Temperature adjustment method and inspection device for substrate support stand

Abstract

To provide a method and an apparatus for adjusting the temperature of a substrate support table that quickly settles the temperature measured for a next device to be inspected.SOLUTION: A method includes a step of calculating a first operation amount using a feedback control calculation based on a target temperature and a temperature measured by a previous temperature sensor which is a temperature sensor corresponding to a previous inspection target device when an inspection target device is switched, a temperature adjustment mechanism for adjusting the temperature of a wafer mounting surface being provided in common among a plurality of devices, a step of calculating a second operation amount using a feedback control calculation based on a target temperature and a temperature measured by a previous temperature sensor which is a temperature sensor corresponding to a next inspection target device, a step of adding a value obtained by multiplying the first operation amount by a variable α, which is equal to or smaller than 1, and a value obtained by multiplying the second operation amount by 1-α to calculate an operation amount of the temperature adjustment mechanism when the inspection target is switched, and a step of outputting the operation amount of the temperature adjustment mechanism when the inspection target is switched.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a method for adjusting the temperature of a substrate support table and an inspection apparatus.

Background Art

[0002] Patent Document 1 discloses a mounting table for mounting a device to be processed on its upper surface, which includes a top plate having a wafer mounting surface of the device, a heating unit for heating the top plate, and a plurality of temperature sensors for acquiring the temperature of the top plate at a desired measurement position in a plan view.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the technology according to the present disclosure, when inspecting some devices while adjusting the temperature measured by a temperature sensor by feedback control using a common temperature adjustment mechanism among a plurality of devices formed on a substrate, when switching the device to be inspected, the temperature measured by the temperature sensor corresponding to the next device to be inspected is quickly stabilized.

Means for Solving the Problems

[0005] One aspect of the present disclosure is a method for adjusting the temperature of a substrate support base that supports a substrate when inspecting a plurality of devices formed on the substrate. The substrate support base has a wafer placement surface on which the substrate is placed and a plurality of temperature sensors provided along the wafer placement surface. A temperature adjustment mechanism for adjusting the temperature of the wafer placement surface is commonly provided among the plurality of devices. The method includes, when switching the device to be inspected: (A) calculating a first operation amount by feedback control calculation based on the temperature measured by the previous temperature sensor, which is the temperature sensor corresponding to the device that was the inspection target, and the target temperature; (B) calculating a second operation amount by feedback control calculation based on the temperature measured by the next temperature sensor, which is the temperature sensor corresponding to the next device to be inspected, and the target temperature; (C) adding a value obtained by multiplying the variable α, which is 1 or less, by the first operation amount and a value obtained by multiplying 1 - α by the second operation amount to calculate the operation amount of the temperature adjustment mechanism at the time of inspection target switching; and (D) outputting the operation amount of the temperature adjustment mechanism at the time of inspection target switching. The variable α decreases over time, and the rate of decrease decreases over time.

Advantages of the Invention

[0006] According to the present disclosure, when inspecting some devices while adjusting the temperature measured by the temperature sensor by feedback control using a common temperature adjustment mechanism among a plurality of devices formed on a substrate, when switching the device to be inspected, the temperature measured by the temperature sensor corresponding to the next device to be inspected can be quickly stabilized.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0008] In a manufacturing process of a semiconductor device or the like, a device having a predetermined circuit pattern is formed on a substrate such as a semiconductor wafer (hereinafter referred to as "wafer"). The formed devices are inspected for electrical characteristics and the like, and sorted into good products and defective products. The above inspection is performed, for example, in the state of the substrate before being divided into each device, using an inspection apparatus.

[0009] An inspection apparatus called a prober or the like is provided with a substrate support base having a wafer mounting surface on which the substrate on which the device is formed is placed, and a probe card having a large number of probes is attached. At the time of inspection, in the inspection apparatus, an electrical signal is supplied from the tester to the device through the probe in a state where the device and the probe are in contact with each other. Then, based on the electrical signal received by the tester from the device through the probe, it is determined whether the device is a defective product.

[0010] In this type of inspection apparatus, when inspecting the electrical characteristics of a device, for the purpose of simulating the mounting environment of the device, a temperature adjustment mechanism such as a heating mechanism or a cooling mechanism and a temperature sensor are provided. For example, based on the measurement result by the temperature sensor, the temperature of the device formed on the substrate may be adjusted, that is, controlled, by the temperature adjustment mechanism.

[0011] Specifically, the temperature adjustment mechanism adjusts the temperature of the wafer mounting surface of the substrate. In addition, the wafer mounting surface may be divided into a plurality of regions, and the temperature adjustment mechanism may be provided so that the temperature can be adjusted individually for each region. That is, there may be a case where a plurality of temperature adjustment mechanisms are provided. There may also be a case where a plurality of temperature sensors are provided along the wafer placement surface of the substrate. When both a plurality of temperature adjustment mechanisms and a plurality of temperature sensors are provided, during inspection, for example, based on the measurement results of each temperature sensor, each temperature adjustment mechanism operates, and the temperature of the wafer placement surface is adjusted so as to be in-plane uniform at the target temperature.

[0012] The larger the number of temperature sensors and the number of temperature adjustment mechanisms, the higher the temperature adjustment accuracy and the higher the accuracy of device inspection. However, increasing the number of temperature adjustment mechanisms will significantly increase the cost. Not only that, since the thermal influence extends between adjacent regions within the wafer placement surface, the difficulty of temperature control of the control target also increases, and as a result, the temperature controller becomes expensive. On the other hand, a plurality of temperature sensors can be realized with a slight cost increase, for example, by adopting chip sensors.

[0013] Therefore, a configuration may be adopted in which a plurality of temperature sensors are provided on the substrate support table and temperature adjustment is performed by a single temperature adjustment mechanism. That is, a substrate support table may be adopted in which a plurality of temperature sensors are provided and a single temperature adjustment region is set with respect to the wafer placement surface of the substrate.

[0014] By the way, in recent years, in the inspection of logic integrated circuits as devices, due to the progress of high integration and high speed of devices and the increasing heat generation amount, it has become impossible to inspect the devices formed on the substrate all at once. Therefore, it has become the mainstream to perform inspections one by one or for every few devices.

[0015] When performing inspections in this way, when a plurality of temperature sensors are provided on the substrate support table and temperature adjustment is performed by a single temperature adjustment mechanism, based on the temperature measured by the temperature sensor corresponding to the device to be inspected and the target temperature, the operation amount of the temperature adjustment mechanism is calculated by a feedback control operation such as PID control calculation. Then, based on the calculation result, the temperature adjustment mechanism operates, and the temperature measured by the temperature sensor is adjusted to the target temperature. The temperature adjustment by the temperature adjustment mechanism acts not only on the device to be inspected that is generating heat but also on non-inspected devices that are not generating heat. Therefore, during the inspection, the non-inspected devices are at a temperature lower than the target temperature.

