Temperature-adjusting method for substrate support table and inspection apparatus

Abstract

Provided is a method for adjusting the temperature of a substrate support table for supporting a substrate when inspecting a plurality of devices formed on the substrate. 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 provided in a shared manner among the plurality of devices. The method involves, at the time of switching an inspection target device: (A) a step for calculating a first operation amount by using a feedback control computation and on the basis of a target temperature and a temperature measured by a precedent temperature sensor which is one of the temperature sensors corresponding to a device having been inspected; (B) a step for calculating a second operation amount by using the feedback control computation and on the basis of the target temperature and a temperature measured by a subsequent temperature sensor which is one of the temperature sensors corresponding to a device to be inspected subsequently; (C) a step for adding together a value obtained by multiplying the first operation amount by a variable α that is equal to or less than 1 and a value obtained by multiplying the second operation amount by 1-α, to thereby calculate the operation amount of the temperature adjustment mechanism at the time of switching the inspection target; and (D) a step for outputting the operation amount of the temperature adjustment mechanism at the time of switching the inspection target. The variable α decreases over time and the decrease rate decreases over time.

Description

Temperature control method and inspection device for substrate support stand

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

[0002] Patent Document 1 describes a mounting table on which a device to be processed is placed, the mounting table including a top plate having a wafer mounting surface for 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 desired measurement positions in a plan view.

[0003] JP 2022-71468 A

[0004] The technology disclosed herein uses a common temperature adjustment mechanism among multiple devices formed on a substrate to adjust the temperature measured by a temperature sensor through feedback control, and when some devices are inspected, when the device to be inspected is switched, the temperature measured by the temperature sensor corresponding to the next device to be inspected is quickly stabilized.

[0005] One aspect of the present disclosure is 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, the substrate support table having a wafer mounting surface on which the substrate is mounted and a plurality of temperature sensors provided along the wafer mounting surface, a temperature adjustment mechanism that adjusts the temperature of the wafer mounting surface is provided in common among the plurality of devices, and the method includes, when switching a device to be inspected, (A) adjusting the temperature of the wafer mounting surface by a feedback control calculation based on a temperature measured by a previous temperature sensor that is the temperature sensor corresponding to the device that was the inspected device, and a target temperature. (B) calculating a first manipulated variable by a feedback control calculation based on the temperature measured by the next temperature sensor, which is the temperature sensor corresponding to the device to be next inspected, and a target temperature; (C) calculating an manipulated variable of the temperature adjustment mechanism when the inspection target is switched by adding a value obtained by multiplying the first manipulated variable by a variable α that is equal to or smaller than 1 and a value obtained by multiplying the second manipulated variable by 1-α; and (D) outputting the manipulated variable of the temperature adjustment mechanism when the inspection target is switched, wherein the variable α decreases over time, and the rate of decrease also decreases over time.

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

[0007] FIG. 1 is a perspective view showing an outline of the configuration of an inspection device according to this embodiment; FIG. 2 is a front view showing an outline of the configuration of an inspection device according to this embodiment; FIG. 3 is a cross-sectional view showing an outline of the configuration of a stage; FIG. 4 is a top view of the stage; FIG. 5 is a block diagram showing an example of a configuration relating to control of a temperature adjustment mechanism by a control unit; FIG. 6 is a block diagram showing another example 1 of a configuration relating to control of a temperature adjustment mechanism by a control unit; and FIG. 7 is a block diagram showing another example 2 of a configuration relating to control of a temperature adjustment mechanism by a control unit.

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

[0009] An inspection device, such as a prober, is provided with a substrate support table having a wafer mounting surface on which a substrate on which devices are formed is placed, and a probe card having a large number of probes is also attached. During inspection, the inspection device supplies electrical signals from a tester to the device via the probes while the device is in contact with the probes. Then, based on the electrical signals received by the tester from the device via the probes, it is determined whether the device is defective or not.

[0010] In this type of inspection device, when inspecting the electrical characteristics of a device, a temperature adjustment mechanism such as a heating mechanism or a cooling mechanism and a temperature sensor are provided for the purpose of simulating the device's mounting environment, and the temperature of the device formed on the substrate may be adjusted, i.e., controlled, by the temperature adjustment mechanism based on the measurement results from the temperature sensor.

[0011] Specifically, the temperature adjustment mechanism adjusts the temperature of the wafer mounting surface of the substrate. The wafer mounting surface may be divided into multiple regions, and a temperature adjustment mechanism may be provided to adjust the temperature of each region individually. That is, multiple temperature adjustment mechanisms may be provided. Multiple temperature sensors may also be provided along the wafer mounting surface of the substrate. When multiple temperature adjustment mechanisms and multiple temperature sensors are provided, during inspection, each temperature adjustment mechanism operates based on the measurement results of each temperature sensor, adjusting the temperature of the wafer mounting surface to a target temperature and uniformity across the surface.

