller when the non-linear term un1 is negative. figure.

As shown in the figure, it was confirmed that the second embodiment of the control that uses the sliding mode control together and the control that adds the output of the sliding mode controller and the output of the cooling mode controller can interfere with heat generation at any one of 150W to 450W. Under the circumstances, good temperature control can be carried out. In addition, it is found that the amplitude of the current supplied in the second embodiment is smaller in the case of heat disturbance than in the first embodiment.

FIGS. 24 and 25 are diagrams respectively showing the results of the simulation of the first embodiment and the second embodiment when the heat disturbance is 150W, and are displayed in an enlarged manner. From these diagrams, it can be seen that compared with the first embodiment, the amplitude of the current output in the second embodiment is smaller, and the control amplitude is smaller. In addition, the overshoot or undershoot of the control target temperature at the point in time when it is known that the heating disturbance will change rapidly is also smaller in the second embodiment.

FIGS. 26 and 27 are diagrams respectively showing the results of the simulation of the first embodiment and the second embodiment when the heat interference is 300W, and are displayed in an enlarged manner. In addition, FIGS. 28 and 29 are respectively enlarged and displayed diagrams of the simulation results of the first embodiment and the second embodiment when the heat interference is 450W. As can be understood from these figures, even if the interference is as large as 300W or 450W, it will still be the same as when the interference is 150W. Compared with the first embodiment, the amplitude of the current output in the second embodiment will be smaller. And the control amplitude will be smaller. In addition, the overshoot or undershoot of the control target temperature at the point in time when it is known that the heating disturbance will change rapidly is also smaller in the second embodiment.

<Other applicable>

Although the embodiment has been described above, the embodiment disclosed this time should be an illustration in all points and not a limitation. The above-mentioned embodiments can be omitted, replaced, and changed in various forms without going beyond the scope of the attached patent application and the spirit thereof.

For example, in the above-mentioned embodiment, although the case where an LED is used as a heating source has been described, the heating source is not limited to an LED, and other heating sources such as impedance heaters may be used. In addition, although in the above-mentioned embodiment, the electronic component (chip) on the wafer is shown as an example of the temperature control target, the temperature control target may also be a pedestal and is not limited to the electronic component (chip). Moreover, it is not limited to the case where the temperature control device is applied to the inspection device.

30: temperature controller

71: Sliding Mode Controller

72: Cooling mode controller

73: Switch controller

74: Factory model

x: temperature detection signal

u: control input

σ: switching function

Claims (19)