[0016] Therefore, when the operation amount of the temperature adjustment mechanism is suddenly switched from being based on the temperature measurement result of the temperature sensor corresponding to the previous device to be inspected to being based on the temperature measurement result of the temperature sensor corresponding to the next device to be inspected during the period from when the power supply to the previous device to be inspected is stopped until the power supply to the next device to be inspected is started, the following phenomena occur. That is, the temperature measured by the temperature sensor corresponding to the next device to be inspected (hereinafter referred to as the "next temperature sensor") does not settle in a short time, and overshoot or undershoot occurs. Especially when the heat generation amount of the device is large, the time until the temperature measured by the next temperature sensor settles becomes long. If the temperature measured by the next temperature sensor does not settle, the inspection of the next device to be inspected cannot be performed, resulting in a deterioration of throughput. If the gain of the feedback control operation is weakened, overshoot and undershoot can be suppressed, but if it is weakened, it takes a long time for the temperature measured by the next temperature sensor to reach the target temperature, and ultimately the throughput deteriorates. These points are prominent in devices with a large heat generation amount.

[0017] Therefore, the technology according to the present disclosure enables the temperature measured by the next temperature sensor to settle earlier when switching the device to be inspected in the case where a plurality of temperature sensors are provided on the substrate support table and temperature adjustment is performed by a single temperature adjustment mechanism.

[0018] Hereinafter, a method for adjusting the temperature of a substrate support table and an inspection apparatus according to the present embodiment will be described with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

[0019] <Inspection apparatus 1> FIG. 1 and FIG. 2 are a perspective view and a front view respectively showing the outline of the configuration of the inspection apparatus 1 according to the present embodiment. In FIG. 2, in order to show the components incorporated in the accommodation chamber and the loader, which will be described later, of the inspection apparatus 1 in FIG. 1, a part thereof is shown in cross section.

[0020] The inspection apparatus 1 inspects the electrical characteristics of devices (not shown) formed on a wafer W as a substrate. A plurality of n devices (n is a natural number of 2 or more) are formed on the wafer W, and the inspection apparatus 1 simultaneously inspects m devices (m is a natural number less than n) at a time. Hereinafter, it is assumed that the number of devices to be inspected at a time is 1. As shown in FIGS. 1 and 2, the inspection apparatus 1 includes an accommodation chamber 2 for accommodating the wafer W during inspection, a loader 3 disposed adjacent to the accommodation chamber 2, and a tester 4 disposed so as to cover the upper part of the accommodation chamber.

[0021] As shown in FIG. 2, the accommodation chamber 2 is a housing with a hollow interior and has a stage 10 as a substrate support table for supporting the wafer W. The stage 10 adsorbs and holds the wafer W so that the position of the wafer W with respect to the stage 10 does not shift. Further, the stage 10 is configured to be movable in the horizontal and vertical directions, and with this configuration, the relative position between the probe card 11 described later and the wafer W can be adjusted so that the electrodes on the surface of the wafer W can be brought into contact with the probes 11a of the probe card 11.

[0022] Above the stage 10 in the accommodation chamber 2, a probe card 11 is disposed so as to face the stage 10. The probe card 11 has probes 11a that make electrical contact with electrodes and the like of the devices formed on the wafer W. Further, the probe card 11 is connected to the tester 4 via the interface 12. Each probe 11a contacts the electrodes of each device formed on the wafer W during the electrical characteristic inspection, supplies the power from the tester 4 to the device via the interface 12, and transmits the signal from the device to the tester 4 via the interface 12.

[0023] The loader 3 takes out the wafer W accommodated in a FOUP (not shown), which is a carrier container, and conveys it to the stage 10 in the accommodation chamber 2. Further, the loader 3 receives the wafer W for which the inspection of the electrical characteristics of the device has been completed from the stage 10 and accommodates it in the FOUP.

[0024] Furthermore, the loader 3 has a control unit 13. The control unit 13 processes computer-executable instructions for causing the inspection apparatus 1 to execute various processes described in the present disclosure. The control unit 13 can be configured to control each element of the inspection apparatus 1 so as to execute the various processes described herein. In one embodiment, part or all of the control unit 13 may be included in the inspection apparatus 1. The control unit 13 may include a processing unit, a storage unit, and a communication interface. The control unit 13 is realized by, for example, a computer. The processing unit can be configured to read a program that provides logic or routines enabling various control operations from the storage unit and perform various control operations by executing the read program. This program may be stored in the storage unit in advance or may be acquired via a medium when necessary. The acquired program is stored in the storage unit and read from the storage unit by the processing unit and executed. The medium may be various computer-readable storage media or may be a communication line connected to the communication interface. The storage media may be temporary or non-temporary. The processing unit may be a CPU (Central Processing Unit). The storage unit may include a RAM (Random Access Memory), a ROM (Read Only Memory), an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface may communicate with the inspection apparatus 1 via a communication line such as a LAN (Local Area Network). Note that the control unit 13 may be provided in the accommodation chamber 2.

[0025] The tester 4 has a test board (not shown) that reproduces a part of the circuit configuration of the motherboard on which the device is mounted. The test board is connected to a tester computer 15 that determines the quality of the device based on signals from the devices formed on the wafer W. In the tester 4, by replacing the test board, it is possible to reproduce the circuit configurations of a plurality of types of motherboards.

[0026] Furthermore, the inspection apparatus 1 includes a user interface unit 16 for displaying information to the user and receiving input instructions from the user. The user interface unit 16 includes, for example, an input unit such as a touch panel or a keyboard, and a display unit such as a liquid crystal display.

[0027] In the inspection apparatus 1 having the above-described components, when inspecting the electrical characteristics of the devices formed on the wafer W, the tester computer 15 transmits data to the test board connected to the devices via the respective probes 11a. Then, the tester computer 15 determines whether the transmitted data has been correctly processed by the test board based on the electrical signals from the test board.

[0028] <Stage 10> Next, the configuration of the stage 10 will be described with reference to FIGS. 3 and 4. FIG. 3 is a cross-sectional view schematically showing the configuration of the stage 10. FIG. 4 is a top view of the stage 10.

[0029] The stage 10 is placed on a moving mechanism (not shown) that moves the stage 10 in the horizontal and vertical directions via a thermal insulation portion 20. The thermal insulation portion 20 is made of, for example, resin, graphite, or a ceramic with low thermal conductivity.

[0030] The stage 10 includes, in order from above, a top plate 110 and a temperature adjustment plate 120.

[0031] The top plate 110 is a member whose upper surface 110a serves as a wafer placement surface on which the wafer W is placed. Hereinafter, the upper surface 110a of the top plate 110, which is also the upper surface of the stage 10, may be referred to as the wafer placement surface 110a. The top plate 110 is formed, for example, in a disc shape. Also, the top plate 110 is thinly formed using a material with high thermal conductivity and Young's modulus so as to have a small heat capacity. By reducing the heat capacity of the top plate 110, for example, the temperature of the top plate 110 can be changed at high speed by heating with a heating plate 121 described later. As the material of the top plate 110, for example, ceramics such as SiC and AlN are used, and when it is necessary to further suppress the production cost, metals such as copper and aluminum are used.