[0012] The greater the number of temperature sensors and temperature adjustment mechanisms, the greater the temperature adjustment accuracy, and the greater the accuracy of device inspection. However, increasing the number of temperature adjustment mechanisms significantly increases costs. Furthermore, thermal influences between adjacent regions within the wafer mounting surface increase the difficulty of temperature control of the controlled object, resulting in high temperature controller costs. On the other hand, multiple temperature sensors can be implemented with only a slight increase in cost by using chip sensors, for example.

[0013] Therefore, a configuration may be adopted in which multiple temperature sensors are provided on the substrate support table and temperature is controlled by a single temperature control mechanism, i.e., a substrate support table may be provided with multiple temperature sensors and a single temperature control area is set on the wafer mounting surface of the substrate.

[0014] In recent years, in the inspection of logic integrated circuits as devices, the devices have become more highly integrated and faster, generating more heat, making it impossible to inspect all the devices formed on a substrate at once, and so inspections have become mainstream, either one device at a time or in batches of several devices.

[0015] When performing such an inspection, if multiple temperature sensors are provided on the substrate support table and the temperature is adjusted by a single temperature adjustment mechanism, the manipulated variable of the temperature adjustment mechanism is calculated by a feedback control calculation such as a PID control calculation based on the temperature measured by the temperature sensor corresponding to the device under inspection and the target temperature. Then, based on the calculation result, the temperature adjustment mechanism operates to adjust the temperature measured by the temperature sensor to the target temperature. The temperature adjustment by the temperature adjustment mechanism affects not only the device under inspection that generates heat, but also non-tested devices that do not generate heat. Therefore, during inspection, the temperature of the non-tested devices is lower than the target temperature.

[0016] Therefore, if the manipulated variable of the temperature control mechanism is suddenly switched from one based on the temperature measurement results of the temperature sensor corresponding to the previous device to one based on the temperature measurement results of the temperature sensor corresponding to the next device between the time when power is turned off for the previous device and the time when power is turned on for the next device, the following phenomenon occurs: The temperature measured by the temperature sensor corresponding to the next device (hereinafter referred to as the "next temperature sensor") does not settle in a short time, resulting in overshoot or undershoot. In particular, if the device generates a large amount of heat, it takes a long time for the temperature measured by the next temperature sensor to settle. If the temperature measured by the next temperature sensor does not settle, the next device will not be tested, resulting in a decrease in throughput. Weakening the gain of the feedback control calculation can suppress overshoot and undershoot, but weakening it will require a long time for the temperature measured by the next temperature sensor to reach the target temperature, ultimately resulting in a decrease in throughput. These issues are particularly noticeable in devices that generate a large amount of heat.

[0017] Therefore, the technology disclosed herein allows the temperature measured by the next temperature sensor to be quickly stabilized when switching between devices to be inspected in a case where multiple temperature sensors are provided on a substrate support table and the temperature is adjusted by a single temperature adjustment mechanism.

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

[0019] 1 and 2 are a perspective view and a front view, respectively, showing the outline of the configuration of the inspection device 1 according to this embodiment. In Fig. 2, a part of the inspection device 1 shown in Fig. 1 is shown in cross section to show components built into a storage chamber and a loader, which will be described later.

[0020] The inspection apparatus 1 inspects the electrical characteristics of devices (not shown) formed on a wafer W serving as a substrate. The wafer W has n (n is a natural number equal to or greater than 2) or a plurality of devices formed thereon, and the inspection apparatus 1 simultaneously inspects m (m is a natural number less than n) devices in one inspection. In the following description, the number of devices inspected in one inspection is assumed to be one. As shown in FIGS. 1 and 2 , the inspection apparatus 1 includes an accommodation chamber 2 that accommodates 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 accommodation chamber from above.

[0021] 2, the accommodation chamber 2 is a hollow housing having a stage 10 as a substrate support table for supporting the wafer W. The stage 10 holds the wafer W by suction so that the wafer W does not shift in position relative to the stage 10. The stage 10 is also configured to be movable in the horizontal and vertical directions, and this configuration allows the relative positions of a probe card 11 (described later) and the wafer W to be adjusted so that electrodes on the surface of the wafer W can come into contact with probes 11a of the probe card 11.

[0022] A probe card 11 is disposed above the stage 10 in the accommodation chamber 2 so as to face the stage 10. The probe card 11 has probes 11a that electrically contact electrodes of devices formed on the wafer W. The probe card 11 is also connected to the tester 4 via an interface 12. During an electrical characteristic test, each probe 11a contacts an electrode of each device formed on the wafer W, supplies power from the tester 4 to the device via the interface 12, and transmits a 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 transfer container, and transfers it to the stage 10 of the accommodation chamber 2. The loader 3 also 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] The loader 3 further includes a control unit 13. The control unit 13 processes computer-executable instructions that cause the inspection apparatus 1 to perform the various steps described in this disclosure. The control unit 13 may be configured to control each element of the inspection apparatus 1 to perform the various steps 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 may be realized, for example, by a computer. The processing unit may be configured to read from the storage unit a program that provides logic or routines that enable various control operations to be performed, and to execute the read program to perform various control operations. This program may be stored in the storage unit in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit and read from the storage unit by the processing unit for execution. The medium may be various computer-readable storage media or a communication line connected to the communication interface. The storage medium 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), a HDD (Hard Disk Drive), a SSD (Solid State Drive), or a combination thereof. The communication interface may communicate with the inspection device 1 via a communication line such as a LAN (Local Area Network). The control unit 13 may be provided in the storage chamber 2.