A temperature control device, which is a temperature control device that performs temperature control of a temperature control object; equipped with: The heating mechanism has a heating source that can heat the temperature control object; The cooling mechanism has a cooling source capable of cooling the temperature control object; and The temperature controller controls the heating source and the cooling source; The temperature controller takes the temperature measurement of the temperature control object as the control object, and has: Sliding mode (sliding mode) controller, the power input to the heating source as the operating quantity; The cooling mode controller uses the power input to the cooling source as the operating quantity; and The switching controller is the linear term and the nonlinear term of the output of the sliding mode controller. The value of the nonlinear term determines whether to directly output the output of the sliding mode controller as the first operating variable. The heating source, or the output of the sliding mode controller is not used, and the output of the cooling mode controller is used as the second operation quantity. A temperature control device, which is a temperature control device that performs temperature control of a temperature control object; equipped with: The heating mechanism has a heating source that can heat the temperature control object; The cooling mechanism has a cooling source capable of cooling the temperature control object; and The temperature controller controls the heating source and the cooling source; The temperature controller takes the temperature measurement of the temperature control object as the control object, and has: Sliding mode (sliding mode) controller, the power input to the heating source as the operating quantity; The cooling mode controller uses the power input to the cooling source as the operating quantity; and The switching controller is the linear term and the nonlinear term of the output of the sliding mode controller. The value of the nonlinear term determines whether to directly output the output of the sliding mode controller as the first operating variable. The heating source or the sum of the output of the sliding mode controller and the output of the cooling mode controller is used as the second operation quantity. For example, the temperature control device of item 1 or 2 of the scope of patent application, wherein the switching controller is to use only the sliding mode control when the nonlinear term is in the area on one side of the switching phase plane under sliding mode control If the output of the cooling device is located in the area on the other side of the switching phase plane, the output of the cooling mode controller is used to switch. For example, in the temperature control device of item 3 of the scope of patent application, the area on one side is the area where the value of the nonlinear term is positive, and the area on the other side is the area where the value of the nonlinear term is negative. For example, the temperature control device of any one of items 1 to 4 in the scope of patent application, wherein the heating source is an LED, and the first operation quantity is the current value input to the LED. For example, the temperature control device of any one of items 1 to 5 in the scope of patent application, wherein the cooling mechanism cools the temperature control object by a refrigerant, the cooling source is a high-speed valve that opens and closes the flow path of the refrigerant, and the cooling mode The output of the controller is the opening and closing signal to the high-speed valve. For example, the temperature control device of any one of items 1 to 6 in the scope of the patent application, wherein the cooling mechanism is different from the power input to the cooling source by the cooling mode controller and supplies the refrigerant at a predetermined flow rate to perform the The heat absorption of the temperature control object. For example, the temperature control device of any one of items 1 to 7 in the scope of the patent application, wherein the temperature control object is an electronic component provided on a substrate. A temperature control method is a temperature control method for temperature control of a temperature control object, which takes the temperature measurement of the temperature control object as the control object, and has: The process of sliding mode control (sliding mode) is performed using the power input to the heating source for heating the temperature control object as the operation amount; The process of performing cooling mode control using the power input to the cooling source for cooling the temperature control object as the operation amount; and In the linear term and nonlinear term of the output of the sliding mode control, the value of the nonlinear term is used to determine whether to directly output the output of the sliding mode control as the first operating quantity to the heating source, or not The output of the sliding mode control is used, and the output of the cooling mode control is used as the second operation amount. A temperature control method is a temperature control method for temperature control of a temperature control object, which takes the temperature measurement of the temperature control object as the control object, and has: The process of sliding mode control (sliding mode) is performed using the power input to the heating source for heating the temperature control object as the operation amount; Combining the sliding mode control and the cooling mode control process in which the power input to the cooling source for cooling the temperature control object is used as the operation amount; and In the linear term and nonlinear term of the output of the sliding mode control, the value of the nonlinear term is used to determine whether to directly output the output of the sliding mode control as the first operating quantity to the heating source, or to The addition of the output of the sliding mode control and the output of the cooling mode control is used as a second operation amount. For example, the temperature control method of item 9 or 10 in the scope of the patent application, wherein the determination process is based on the non-linear term in the region on one side of the switching phase plane under sliding mode control, only using If the sliding mode is used for control, and the area on the other side of the switching phase plane is used, the output of the cooling mode control is used for switching. For example, the temperature control method of item 11 in the scope of patent application, wherein the area on one side is the area where the value of the nonlinear term is positive, and the area on the other side is the area where the value of the nonlinear term is negative. For example, the temperature control method of any one of items 9 to 12 in the scope of patent application, wherein the heating source is an LED, and the first operation quantity is the current value input to the LED. For example, the temperature control method of any one of items 9 to 13 in the scope of patent application, wherein the cooling source is a high-speed valve that opens and closes the flow path of the refrigerant that cools the temperature control object, and the operation amount of the cooling mode control is directed toward the High-speed valve opening and closing signal. For example, the temperature control method of any one of items 9 to 14 in the scope of the patent application is different from the operating volume of the cooling mode control and supplies the refrigerant at a predetermined flow rate to absorb heat of the temperature control object. For example, the temperature control method of any one of items 9 to 15 in the scope of the patent application, wherein the temperature control object is an electronic component provided on a substrate. An inspection device with: The pedestal is a substrate on which electronic components are placed; The inspection mechanism is to make the probe electrically contact the electronic component of the substrate set on the pedestal to inspect the electronic component; The temperature measuring part measures the temperature of the electronic component; and Temperature control control device, which controls the temperature of the electronic component; The temperature control device is equipped with: The heating mechanism has a heating source that can heat the electronic component; The cooling mechanism has a cooling source capable of cooling the electronic component; and The temperature controller controls the heating source and the cooling source; The temperature controller takes the temperature measurement of the electronic component as the control object, and has: Sliding mode (sliding mode) controller, the power input to the heating source as the operating quantity; The cooling mode controller uses the power input to the cooling source as the operating quantity; and The switching controller is in the linear term and the nonlinear term of the output of the sliding mode controller. The value of the nonlinear term determines whether to directly output the output of the sliding mode controller as the first operating variable. The heating source or the output of the sliding mode controller is not used, and the output of the cooling mode controller is used as the second operation quantity. An inspection device with: The pedestal is a substrate on which electronic components are placed; The inspection mechanism is to make the probe electrically contact the electronic component of the substrate set on the pedestal to inspect the electronic component; The temperature measuring part measures the temperature of the electronic component; and Temperature control control device, which controls the temperature of the electronic component; The temperature control device is equipped with: The heating mechanism has a heating source that can heat the electronic component; The cooling mechanism has a cooling source capable of cooling the electronic component; and The temperature controller controls the heating source and the cooling source; The temperature controller takes the temperature measurement of the electronic component as the control object, and has: Sliding mode (sliding mode) controller, the power input to the heating source as the operating quantity; The cooling mode controller uses the power input to the cooling source as the operating quantity; and The switching controller is in the linear term and the nonlinear term of the output of the sliding mode controller. The value of the nonlinear term determines whether to directly output the output of the sliding mode controller as the first operating variable. The heating source or the sum of the output of the sliding mode controller and the output of the cooling mode controller is used as the second operation quantity. An inspection device with: The pedestal is a substrate on which electronic components are placed; The inspection mechanism is to make the probe electrically contact the electronic component of the substrate set on the pedestal to inspect the electronic component; The temperature measuring part measures the temperature of the electronic component; and Temperature control control device, which controls the temperature of the electronic component; The temperature control device is equipped with: The heating mechanism has a heating source that can heat the electronic component; The cooling mechanism has a cooling source capable of cooling the electronic component; and The temperature controller controls the heating source and the cooling source; The cooling mechanism has: The refrigerant source is the refrigerant supplied as the cooling source; The first refrigerant piping is connected to the refrigerant source and the pedestal, and the refrigerant is supplied to the pedestal in a predetermined amount from the refrigerant source; The second refrigerant pipe is arranged in parallel with the first refrigerant pipe, and the refrigerant is supplied to the base from the refrigerant source; and The high-speed valve is installed in the second refrigerant pipe, and supplies/stops the refrigerant toward the base.

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