[0032] Also, as shown in FIG. 4, a plurality of temperature sensors 111 are provided along the wafer placement surface 110a of the top plate 110. Specifically, for example, one temperature sensor 111 is provided at the center of the wafer placement surface 110a, and a plurality of temperature sensors 111 are provided at equal intervals on the same circumference centered on the center of the wafer placement surface 110a at the outer peripheral portion of the wafer placement surface 110a. Each temperature sensor 111 measures the temperature of the portion of the wafer placement surface 110a where the temperature sensor 111 is provided.

[0033] The temperature adjustment plate 120 in FIG. 3 constitutes at least a part of a temperature adjustment mechanism TM for adjusting the temperature of the wafer placement surface 110a. The temperature adjustment plate 120 includes a heating plate 121 as a heating mechanism and a cooling plate 122.

[0034] The heating plate 121 is a member that heats the top plate 110, that is, a member that heats the wafer placement surface 110a. The heating plate 121 is formed, for example, in a disk shape. The heating plate 121 is provided, for example, between the top plate 110 and the cooling plate 122. In other words, it is provided at a position closer to the wafer placement surface 110a than the cooling plate 122. This heating plate 121 has a built-in heating element (not shown). The heating element is, for example, a resistance heating element that generates heat by power supply, and the resistance heating element is formed, for example, from tungsten.

[0035] Also, the heating element is not embedded, for example, in the central part of the heating plate 121, but is only embedded in the outer peripheral part of the heating plate 121.

[0036] The cooling plate 122 is provided below the heating plate 121. This cooling plate 122 is a member that cools the top plate 110. The cooling plate 122 is formed, for example, in a disk shape. A flow path 122a through which a refrigerant flows is formed inside the cooling plate 122. A port 123 is connected to the side part of the cooling plate 122. As shown in FIG. 4, the port 123 has a supply port 123a for supplying the refrigerant to the flow path 122a and a discharge port 123b for discharging the refrigerant from the flow path 122a. Note that, for example, a fluorine-based liquid, a liquid such as ethylene glycol, or a gas such as nitrogen can be used as the refrigerant.

[0037] The port 123 is connected to a chiller unit (not shown). The refrigerant whose temperature has been adjusted by the chiller unit is supplied to the flow path 122a through the port 123. A cooling mechanism CM that cools the wafer placement surface 110a is configured by the chiller unit and the cooling plate 122 and the like.

[0038] <Control unit 13> FIG. 5 is a block diagram showing an example of the configuration of the control unit 13 related to the control of the temperature adjustment mechanism TM. As shown in FIG. 5, the control unit 13 includes a temperature acquisition unit 201, an operation amount calculation unit 202, and a temperature control unit 203. Among the above-mentioned units, for example, the temperature acquisition unit 201 and the operation amount calculation unit 202 are realized by a processor such as a CPU reading and executing a program stored in a storage unit (not shown).

[0039] The temperature acquisition unit 201 acquires the temperature of the portion of the wafer mounting surface 110a where the device is located, which is substantially equal to the temperature of the device. Specifically, the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 corresponding to the device to be temperature-acquired. The temperature sensor 111 corresponding to the device to be temperature-acquired is, for example, the temperature sensor closest to the device to be temperature-acquired.

[0040] For example, during the inspection of electrical characteristics, the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 corresponding to the device to be inspected, which is the object of temperature acquisition.

[0041] Also, when switching the device to be inspected, the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 (hereinafter sometimes referred to as "previous temperature sensor 111p") corresponding to the device that was the inspection object. Furthermore, when switching the device to be inspected, the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 (hereinafter sometimes referred to as "next temperature sensor 111n") corresponding to the next device to be inspected.

[0042] Based on the temperature measured by the temperature sensor 111, the operation amount calculation unit 202 calculates the operation amount of the temperature adjustment mechanism TM by feedback control calculation. Specifically, based on the temperature measured by the temperature sensor 111, the operation amount calculation unit 202 calculates the operation amount of the heating plate 121 and the operation amount of the cooling mechanism CM by PID control calculation. The operation amount of the heating plate 121 is, for example, the power supplied to the resistance heating element. Also, the operation amount of the cooling mechanism CM is related to at least one of, for example, the flow rate of the refrigerant and the temperature of the refrigerant. Specifically, it is, for example, the opening degree of the flow rate adjustment valve, etc.

[0043] Note that the gains in the feedback control calculation (specifically, the PID gains) are different for the calculation of the operation amount of the heating plate 121 and for the calculation of the operation amount of the cooling mechanism CM. Also, the gains in the feedback control calculation (specifically, the PID gains) may be common among the temperature sensors 111 or may be different among the temperature sensors 111.

[0044] For example, during the inspection of the electrical characteristics, the operation amount calculation unit 202 calculates the operation amount PVt of the temperature adjustment mechanism TM during the inspection by feedback control calculation (specifically, PID control calculation, etc.) based on the temperature measured by the temperature sensor 111 corresponding to the device under inspection and the target temperature, i.e., the set temperature, and outputs it to the temperature control unit 203. Specifically, during the inspection of the electrical characteristics, the operation amount calculation unit 202 calculates the operation amount PVh of the heating plate 121 during the inspection by PID control calculation based on the temperature measured by the temperature sensor 111 corresponding to the device under inspection and the target temperature, and outputs it to the temperature control unit 203. Similarly, the operation amount calculation unit 202 calculates the operation amount PVc of the cooling mechanism CM during the inspection.

[0045] Also, the operation amount calculation unit 202 includes a first operation amount calculation unit 211, a second operation amount calculation unit 212, and an output operation amount calculation unit 213.

[0046] The first operation amount calculation unit 211 calculates the first operation amount PV1 of the temperature adjustment mechanism TM by feedback control calculation (specifically, PID control calculation, etc.) based on the temperature measured by the previous temperature sensor 111p and the target temperature when switching the device under inspection. Specifically, the first operation amount calculation unit 211 calculates the first operation amount PVh1 of the heating plate 121 by PID control calculation based on the temperature measured by the previous temperature sensor 111p and the target temperature when switching the device under inspection. Similarly, the first operation amount calculation unit 211 calculates the first operation amount PVc1 of the cooling mechanism CM when switching the device under inspection.

[0047] When switching the device under inspection, the second operation amount calculation unit 212 calculates the second operation amount PV2 of the temperature adjustment mechanism TM by means of feedback control calculation (specifically, PID control calculation, etc.) based on the temperature measured by the next temperature sensor 111n and the target temperature. Specifically, when switching the device under inspection, the second operation amount calculation unit 212 calculates the second operation amount PVh2 of the heating plate 121 by means of PID control calculation based on the temperature measured by the next temperature sensor 111n and the target temperature. Similarly, when switching the device under inspection, the second operation amount calculation unit 212 calculates the second operation amount PVc2 of the cooling mechanism CM.