[0025] The tester 4 has a test board (not shown) that reproduces part of the circuit configuration of a motherboard on which a device is mounted. The test board is connected to a tester computer 15 that judges the acceptability of a device based on a signal from the device formed on the wafer W. The tester 4 can reproduce the circuit configurations of a variety of motherboards by changing the test board.

[0026] Furthermore, the inspection device 1 includes a user interface unit 16 for displaying information to a user and for the user to input instructions. 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 a device formed on a wafer W, the tester computer 15 transmits data to a test board connected to the device via each probe 11 a. The tester computer 15 then determines whether the transmitted data has been correctly processed by the test board based on an electrical signal from the test board.

[0028] <Stage 10> Next, the configuration of the stage 10 will be described with reference to Figures 3 and 4. Figure 3 is a cross-sectional view showing a schematic configuration of the stage 10. Figure 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 horizontal and vertical directions, via a thermal insulating part 20. The thermal insulating part 20 is made of, for example, resin, graphite, or ceramic with low thermal conductivity.

[0030] The stage 10 has, in order from the top, 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 mounting surface, serving as a substrate wafer mounting surface on which a wafer W is placed. Note that, 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 mounting surface 110a. The top plate 110 is formed, for example, in a circular plate shape. The top plate 110 is made of a material with high thermal conductivity and Young's modulus, and is thin to reduce its heat capacity. By reducing the heat capacity of the top plate 110, the temperature of the top plate 110 can be changed quickly, for example, by heating it with a heating plate 121 (described later). Note that the top plate 110 is made of a ceramic such as SiC or AlN, or, if further reduction in manufacturing costs is required, a metal such as copper or aluminum is used.

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

[0033] 3 constitutes at least a part of a temperature adjustment mechanism TM that adjusts the temperature of the wafer mounting surface 110a. The temperature adjustment plate 120 has 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, i.e., a member that heats the wafer mounting surface 110a. The heating plate 121 is formed, for example, in the shape of a disk. 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 mounting 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 when powered, and is made of, for example, tungsten.

[0035] Furthermore, the heating element is not embedded in the center of the heating plate 121, but is embedded only in the outer periphery of the heating plate 121, for example.

[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 circular plate 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 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. The refrigerant may be, for example, a fluorine-based liquid, a liquid such as ethylene glycol, or a gas such as nitrogen.

[0037] The port 123 is connected to a chiller unit (not shown). A coolant whose temperature has been adjusted by the chiller unit is supplied to the flow path 122a via the port 123. The chiller unit, the cooling plate 122, etc. constitute a cooling mechanism CM that cools the wafer mounting surface 110a.

[0038] <Control unit 13> Fig. 5 is a block diagram showing an example of the configuration of the control unit 13 for controlling the temperature adjustment mechanism TM. As shown in Fig. 5, the control unit 13 has a temperature acquisition unit 201, an operation amount calculation unit 202, and a temperature adjustment control unit 203. Of 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 approximately 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 whose temperature is to be acquired. The temperature sensor 111 corresponding to the device whose temperature is to be acquired is, for example, the temperature sensor closest to the device whose temperature is to be acquired.

[0040] For example, during an electrical characteristic test, the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 corresponding to the device under test, the temperature of which is to be acquired.

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

[0042] The manipulated variable calculation unit 202 calculates the manipulated variable of the temperature adjustment mechanism TM by feedback control calculation based on the temperature measured by the temperature sensor 111. Specifically, the manipulated variable calculation unit 202 calculates the manipulated variable of the heating plate 121 and the manipulated variable of the cooling mechanism CM by PID control calculation based on the temperature measured by the temperature sensor 111. The manipulated variable of the heating plate 121 is, for example, the power supplied to the resistance heating element. Furthermore, the manipulated variable of the cooling mechanism CM relates to at least one of the flow rate and temperature of the refrigerant, for example, and is specifically, for example, the opening degree of a flow rate adjustment valve.

[0043] The gain in the feedback control calculation (specifically, PID gain) is different between the gain used to calculate the operation amount of the heating plate 121 and the gain used to calculate the operation amount of the cooling mechanism CM. The gain in the feedback control calculation (specifically, PID gain) may be common to the temperature sensors 111, or may be different between the temperature sensors 111.

[0044] For example, during the inspection of electrical characteristics, the manipulated variable calculation unit 202 calculates the manipulated variable PVt of the temperature adjustment mechanism TM during 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 the calculated manipulated variable PVt to the temperature adjustment control unit 203. Specifically, during the inspection of electrical characteristics, the manipulated variable calculation unit 202 calculates the manipulated variable PVh of the heating plate 121 during 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 the calculated manipulated variable PVh to the temperature adjustment control unit 203. Similarly, the manipulated variable calculation unit 202 calculates the manipulated variable PVc of the cooling mechanism CM during inspection.

[0045] The operation amount calculator 202 includes a first operation amount calculator 211 , a second operation amount calculator 212 , and an output operation amount calculator 213 .

[0046] When switching between devices to be inspected, the first manipulated variable calculation unit 211 calculates a first manipulated variable PV1 for 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. Specifically, when switching between devices to be inspected, the first manipulated variable calculation unit 211 calculates a first manipulated variable PVh1 for the heating plate 121 by PID control calculation based on the temperature measured by the previous temperature sensor 111p and the target temperature. Similarly, when switching between devices to be inspected, the first manipulated variable calculation unit 211 calculates a first manipulated variable PVc1 for the cooling mechanism CM.

[0047] When switching between devices to be inspected, the second manipulated variable calculation unit 212 calculates a second manipulated variable PV2 for the temperature adjustment mechanism TM by 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 between devices to be inspected, the second manipulated variable calculation unit 212 calculates a second manipulated variable PVh2 for the heating plate 121 by PID control calculation based on the temperature measured by the next temperature sensor 111n and the target temperature. Similarly, when switching between devices to be inspected, the second manipulated variable calculation unit 212 calculates a second manipulated variable PVc2 for the cooling mechanism CM.

[0048] When switching the device to be inspected, the output manipulated variable calculation unit 213 adds the value obtained by multiplying the first manipulated variable PV1 of the temperature adjustment mechanism TM by a variable α, which is equal to or less than 1, and the value obtained by multiplying the second manipulated variable PV2 of the temperature adjustment mechanism TM by 1-α to calculate the manipulated variable PVs of the temperature adjustment mechanism TM when switching the device to be inspected. That is, the output manipulated variable calculation unit 213 calculates the manipulated variable PVs of the temperature adjustment mechanism TM when switching the device to be inspected 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 decreases over time. Specifically, the variable α decreases exponentially. More specifically, the variable α is expressed 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 predetermined based on the time allowed when switching between devices to be tested, and more specifically, based on, for example, an allowable index time. Also, in formula (X), t is the elapsed time since the previous test ended, specifically, the elapsed time since the test current for the previous device to be tested ended when switching between devices to be tested.

[0051] The variable α may be common to the temperature sensors 111 or may differ between the temperature sensors 111 .

[0052] Specifically, when switching the device to be inspected, the output manipulated variable calculation unit 213 calculates the manipulated variable PVhs of the heating plate 121 when switching the device to be inspected by adding the value obtained by multiplying the first manipulated variable PVh1 of the heating plate 121 by a variable α that is equal to or less than 1 and the value obtained by multiplying the second manipulated variable PVh2 of the heating plate 121 by 1-α. Similarly, when switching the device to be inspected, the output manipulated variable calculation unit 213 calculates the manipulated variable PVcs of the cooling mechanism CM when switching the device to be inspected.

[0053] Furthermore, the output manipulated variable calculation unit 213 outputs the manipulated variable PVs of the temperature adjustment mechanism TM when the inspection target is switched, specifically, the manipulated variable PVhs of the heating plate 121 when the inspection target is switched and the manipulated variable PVcs of the cooling mechanism CM when the inspection target is switched, to the temperature adjustment control unit 203. That is, in this embodiment, the output manipulated variable calculation unit 213 also serves as an output unit that outputs the manipulated variable PVs of the temperature adjustment mechanism TM when the device to be inspected is switched.

[0054] The temperature adjustment control unit 203 controls the temperature adjustment mechanism TM based on the input operation amount PVs of the temperature adjustment mechanism TM when the inspection target is switched. Specifically, the temperature adjustment control unit 203 controls the heating plate 121 based on the input operation amount PVhs of the heating plate 121 when the inspection target is switched. The temperature adjustment control unit 203 also controls the cooling mechanism CM based on the input operation amount PVcs of the cooling mechanism CM when the inspection target is switched.

[0055] <Inspection Flow> Next, an example of an inspection flow by the inspection apparatus 1 will be described. First, a wafer W is removed from a FOUP in the loader 3 and transported to and placed on the stage 10. Next, the stage 10 is moved, and a probe 11a provided above the stage 10 comes into contact with an electrode of a device to be inspected among multiple devices formed on the wafer W. Then, input of an inspection signal to the probe 11a begins. That is, power is started to be supplied to the device to be inspected. This starts inspection of the electrical characteristics of the device to be inspected. When the inspection of the electrical characteristics is completed, power is stopped from being supplied to the device to be inspected, and the probe 11a is separated from the electrode of that device. Then, the same process is performed for the next device to be inspected on the wafer W. Thereafter, the above-described processes are repeated until inspection of the electrical characteristics of all devices is completed.