[0048] When switching the device under inspection, the output operation amount calculation unit 213 calculates the operation amount PVs of the temperature adjustment mechanism TM at the time of switching the inspection target by adding the value obtained by multiplying the variable α, which is 1 or less, by the first operation amount PV1 of the temperature adjustment mechanism TM and the value obtained by multiplying 1 - α by the second operation amount PV2 of the temperature adjustment mechanism TM. That is, the output operation amount calculation unit 213 calculates the operation amount PVs of the temperature adjustment mechanism TM at the time of switching the inspection target based on the following formula. PVs = α * PV1+(1 - α) * PV2(=(PV1 - PV2) * α+PV2)

[0049] The variable α decreases over time, and the rate of decrease also decreases over time. Specifically, the variable α decreases exponentially. More specifically, the variable α is represented by the following formula (X). α = e -t / T …(X)

[0050] In formula (X), T is a predetermined time constant. Specifically, the time constant T is determined in advance based on the time allowed at the time of switching the device under inspection, and more specifically, it is determined in advance based on, for example, the allowed index time. Also, in formula (X), t is the elapsed time since the previous inspection ended. Specifically, it is the elapsed time since the energization for inspection of the previous device under inspection ended at the time of switching the device under inspection.

[0051] The variable α may be common among the temperature sensors 111 or may be different among the temperature sensors 111.

[0052] When switching the device under inspection, the operation amount calculation unit 213 for output specifically adds the value obtained by multiplying the variable α, which is 1 or less, by the first operation amount PVh1 of the heating plate 121 and the value obtained by multiplying 1 - α by the second operation amount PVh2 of the heating plate 121 to calculate the operation amount PVhs of the heating plate 121 at the time of switching the device under inspection. Similarly, when switching the device under inspection, the operation amount calculation unit 213 for output calculates the operation amount PVcs of the cooling mechanism CM at the time of switching the device under inspection.

[0053] Also, the operation amount calculation unit 213 for output outputs the operation amount PVs of the temperature adjustment mechanism TM at the time of switching the device under inspection, specifically, the operation amount PVhs of the heating plate 121 and the operation amount PVcs of the cooling mechanism CM at the time of switching the device under inspection, to the temperature control unit 203. That is, in the present embodiment, the operation amount calculation unit 213 for output also serves as an output unit that outputs the operation amount PVs of the temperature adjustment mechanism TM at the time of switching the device under inspection.

[0054] The temperature control unit 203 controls the temperature adjustment mechanism TM based on the input operation amount PVs of the temperature adjustment mechanism TM at the time of switching the device under inspection. Specifically, the temperature control unit 203 controls the heating plate 121 based on the input operation amount PVhs of the heating plate 121 at the time of switching the device under inspection. Also, the temperature control unit 203 controls the cooling mechanism CM based on the input operation amount PVcs of the cooling mechanism CM at the time of switching the device under inspection.

[0055] <Inspection Flow> Next, an example of the inspection flow by the inspection apparatus 1 will be described. First, the wafer W is taken out from the FOUP of the loader 3, conveyed to the stage 10, and placed thereon. Next, the stage 10 is moved so that the probe 11a provided above the stage 10 comes into contact with the electrodes of the devices to be inspected among the plurality of devices formed on the wafer W. Then, the input of the inspection signal to the probe 11a is started. That is, the energization of the device to be inspected is started. Thereby, the inspection of the electrical characteristics of the device to be inspected is started. At the end of the inspection of the electrical characteristics, the energization of the device that was the inspection target is stopped, and the probe 11a is separated from the electrodes of the device. Then, the same process is performed for the next device to be inspected on the wafer W. Thereafter, the above-described steps are repeated until the inspection of the electrical characteristics is completed for all the devices.

[0056] <Temperature control during inspection> During the above-described inspection of the electrical characteristics, it is required that the temperature of the device to be inspected reaches a desired temperature. Therefore, for example, during the inspection of the electrical characteristics, the temperature acquisition unit 201 acquires the temperature of the portion of the wafer mounting surface 110a where the device to be inspected is located, which is substantially equal to the temperature of the device to be inspected. Specifically, the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 corresponding to the device to be inspected. In addition, the operation amount calculation unit 202 calculates the deviation δ between the temperature acquired by the temperature acquisition unit 201 and the desired temperature, that is, the target temperature, and based on the deviation δ, calculates the operation amounts PVh and PVc of the heating plate 121 and the cooling mechanism CM during the inspection by PID control calculation, and outputs them to the temperature control unit 203. Then, the temperature control unit 203 controls the heating plate 121 and the cooling mechanism CM based on the operation amounts PVh and PVc of the heating plate 121 and the cooling mechanism CM during the inspection. Thereby, the temperature of the device to be inspected is made constant at the target temperature.

[0057] <Temperature control when switching the inspection target> When switching the device to be inspected, temperature control different from that during inspection is performed.

[0058] Specifically, when switching the device to be inspected, first, the power supply to the device that was the inspection target is stopped, and the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 corresponding to the device that was the inspection target, that is, the previous temperature sensor 111p. In addition, the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 corresponding to the next device to be inspected, that is, the next temperature sensor 111n.

[0059] Furthermore, the first operation amount calculation unit 211 calculates the deviation δp between the temperature measured by the previous temperature sensor 111p and the target temperature, and the second operation amount calculation unit 212 calculates the deviation δn between the temperature measured by the next temperature sensor 111n and the target temperature. Also, the first operation amount calculation unit 211 calculates the first operation amounts PVh1 and PVc1 of the heating plate 121 and the cooling mechanism CM by PID control calculation based on the deviation δp. At the same time, the second operation amount calculation unit 212 calculates the second operation amounts PVh2 and PVc2 of the heating plate 121 and the cooling mechanism CM by PID control calculation based on the deviation δn.

[0060] Furthermore, the output operation amount calculation unit 213 adds the value obtained by multiplying the first operation amount PVh1 of the heating plate 121 by the variable α and the value obtained by multiplying the second operation amount PVh2 of the heating plate 121 by 1 - α to calculate the operation amount PVhs of the heating plate 121 at the time of inspection target switching, and outputs it to the temperature control unit 203. Also, the output operation amount calculation unit 213 adds the value obtained by multiplying the first operation amount PVc1 of the cooling mechanism CM by the variable α and the value obtained by multiplying the second operation amount PVc2 of the cooling mechanism CM by 1 - α to calculate the operation amount PVcs of the cooling mechanism CM at the time of inspection target switching, and outputs it to the temperature control unit 203.

[0061] Then, the temperature control unit 203 controls the heating plate 121 and the cooling mechanism CM based on the operation amounts PVhs and PVcs of the heating plate 121 and the cooling mechanism CM at the time of inspection target switching.

[0062] When a first predetermined time elapses after the power supply to the device to be inspected is stopped, the control of the heating plate 121 and the cooling mechanism CM by the temperature control unit 203 based on the operation amounts PVhs and PVcs of the heating plate 121 and the cooling mechanism CM at the time of inspection object switching is stopped. Instead, the control of the heating plate 121 and the cooling mechanism CM by the temperature control unit 203 based on the second operation amounts PVh2 and PVc2 of the heating plate 121 and the cooling mechanism CM is started. When changing the operation amount used for the control of the heating plate 121 and the cooling mechanism CM, the integral value related to the integral control operation used for calculating the second operation amounts PVh2 and PVc2 may be held without being reset. That is, when changing the above operation amount, the integral value held by an integrator (not shown) used for calculating the second operation amounts PVh2 and PVc2 may not be reset.