[0056] <Temperature Control During Inspection> During the above-described electrical characteristic inspection, the temperature of the device under inspection must be maintained at a desired temperature. Therefore, for example, during the electrical characteristic inspection, the temperature acquisition unit 201 acquires the temperature of the portion of the wafer mounting surface 110a where the device under inspection is located, which is approximately equal to the temperature of the device under inspection. Specifically, the temperature acquisition unit 201 acquires the temperature measured by the temperature sensor 111 corresponding to the device under inspection. Furthermore, the manipulated variable calculation unit 202 calculates the deviation δ between the temperature acquired by the temperature acquisition unit 201 and the desired temperature, i.e., the target temperature, and, based on the deviation δ, calculates the manipulated variables PVh and PVc of the heating plate 121 and the cooling mechanism CM under inspection using PID control calculation, and outputs the calculated manipulated variables to the temperature adjustment control unit 203. The temperature adjustment control unit 203 then controls the heating plate 121 and the cooling mechanism CM based on the manipulated variables PVh and PVc of the heating plate 121 and the cooling mechanism CM under inspection. This ensures that the temperature of the device under inspection is constant at the target temperature.

[0057] <Temperature Control When Switching Test Target> When switching between devices to be tested, temperature control different from that during testing is performed.

[0058] Specifically, when switching the device to be inspected, first, power 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, i.e., 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, i.e., the next temperature sensor 111n.

[0059] Furthermore, the first manipulated variable calculation unit 211 calculates a deviation δp between the temperature measured by the previous temperature sensor 111p and the target temperature, and the second manipulated variable calculation unit 212 calculates a deviation δn between the temperature measured by the next temperature sensor 111n and the target temperature. Furthermore, the first manipulated variable calculation unit 211 calculates first manipulated variables PVh1, 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 manipulated variable calculation unit 212 calculates second manipulated variables PVh2, 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 variable calculation unit 213 adds together the value obtained by multiplying the first operation variable PVh1 of the heating plate 121 by the variable α and the value obtained by multiplying the second operation variable PVh2 of the heating plate 121 by 1-α to calculate the operation variable PVhs of the heating plate 121 when the inspection target is switched, and outputs this to the temperature adjustment control unit 203. Furthermore, the output operation variable calculation unit 213 adds together the value obtained by multiplying the first operation variable PVc1 of the cooling mechanism CM by the variable α and the value obtained by multiplying the second operation variable PVc2 of the cooling mechanism CM by 1-α to calculate the operation variable PVcs of the cooling mechanism CM when the inspection target is switched, and outputs this to the temperature adjustment control unit 203.

[0061] Then, the temperature adjustment 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 when the inspection target is switched.

[0062] When a first predetermined time has elapsed since power to the device being inspected was stopped, the temperature adjustment control unit 203 stops controlling the heating plate 121 and the cooling mechanism CM based on the manipulated variables PVhs and PVcs of the heating plate 121 and the cooling mechanism CM at the time of switching the inspection target. Instead, the temperature adjustment control unit 203 starts controlling the heating plate 121 and the cooling mechanism CM based on the second manipulated variables PVh2 and PVc2 of the heating plate 121 and the cooling mechanism CM. When the manipulated variables used to control the heating plate 121 and the cooling mechanism CM are changed, the integral value related to the integral control calculation used to calculate the second manipulated variables PVh2 and PVc2 may be held without being reset. In other words, when the manipulated variables are changed, the integral value held by the integrator (not shown) used to calculate the second manipulated variables PVh2 and PVc2 may not be reset.

[0063] Furthermore, when a first predetermined time has elapsed since power supply to the device to be inspected was stopped and the temperature measured by the next temperature sensor 111n continues to be within a range close to the target temperature (e.g., the target temperature ±1°) for a second predetermined time, power supply to the next device to be inspected can be started, i.e., electrical characteristic inspection of the next device to be inspected can be started.

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

[0065] <Major Effects> As described above, in this embodiment, the temperature adjustment mechanism TM that adjusts the temperature of the wafer mounting surface 110a of the stage 10 is provided in common among multiple devices, and multiple temperature sensors 111 are provided along the wafer mounting surface 110a. Furthermore, in this embodiment, when switching the device to be inspected, the first manipulated variable calculation unit 211 calculates a first manipulated variable 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 manipulated variable calculation unit 212 calculates a second manipulated variable 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 manipulated variable calculation unit 213 adds the value obtained by multiplying the first manipulated variable PV1 of the temperature adjustment mechanism TM by α (α is a variable equal to or less than 1 that decreases over time and the rate of decrease also decreases over time) to the value obtained by multiplying the second manipulated variable PV2 of the temperature adjustment mechanism TM by 1-α to calculate the manipulated variable PVs of the temperature adjustment mechanism TM when switching the test target. The calculated manipulated variable PVs is output to the temperature adjustment control unit 203 and used to control the temperature adjustment mechanism TM.