[0063] Also, when a first predetermined time elapses after the power supply to the device to be inspected is stopped, and the temperature measured by the next temperature sensor 111n continues to fall within a range close to the target temperature (for example, target temperature ±1°) for a second predetermined time, the power supply to the next device to be inspected can be started. That is, the electrical characteristic inspection of the next device to be inspected can be started.

[0064] Note that the gain in the PID control operation is the same when switching the device to be inspected and during the inspection.

[0065] <Main operational effects> As described above, in the present embodiment, the temperature adjustment mechanism TM for adjusting the temperature of the wafer placement surface 110a of the stage 10 is provided in common among a plurality of devices, and a plurality of temperature sensors 111 are provided along the wafer placement surface 110a. Further, in the present embodiment, when switching the device to be inspected, the first operation amount calculation unit 211 calculates the first operation amount PV1 of the temperature adjustment mechanism TM by feedback control calculation based on the temperature measured by the previous temperature sensor 111p and the target temperature. At the same time, the second operation amount calculation unit 212 calculates the second operation amount PV2 of the temperature adjustment mechanism TM by feedback control calculation based on the temperature measured by the next temperature sensor 111n and the target temperature. Then, the output operation amount calculation unit 213 adds the value obtained by multiplying α (α is a variable less than or equal to 1, which decreases over time and the rate of decrease also decreases over time) to the first operation amount PV1 of the temperature adjustment mechanism TM and the value obtained by multiplying 1 - α to the second operation amount PV2 of the temperature adjustment mechanism TM to calculate the operation amount PVs of the temperature adjustment mechanism TM at the time of switching the inspection target. The calculated operation amount PVs is output to the temperature control unit 203 and used for controlling the temperature adjustment mechanism TM.

[0066] The device that was the inspection target corresponding to the previous temperature sensor 111n generates heat by energization in the previous inspection, but since the temperature is adjusted, the deviation δp between the temperature measured by the previous temperature sensor 111p and the target temperature is small and substantially zero. Therefore, the first operation amount PV1 of the temperature adjustment mechanism TM is also small. On the other hand, the next device to be inspected corresponding to the next temperature sensor 111n was not energized and did not generate heat in the previous inspection because it was not the inspection target, but since the same temperature adjustment as that of the device to be inspected that generates heat by energization is performed, the deviation δn between the temperature measured by the next temperature sensor 111n and the target temperature is relatively large. Therefore, the second operation amount PV2 of the temperature adjustment mechanism TM also becomes large. In particular, immediately after switching the inspection target (specifically, immediately after starting the temperature control at the time of switching), the deviation δn is large, and the second operation amount PV2 of the temperature adjustment mechanism TM also becomes large.

[0067] Therefore, unlike the present embodiment, when switching the device to be inspected, if the second manipulated variable PV2 of the temperature adjustment mechanism TM is continuously used for controlling the temperature adjustment mechanism TM from the beginning of the switching, the manipulated variable of the temperature adjustment mechanism TM becomes large at the initial stage of the switching, and the change in the temperature measured by the next temperature sensor 111n also becomes large. As a result, overshoot or undershoot occurs in the temperature measured by the next temperature sensor 111n. That is, the settling time of the temperature measured by the next temperature sensor 111n becomes long.

[0068] In contrast, in the present embodiment, when switching the device to be inspected, instead of the second manipulated variable PV2 of the temperature adjustment mechanism TM, the manipulated variable PVs of the temperature adjustment mechanism TM at the time of switching the inspection target is used for controlling the temperature adjustment mechanism TM. The manipulated variable PVs of the temperature adjustment mechanism TM at the time of switching the inspection target is equal to, or approximately equal to, the first manipulated variable PV1 of the temperature adjustment mechanism TM at the initial stage of the switching. Also, the first manipulated variable PV1 of the temperature adjustment mechanism TM is small as described above. That is, in the present embodiment, the manipulated variable of the temperature adjustment mechanism TM is small at the initial stage of switching the inspection target. Therefore, according to the present embodiment, the change in the temperature measured by the next temperature sensor 111n is also small at the initial stage of switching the inspection target. As a result, overshoot or undershoot is less likely to occur in the temperature measured by the next temperature sensor 111n. Also, even if the gain in the feedback control calculation is increased so that the temperature measured by the next temperature sensor 111n reaches the target temperature earlier, the manipulated variable PVs of the temperature adjustment mechanism TM at the time of switching the inspection target as described above is small at the initial stage of switching the inspection target. Therefore, in the present embodiment, the gain in the feedback control calculation can be increased. Therefore, according to the present embodiment, when switching the device to be inspected, the temperature measured by the next temperature sensor 111n can reach the target temperature earlier while suppressing overshoot and undershoot. Therefore, according to the present embodiment, when a temperature adjustment mechanism TM for adjusting the temperature of the wafer mounting surface 110a of the stage 10 is commonly provided among a plurality of devices and a plurality of temperature sensors 111 are provided along the wafer mounting surface 110a, the temperature measured by the next temperature sensor 111p can be quickly stabilized.

[0069] The gain in the feedback control calculation may be common among the temperature sensors 111 as described above. In the present embodiment, even if a strong common gain in the feedback control calculation is adopted, regardless of which of the plurality of temperature sensors 111 is the next temperature sensor 111n, overshoot or undershoot in the temperature measured by the next temperature sensor 111n can be suppressed. When the gain in the feedback control calculation is common among the temperature sensors 111, the setting of the gain is easy.

[0070] Also, if an appropriate variable α (specifically, a time constant T) is set based on the time allowed at the time of switching the device to be inspected (specifically, for example, the allowed index time), the temperature measured by the next temperature sensor 111p can be stabilized within the allowed time.

[0071] Furthermore, as described above, when changing the operation amounts used for controlling the heating plate 121 and the cooling mechanism CM from the operation amounts PVhs and PVcs at the time of inspection object switching to the second operation amounts PVh2 and PVc2, the integral value related to the integral control calculation used for calculating the second operation amounts PVh2 and PVc2 may be held without being reset. Thereby, it is possible to prevent overshoot or undershoot from occurring in the temperature measured by the next temperature sensor 111n by resetting the integral value. That is, thereby, it is possible to prevent the time until the temperature measured by the next temperature sensor 111p is stabilized from being prolonged by resetting the integral value.

[0072] <Another example of the control unit 1> FIG. 6 is a block diagram showing another example 1 of the configuration related to the control of the temperature adjustment mechanism TM of the control unit. In the operation amount calculation unit 202 of the control unit 13 in FIG. 5, the output operation amount calculation unit 213 also served as an output unit. In contrast, the operation amount calculation unit 202A of the control unit 13A in FIG. 6 has an output unit 221 separately from the output operation amount calculation unit 213A.

[0073] The output operation amount calculation unit 213A is different from the output operation amount calculation unit 213 in FIG. 5 only in that it outputs the calculated operation amount PVs of the temperature adjustment mechanism at the time of switching the inspection target to the output unit 221. The output unit 221 performs base clip processing on the operation amount PVs of the temperature adjustment mechanism TM at the time of switching the inspection target so as not to be within the dead zone, and outputs the base clip processed operation amount PVs' to the temperature control unit 203. Specifically, the output unit 221 performs base clip processing on the operation amount PVs of the temperature adjustment mechanism TM at the time of switching the inspection target so that the operation amount PVs' output from the output unit 221 is not within a predetermined dead zone. The base clip processing is a process of setting the operation amount to the upper limit value of the dead zone when the operation amount is within the dead zone.

[0074] Thereby, even when there is a dead zone that does not accompany a temperature change of the temperature adjustment target in the operation amount output from the output unit 221 and input to the temperature control unit 203, the temperature of the temperature adjustment target can be appropriately adjusted. Specifically, it is as follows. That is, for example, when the operation amount of the cooling mechanism CM as the operation amount of the temperature adjustment mechanism relates to the opening degree of the flow rate adjustment valve provided in the cooling mechanism CM, there may be a dead zone where the opening degree does not change even when the operation amount changes. In this case, by performing the base clip processing as described above, it is possible to suppress the opening degree from rapidly increasing and the temperature measured by the next temperature sensor 111n from rapidly changing.

[0075] Further, the manipulated variable PVs' after the output unit 221 performs base clip processing may have hysteresis. That is, the output unit 221 may perform base clip processing on the manipulated variable PVs of the temperature adjustment mechanism TM at the time of switching the inspection target so that the manipulated variable output from the output unit 221 has hysteresis. Further, the output unit 221 may perform further calculation on the manipulated variable after the base clip processing so that the manipulated variable output from the output unit 221 has hysteresis.

[0076] As a result, when the temperature change occurring in the temperature adjustment target is different even for the same manipulated variable when the manipulated variable output from the output unit 221 increases and decreases and input to the temperature control unit 203, this can be compensated. Specifically, for example, when the manipulated variable of the cooling mechanism CM as the manipulated variable of the temperature adjustment mechanism relates to the opening degree of the flow rate adjustment valve provided in the cooling mechanism CM, this can be compensated when the opening degree is different when opening and closing the opening degree of the flow rate adjustment valve even for the same manipulated variable. As a result, unnecessary hunting can be suppressed.

[0077] <Another example of the control unit 2> FIG. 7 is a block diagram showing another example 2 of the configuration related to the control of the temperature adjustment mechanism TM of the control unit. The manipulated variable calculation unit 202B of the control unit 13B in FIG. 7 has a waste time compensation unit 231 in addition to each unit of the manipulated variable calculation unit 202 of the control unit 13 in FIG. 5.

[0078] The waste time compensation unit 231 calculates a compensation amount corresponding to the waste time Tw included in the transmission system from the input of the manipulated variable of the temperature adjustment mechanism TM to the temperature adjustment mechanism TM to the output of the temperature measurement result by the temperature sensor 111 by the Smith method.

[0079] Specifically, the idle time compensation unit 231 calculates the difference (T11 - T12) between the temperature T11 corresponding to the operation amount in the transfer model of the heating plate 121 without considering the idle time and the temperature T12 corresponding to the operation amount in the transfer model of the heating plate 121 considering the idle time, as the idle time compensation amount δh applied to the heating plate 121. Further, the idle time compensation unit 231 calculates the difference (T21 - T22) between the temperature T21 corresponding to the operation amount in the transfer model of the cooling mechanism CM without considering the idle time and the temperature T22 corresponding to the operation amount in the transfer model of the cooling mechanism CM considering the idle time, as the idle time compensation amount δc applied to the cooling mechanism CM.

[0080] For example, the idle time and transfer model applied to the heating plate 121 are different between the temperature sensors 111. Specifically, when the heating element is embedded only in the outer peripheral portion of the heating plate 121, the idle time and transfer model applied to the heating plate 121 are different between the temperature sensor 111 provided at the central portion of the wafer mounting surface 110a and the temperature sensor 111 provided at the outer peripheral portion. Also, for example, the idle time and the idle time compensation amount δc applied to the cooling mechanism CM are common between the temperature sensors 111. Specifically, when the operation amount of the cooling mechanism CM relates to the temperature of the refrigerant, there is an idle time applied to the cooling mechanism CM, and the idle time and the idle time compensation amount δc are common between the temperature sensors 111.

[0081] In this example, the first operation amount calculation unit 211A and the second operation amount calculation unit 212A calculate the first operation amount PV1 and the second operation amount PV2 of the temperature adjustment mechanism TM based on the compensation amounts calculated by the idle time compensation unit 231, respectively.

[0082] Specifically, the first operation amount calculation unit 211A calculates the first operation amount PVh1 of the heating plate 121 based on the idle time compensation amount δh applied to the heating plate 121 corresponding to the idle time of the previous temperature sensor 111p. More specifically, the first operation amount calculation unit 211A adds the waste time compensation amount δh applied to the heating plate 121 corresponding to the waste time of the previous temperature sensor 111p to the deviation δp between the temperature measured by the previous temperature sensor 111p and the target temperature, and calculates the corrected deviation δp'. Then, the first operation amount calculation unit 211A calculates the first operation amount PVh1 of the heating plate 121 by PID control calculation based on the corrected deviation δp'.

[0083] Specifically, the second operation amount calculation unit 212A calculates the second operation amount PVh2 of the heating plate 121 based on the waste time compensation amount δh applied to the heating plate 121 corresponding to the waste time of the subsequent temperature sensor 111n. More specifically, the first operation amount calculation unit 211A adds the waste time compensation amount δh applied to the heating plate 121 corresponding to the waste time of the subsequent temperature sensor 111n to the deviation δn between the temperature measured by the subsequent temperature sensor 111n and the target temperature, and calculates the corrected deviation δn'. Then, the second operation amount calculation unit 212A calculates the second operation amount PVh2 of the heating plate 121 by PID control calculation based on the corrected deviation δn'.

[0084] In addition, the first operation amount calculation unit 211A calculates the first operation amount PVc1 of the cooling mechanism CM based on the waste time compensation amount δc applied to the cooling mechanism CM corresponding to the waste time common to the temperature sensors 111. Specifically, the first operation amount calculation unit 211A adds the waste time compensation amount δc applied to the cooling mechanism CM corresponding to the waste time common to the temperature sensors 111 to the deviation δp between the temperature measured by the previous temperature sensor 111p and the target temperature, and calculates the corrected deviation δp'. Then, the first operation amount calculation unit 211A calculates the first operation amount PVc1 of the cooling mechanism CM by PID control calculation based on the corrected deviation δp'.

[0085] Furthermore, the second operation amount calculation unit 212A calculates the second operation amount PVc2 of the cooling mechanism CM based on the waste time compensation amount δc applied to the cooling mechanism CM corresponding to the waste time common to the temperature sensors 111. Specifically, the second operation amount calculation unit 212A adds a waste time compensation amount δc applied to the cooling mechanism CM corresponding to the common waste time among the temperature sensors 111 to the deviation δn between the temperature measured by the subsequent temperature sensor 111n and the target temperature, and calculates a corrected deviation δn'. Then, the second operation amount calculation unit 212A calculates a second operation amount PVh2 of the cooling mechanism CM by PID control calculation based on the corrected deviation δn'.