[0066] The device that was the test target corresponding to the previous temperature sensor 111n generated heat during the previous test, but its temperature was adjusted accordingly. Therefore, the deviation δp between the temperature measured by the previous temperature sensor 111p and the target temperature is small, approximately zero. Therefore, the first manipulated variable PV1 of the temperature adjustment mechanism TM is also small. On the other hand, the next test target device corresponding to the next temperature sensor 111n was not the test target during the previous test, so it was not powered and did not generate heat. However, it is adjusted to the same temperature as the test target device that generates heat during power application. Therefore, the deviation δn between the temperature measured by the next temperature sensor 111n and the target temperature is relatively large. Therefore, the second manipulated variable PV2 of the temperature adjustment mechanism TM is also large. In particular, immediately after switching the test target (specifically, immediately after starting temperature control during switching), the deviation δn is large, and the second manipulated variable PV2 of the temperature adjustment mechanism TM is also large.

[0067] Therefore, unlike the present embodiment, if the second manipulated variable PV2 of the temperature adjustment mechanism TM is continuously used to control the temperature adjustment mechanism TM from the beginning of the switchover when switching the device to be inspected, the manipulated variable of the temperature adjustment mechanism TM will be large at the beginning of the switchover, and the change in the temperature measured by the next temperature sensor 111n will also be large. As a result, an overshoot or undershoot will occur in the temperature measured by the next temperature sensor 111n. In other words, the settling time of the temperature measured by the next temperature sensor 111n will be long.

[0068] In contrast, in this embodiment, when switching the device to be inspected, the manipulated variable PVs of the temperature adjustment mechanism TM at the time of switching the inspection target is used to control the temperature adjustment mechanism TM, rather than 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 equal to or approximately equal to the first manipulated variable PV1 of the temperature adjustment mechanism TM at the beginning of switching. Furthermore, as described above, the first manipulated variable PV1 of the temperature adjustment mechanism TM is small. That is, in this embodiment, the manipulated variable of the temperature adjustment mechanism TM is small at the beginning of switching the inspection target. Therefore, according to this embodiment, the change in the temperature measured by the next temperature sensor 111n is also small at the beginning of switching the inspection target. As a result, overshoot or undershoot is unlikely to occur in the temperature measured by the next temperature sensor 111n. Furthermore, 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 quickly, the manipulated variable PVs of the temperature adjustment mechanism TM at the time of switching the inspection target described above is small at the beginning of switching the inspection target. Therefore, in this embodiment, the gain in the feedback control calculation can be increased. Therefore, according to this embodiment, when switching between devices to be inspected, the temperature measured by the next temperature sensor 111n can be made to reach the target temperature quickly while suppressing overshoot and undershoot. Therefore, according to this embodiment, in a case where a temperature adjustment mechanism TM that adjusts the temperature of the wafer mounting surface 110a of the stage 10 is provided in common among multiple devices and multiple temperature sensors 111 are provided along the wafer mounting surface 110a, the temperature measured by the next temperature sensor 111p can be made to settle quickly.

[0069] As described above, the gain in the feedback control calculation may be common to all temperature sensors 111. In this embodiment, even if a strong gain common to all temperature sensors 111 is adopted as the gain in the feedback control calculation, it is possible to prevent overshoot or undershoot from occurring in the temperature measured by the next temperature sensor 111n, regardless of which of the multiple temperature sensors 111 is the next temperature sensor 111n. If the gain in the feedback control calculation is common to all temperature sensors 111, setting the gain is easy.

[0070] Furthermore, by setting an appropriate variable α (specifically, time constant T) based on the time allowed when switching the device to be inspected (specifically, for example, the allowable index time), the temperature measured by the next temperature sensor 111p can be stabilized within the above-mentioned allowable time.

[0071] Furthermore, as described above, when the manipulated variables used to control the heating plate 121 and the cooling mechanism CM are changed from the manipulated variables PVhs and PVcs at the time of switching the inspection target to the second manipulated variables PVh2 and PVc2, the integral value involved in the integral control calculation used to calculate the second manipulated variables PVh2 and PVc2 may be maintained without being reset. This makes it possible to prevent overshoot or undershoot from occurring in the temperature measured by the next temperature sensor 111n by resetting the integral value. In other words, this makes it possible to prevent the time until the temperature measured by the next temperature sensor 111p settles from being prolonged by resetting the integral value.

[0072] <Another Example 1 of the Control Unit> Fig. 6 is a block diagram showing another example 1 of the configuration of the control unit for controlling the temperature adjustment mechanism TM. In the manipulated variable calculation unit 202 of the control unit 13 in Fig. 5, the output manipulated variable calculation unit 213 also serves as the output unit. In contrast, the manipulated variable calculation unit 202A of the control unit 13A in Fig. 6 has an output unit 221 in addition to the output manipulated variable calculation unit 213A.

[0073] The output manipulated variable calculation unit 213A differs from the output manipulated variable calculation unit 213 of FIG. 5 only in that it outputs the calculated manipulated variable PVs of the temperature adjustment mechanism when the inspection target is switched to the output unit 221. The output unit 221 performs base clipping on the manipulated variable PVs of the temperature adjustment mechanism TM when the inspection target is switched so that it does not fall within a dead band, and outputs the base clipped manipulated variable PVs' to the temperature adjustment control unit 203. Specifically, the output unit 221 performs base clipping on the manipulated variable PVs of the temperature adjustment mechanism TM when the inspection target is switched so that the manipulated variable PVs' output by the output unit 221 does not fall within a predetermined dead band. The base clipping is a process in which, when the manipulated variable is within the dead band, the manipulated variable is set to the upper limit of the dead band.