[0086] As described above, by the first operation amount calculation unit 211A and the second operation amount calculation unit 212A respectively calculating the first operation amount PV1 and the second operation amount PV2 of the temperature adjustment mechanism TM based on the compensation amount calculated by the waste time compensation unit 231, it is possible to correct for the temporal dead zone.

[0087] Specifically, even when there is a waste time from when the operation amount of the heating plate 121 is input to the temperature control unit 203 until the output of the temperature measurement result by the temperature sensor 111, it is possible to more reliably adjust the temperature measured by the next temperature sensor 111n. Further, even when the waste time differs among the temperature sensors 111, regardless of the position of the next temperature sensor 111n, it is possible to adjust the temperature measured by the next temperature sensor 111n.

[0088] Also, even when there is a waste time from when the operation amount of the cooling mechanism CM is input to the temperature control unit 203 until the output of the temperature measurement result by the temperature sensor 111, it is possible to more reliably adjust the temperature measured by the next temperature sensor 111n.

[0089] The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The above embodiments may be omitted, replaced, or changed in various forms without departing from the scope and gist of the appended claims. For example, the constituent elements of the above embodiments can be arbitrarily combined. From such an arbitrary combination, the actions and effects of each constituent element involved in the combination can be naturally obtained, and other actions and other effects that are obvious to those skilled in the art from the description in this specification can also be obtained.

[0090] Moreover, the effects described in this specification are merely illustrative or exemplary and not limiting. That is, the technology according to the present disclosure may exhibit other effects that are apparent to those skilled in the art from the description of this specification, together with or instead of the above effects.

[0091] Note that the following configuration examples also fall within the technical scope of the present disclosure. (1) A method for adjusting the temperature of a substrate support table that supports a substrate when inspecting a plurality of devices formed on the substrate, wherein the substrate support table has a wafer placement surface on which the substrate is placed and a plurality of temperature sensors provided along the wafer placement surface, a temperature adjustment mechanism for adjusting the temperature of the wafer placement surface is commonly provided among the plurality of devices, the method includes: when switching the device to be inspected, (A) calculating a first operation amount by feedback control calculation based on the temperature measured by the previous temperature sensor, which is the temperature sensor corresponding to the device that was the inspection target, and the target temperature; (B) calculating a second operation amount by feedback control calculation based on the temperature measured by the next temperature sensor, which is the temperature sensor corresponding to the next device to be inspected, and the target temperature; (C) adding a value obtained by multiplying the first operation amount by a variable α that is 1 or less and a value obtained by multiplying the second operation amount by 1 - α to calculate the operation amount of the temperature adjustment mechanism at the time of switching the inspection target; (D) outputting the operation amount of the temperature adjustment mechanism at the time of switching the inspection target, wherein the variable α decreases over time and the rate of decrease decreases over time, a method for adjusting the temperature of a substrate support table. (2) The method for adjusting the temperature of a substrate support table according to (1), wherein the variable α decreases exponentially. (3) The method for adjusting the temperature of a substrate support table according to (1), wherein the variable α is represented based on the following formula (X). α = e -t / T …(X) T: Predetermined time constant t: Elapsed time since the previous inspection ended (4) The step (D) is the method for adjusting the temperature of the substrate support table according to any one of (1) to (3) above, which performs base clip processing on the operation amount of the temperature adjustment mechanism at the time of switching the inspection target so as not to be within the dead zone, and outputs the operation amount subjected to the base clip processing. (5) The method for adjusting the temperature of the substrate support table according to (4) above, wherein the operation amount subjected to the base clip processing has hysteresis. (6) (E) The method further includes a step of calculating a compensation amount corresponding to the dead time included in the transmission system from the input of the operation amount to the temperature adjustment mechanism to the output of the temperature measurement result by the temperature sensor by the Smith method. In the step (A) and the step (B) respectively, based on the compensation amount, the first operation amount and the second operation amount are calculated, which is the method for adjusting the temperature of the substrate support table according to any one of (1) to (5) above. (7) In the step (E), a compensation amount corresponding to the dead time for the previous temperature sensor and a compensation amount corresponding to the dead time for the next temperature sensor are calculated. In the step (A), based on the compensation amount corresponding to the dead time for the previous temperature sensor, the first operation amount is calculated. In the step (B), based on the compensation amount corresponding to the dead time for the next temperature sensor, the second operation amount is calculated, which is the method for adjusting the temperature of the substrate support table according to (6) above. (8) When switching the operation amount used for controlling the temperature adjustment mechanism from the operation amount of the temperature adjustment mechanism at the time of switching the inspection target to the second operation amount, the integral value related to the integral control operation used for calculating the second operation amount is held without being reset, which is the method for adjusting the temperature of the substrate support table according to any one of (1) to (7) above. (9) An inspection apparatus for inspecting a plurality of devices formed on a substrate, comprising a substrate support table having a wafer placement surface on which the substrate is placed and a plurality of temperature sensors provided along the wafer placement surface. A temperature adjustment mechanism for adjusting the temperature of the wafer mounting surface is provided in common among the plurality of devices. When switching the device to be inspected, based on the temperature measured by the previous temperature sensor, which is the temperature sensor corresponding to the device that was the inspection target, and the target temperature, a first operation amount calculation unit calculates a first operation amount by feedback control calculation. When switching the device to be inspected, based on the temperature measured by the next temperature sensor, which is the temperature sensor corresponding to the next device to be inspected, and the target temperature, a second operation amount calculation unit calculates a second operation amount by feedback control calculation. An output operation amount calculation unit adds the value obtained by multiplying the variable α, which is 1 or less, by the first operation amount and the value obtained by multiplying 1 - α by the second operation amount to calculate the operation amount of the temperature adjustment mechanism at the time of inspection target switching. The inspection apparatus further includes an output unit that outputs the operation amount of the temperature adjustment mechanism at the time of inspection target switching. The variable α decreases over time, and the inspection apparatus in which the decrease rate decreases over time. (10) The inspection apparatus according to (9), wherein the variable α decreases exponentially. (11) The inspection apparatus according to (9), wherein the variable α is represented based on the following formula (X). α = e -t / T …(X) T: Predetermined time constant t: Elapsed time since the previous inspection ended (12) The inspection apparatus according to any one of (9) to (11), wherein the output unit performs base clip processing on the operation amount of the temperature adjustment mechanism at the time of inspection target switching so as not to be within the dead zone, and outputs the operation amount subjected to the base clip processing. (13) The inspection apparatus according to (12), wherein the operation amount subjected to the base clip processing has hysteresis. (14) The inspection apparatus further includes a dead time compensation unit that calculates a compensation amount corresponding to the dead time included in the transmission system from the input of the operation amount to the temperature adjustment mechanism to the output of the temperature measurement result by the temperature sensor by the Smith method. The first operation amount calculation unit and the second operation amount calculation unit each calculate the first operation amount and the second operation amount based on the compensation amount, and the inspection apparatus according to any one of (9) to (13) above. (15) The idle time compensation unit calculates a compensation amount corresponding to the idle time for the previous temperature sensor and a compensation amount corresponding to the idle time for the next temperature sensor. The first operation amount calculation unit calculates the first operation amount based on the compensation amount corresponding to the idle time for the previous temperature sensor. The second operation amount calculation unit calculates the second operation amount based on the compensation amount corresponding to the idle time for the next temperature sensor, and the inspection apparatus according to (14) above. (16) When the operation amount used for controlling the temperature adjustment mechanism is switched from the operation amount of the temperature adjustment mechanism at the time of switching the inspection target to the second operation amount, the integral value related to the integral control operation used for calculating the second operation amount is held without being reset, and the inspection apparatus according to any one of (9) to (15) above.