[0074] This makes it possible to appropriately adjust the temperature of the temperature adjustment target even when the manipulated variable output from the output unit 221 and input to the temperature adjustment control unit 203 has a dead zone that does not involve a change in the temperature of the temperature adjustment target. Specifically, this is as follows. That is, for example, when the manipulated variable of the cooling mechanism CM as the manipulated variable of the temperature adjustment mechanism relates to the opening of a flow control valve provided in the cooling mechanism CM, there may be a dead zone in which the opening does not change even when the manipulated variable changes. In this case, by performing the base clip processing as described above, it is possible to prevent the opening from increasing suddenly and causing a sudden change in the temperature measured by the next temperature sensor 111n.

[0075] Furthermore, the manipulated variable PVs' that has been base clipped by the output unit 221 may have hysteresis. That is, the output unit 221 may perform base clipping on the manipulated variable PVs of the temperature adjustment mechanism TM when switching the inspection target so that the manipulated variable output from the output unit 221 has hysteresis. Furthermore, the output unit 221 may perform further calculations on the manipulated variable after base clipping so that the manipulated variable output from the output unit 221 has hysteresis.

[0076] This makes it possible to compensate for differences in temperature change occurring in the temperature adjustment target even when the manipulated variable output from the output unit 221 and input to the temperature adjustment control unit 203 increases and decreases, even when the manipulated variable is the same. 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 of a flow rate adjustment valve provided in the cooling mechanism CM, if the opening differs when the flow rate adjustment valve is opened and closed, even when the manipulated variable is the same, this can be compensated for. As a result, unnecessary hunting can be suppressed.

[0077] <Another Example 2 of the Control Unit> Fig. 7 is a block diagram showing another example 2 of the configuration of the control unit for controlling the temperature adjustment mechanism TM. An operation input calculation unit 202B of a control unit 13B in Fig. 7 has a dead time compensation unit 231 in addition to the components of the operation input calculation unit 202 of the control unit 13 in Fig. 5.

[0078] The dead time compensator 231 calculates a compensation amount corresponding to the dead time Tw included in the transmission system from the input of the operation amount 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 using the Smith method.

[0079] Specifically, the dead time compensation unit 231 calculates the difference (T11-T12) between a temperature T11 corresponding to the manipulated variable in the transmission model of the heating plate 121 that does not take dead time into account and a temperature T12 corresponding to the manipulated variable in the transmission model of the heating plate 121 that takes dead time into account, as the dead time compensation amount δh applied to the heating plate 121. Furthermore, the dead time compensation unit 231 calculates the difference (T21-T22) between a temperature T21 corresponding to the manipulated variable in the transmission model of the cooling mechanism CM that does not take dead time into account and a temperature T22 corresponding to the manipulated variable in the transmission model of the cooling mechanism CM that takes dead time into account, as the dead time compensation amount δc applied to the cooling mechanism CM.

[0080] For example, the dead time and transmission model of the heating plate 121 differ between the temperature sensors 111. Specifically, if the heating element in the heating plate 121 is embedded only in the outer periphery, the dead time and transmission model of the heating plate 121 differ between the temperature sensor 111 provided in the center of the wafer mounting surface 110a and the temperature sensor 111 provided in the outer periphery. Also, for example, the dead time and dead time compensation amount δc of the cooling mechanism CM are common to all the temperature sensors 111. Specifically, if the operation amount of the cooling mechanism CM is related to the temperature of the refrigerant, there is dead time of the cooling mechanism CM, and the dead time and the dead time compensation amount δc are common to all the temperature sensors 111.

[0081] In this example, the first operation amount calculation unit 211A and the second operation amount calculation unit 212A respectively calculate 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 dead time compensation unit 231.

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

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

[0084] Furthermore, the first manipulated variable calculation unit 211A calculates a first manipulated variable PVc1 of the cooling mechanism CM based on a dead time compensation variable δc of the cooling mechanism CM that corresponds to the dead time common to the temperature sensors 111. Specifically, the first manipulated variable calculation unit 211A calculates a corrected deviation δp' by adding the dead time compensation variable δc of the cooling mechanism CM that corresponds to the dead 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. Then, the first manipulated variable calculation unit 211A calculates the first manipulated variable PVc1 of the cooling mechanism CM by PID control calculation based on the corrected deviation δp'.

[0085] Furthermore, the second manipulated variable calculation unit 212A calculates a second manipulated variable PVc2 of the cooling mechanism CM based on a dead time compensation variable δc of the cooling mechanism CM that corresponds to the dead time common to the temperature sensors 111. Specifically, the second manipulated variable calculation unit 212A adds the dead time compensation variable δc of the cooling mechanism CM that corresponds to the dead time common to the temperature sensors 111 to the deviation δn between the temperature measured by the subsequent temperature sensor 111n and the target temperature to calculate a corrected deviation δn'. Then, the second manipulated variable calculation unit 212A calculates a second manipulated variable PVh2 of the cooling mechanism CM by PID control calculation based on the corrected deviation δn'.