Explanation of Reference Numerals

[0092] 1 Inspection apparatus 10 Stage 110a Upper surface (wafer placement surface) 111 Temperature sensor 211, 211A First operation amount calculation unit 212, 212A Second operation amount calculation unit 213, 213A Output operation amount calculation unit 221 Output unit TM Temperature adjustment mechanism W Wafer

Claims

1. A method for adjusting the temperature of a substrate support base that supports a substrate when inspecting a plurality of devices formed on the substrate, the method comprising: The substrate support base has a wafer placement surface on which the substrate is placed, and a plurality of temperature sensors provided along the wafer placement surface. A temperature adjustment mechanism for adjusting the temperature of the wafer placement surface is commonly provided among the plurality of devices. The method includes: When switching the device to be inspected, (A) calculating a first operation amount by feedback control calculation based on the temperature measured by a previous temperature sensor, which is the temperature sensor corresponding to the device that was the inspection target, and a target temperature; (B) calculating a second operation amount by feedback control calculation based on the temperature measured by a next temperature sensor, which is the temperature sensor corresponding to the next device to be inspected, and a target temperature; (C) adding a value obtained by multiplying the first operation amount by a variable α that is 1 or less and a value obtained by multiplying the second operation amount by 1 - α to calculate an operation amount of the temperature adjustment mechanism at the time of switching the inspection target; (D) outputting the operation amount of the temperature adjustment mechanism at the time of switching the inspection target, wherein the variable α decreases over time and the rate of decrease decreases over time. A method for adjusting the temperature of a substrate support base.

2. The method for adjusting the temperature of a substrate support base according to claim 1, wherein the variable α decreases exponentially.

3. The method for adjusting the temperature of a substrate support base according to claim 1, wherein the variable α is represented based on the following formula (X). α = e -ｔ／Ｔ …(X) T: A predetermined time constant t: The elapsed time since the previous inspection ended

4. In the step (D), the operation amount of the temperature adjustment mechanism at the time of switching the inspection target is subjected to base clip processing so as not to be within the dead zone, and the operation amount subjected to the base clip processing is output. The method for adjusting the temperature of a substrate support base according to any one of claims 1 to 3.

5. The method for adjusting the temperature of a substrate support base according to claim 4, wherein the operation amount subjected to the base clip processing has hysteresis.

6. The method further includes (E) calculating a compensation amount corresponding to the dead time included in the transmission system from the input of the operation amount to the temperature adjustment mechanism to the output of the temperature measurement result by the temperature sensor by the Smith method, and in the steps (A) and (B), the first operation amount and the second operation amount are calculated based on the compensation amount, respectively. The method for adjusting the temperature of a substrate support base according to any one of claims 1 to 3.

7. In the step (E), a compensation amount corresponding to the waste time for the previous temperature sensor and a compensation amount corresponding to the waste time for the next temperature sensor are calculated, in the step (A), the first operation amount is calculated based on the compensation amount corresponding to the waste time for the previous temperature sensor, in the step (B), the second operation amount is calculated based on the compensation amount corresponding to the waste time for the next temperature sensor. The temperature adjustment method for a substrate support table according to claim 6.

8. When switching the operation amount used for controlling the temperature adjustment mechanism from the operation amount of the temperature adjustment mechanism at the time of switching the inspection target to the second operation amount, the integral value related to the integral control calculation used for calculating the second operation amount is held without resetting. The temperature adjustment method for a substrate support table according to any one of claims 1 to 3.

9. An inspection apparatus for inspecting a plurality of devices formed on a substrate, comprising a substrate support table having a wafer placement surface on which the substrate is placed and a plurality of temperature sensors provided along the wafer placement surface, commonly including a temperature adjustment mechanism for adjusting the temperature of the wafer placement surface among the plurality of devices, a first operation amount calculation unit that calculates a first operation amount by feedback control calculation based on the temperature measured by the previous temperature sensor, which is the temperature sensor corresponding to the device that was the inspection target, and the target temperature when switching the inspection target device; a second operation amount calculation unit that calculates a second operation amount by feedback control calculation based on the temperature measured by the next temperature sensor, which is the temperature sensor corresponding to the next inspection target device, and the target temperature when switching the inspection target device; an output operation amount calculation unit that adds a value obtained by multiplying the first operation amount by a variable α that is 1 or less and a value obtained by multiplying the second operation amount by 1 - α to calculate the operation amount of the temperature adjustment mechanism at the time of switching the inspection target; further comprising an output unit that outputs the operation amount of the temperature adjustment mechanism at the time of switching the inspection target, wherein the variable α decreases over time and the rate of decrease decreases over time. The inspection apparatus.

10. The variable α decreases exponentially. The inspection apparatus according to claim 9.

11. The variable α is represented based on the following formula (X). The inspection apparatus according to claim 9. α = e -t / T... (X) T: A predetermined time constant t: The elapsed time since the previous inspection ended

12. The output unit performs a base clip process on the operation amount of the temperature adjustment mechanism at the time of switching the inspection target so as not to enter the dead zone, and outputs the operation amount subjected to the base clip process. The inspection apparatus according to any one of claims 9 to 11.

13. The operation amount subjected to the base clip process has hysteresis. The inspection apparatus according to claim 12.

14. The inspection apparatus further includes a dead time compensation unit that calculates a compensation amount corresponding to the dead time included in the transmission system from the input of the operation amount to the temperature adjustment mechanism to the output of the temperature measurement result by the temperature sensor by the Smith method. The first operation amount calculation unit and the second operation amount calculation unit each calculate the first operation amount and the second operation amount based on the compensation amount. The inspection apparatus according to any one of claims 9 to 11.

15. The dead time compensation unit calculates a compensation amount corresponding to the dead time for the previous temperature sensor and a compensation amount corresponding to the dead time for the next temperature sensor. The first operation amount calculation unit calculates the first operation amount based on the compensation amount corresponding to the dead time for the previous temperature sensor. The second operation amount calculation unit calculates the second operation amount based on the compensation amount corresponding to the dead time for the next temperature sensor. The inspection apparatus according to claim 14.

16. When the operation amount used for controlling the temperature adjustment mechanism is switched from the operation amount of the temperature adjustment mechanism at the time of switching the inspection target to the second operation amount, the integral value related to the integral control operation used for calculating the second operation amount is held without being reset. The inspection apparatus according to any one of claims 9 to 11.

Images