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

[0087] Specifically, even if there is a dead time between inputting the operation amount of the heating plate 121 to the temperature adjustment control unit 203 and outputting the temperature measurement result by the temperature sensor 111, the temperature measured by the next temperature sensor 111n can be more reliably stabilized. Furthermore, even if the dead time differs between the temperature sensors 111, the temperature measured by the next temperature sensor 111n can be stabilized regardless of the position of the next temperature sensor 111n.

[0088] Furthermore, even if there is a dead time between inputting the operating amount of the cooling mechanism CM to the temperature control control unit 203 and outputting the temperature measurement result by the temperature sensor 111, the temperature measured by the next temperature sensor 111n can be more reliably stabilized.

[0089] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. For example, the components of the above-described embodiments may be arbitrarily combined. Such an arbitrary combination naturally provides the functions and effects of each of the components involved in the combination, and also provides other functions and effects that are apparent to those skilled in the art from the description of this specification.

[0090] Furthermore, the effects described herein are merely descriptive or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that are apparent to those skilled in the art from the description of this specification, in addition to or in place of the above-described 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 mounting surface on which the substrate is mounted and a plurality of temperature sensors provided along the wafer mounting surface, and a temperature adjustment mechanism that adjusts the temperature of the wafer mounting surface is provided commonly among the plurality of devices, and the method includes, when switching between devices to be inspected, (A) calculating a first manipulated variable by feedback control calculation based on a temperature measured by the previous temperature sensor that is the temperature sensor corresponding to the device that was the inspected device and a target temperature, (B) calculating a second manipulated variable by feedback control calculation based on a temperature measured by the next temperature sensor that is the temperature sensor corresponding to the next device to be inspected and the target temperature, (C) calculating a manipulated variable of the temperature adjustment mechanism when switching between devices to be inspected by adding a value obtained by multiplying the first manipulated variable by a variable α that is equal to or smaller than 1 and a value obtained by multiplying the second manipulated variable by 1-α, and (D) outputting the manipulated variable of the temperature adjustment mechanism when switching between devices to be inspected. (2) The temperature control method for a substrate support pedestal, in which the variable α decreases over time and the rate of decrease decreases over time. (3) The temperature control method for a substrate support pedestal, in which the variable α decreases exponentially. (4) The temperature control method for a substrate support pedestal, in which the variable α is expressed based on the following formula (X): α=e -ｔ／Ｔ...(X) T: predetermined time constant t: elapsed time since the end of the previous inspection (4) The temperature adjustment method for a substrate support pedestal according to any one of (1) to (3), wherein the step (D) performs base clip processing on the manipulated variable of the temperature adjustment mechanism when switching the inspection target so that it does not fall within a dead band, and outputs the base clipped manipulated variable. (5) The temperature adjustment method for a substrate support pedestal according to (4), wherein the base clipped manipulated variable has hysteresis. (6) (E) The temperature adjustment method for a substrate support pedestal according to any one of (1) to (5), further comprising the step of calculating, by the Smith method, a compensation amount corresponding to a dead time included in a transmission system from the input of the manipulated variable to the temperature adjustment mechanism to the output of the temperature measurement result by the temperature sensor, (7) The temperature adjustment method for a substrate support stand according to (6), wherein the step (E) 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 step (A) calculates the first manipulated variable based on the compensation amount corresponding to the dead time for the previous temperature sensor, and the step (B) calculates the second manipulated variable based on the compensation amount corresponding to the dead time for the next temperature sensor. (8) The temperature adjustment method for a substrate support stand according to any one of (1) to (7), wherein, when the manipulated variable used to control the temperature adjustment mechanism is switched from the manipulated variable of the temperature adjustment mechanism at the time of switching the inspection target to the second manipulated variable, an integral value related to an integral control calculation used to calculate the second manipulated variable is held without being reset.(9) An inspection apparatus for inspecting a plurality of devices formed on a substrate, comprising: a substrate support table having a wafer mounting surface on which the substrate is mounted and a plurality of temperature sensors provided along the wafer mounting surface; a temperature adjustment mechanism for adjusting the temperature of the wafer mounting surface is provided, shared among the plurality of devices; a first operation variable calculation unit for calculating a first operation variable by feedback control calculation when switching between devices to be inspected, based on a temperature measured by a previous temperature sensor that is the temperature sensor corresponding to the device that was the inspection target, and a target temperature; a second operation variable calculation unit for calculating a second operation variable by feedback control calculation when switching between devices to be inspected, based on a temperature measured by a next temperature sensor that is the temperature sensor corresponding to the next device to be inspected, and the target temperature; an output operation variable calculation unit for calculating an operation variable of the temperature adjustment mechanism when switching between the devices to be inspected, by adding a value obtained by multiplying the first operation variable by a variable α that is equal to or less than 1 and a value obtained by multiplying the second operation variable by 1-α; and an output unit for outputting the operation variable of the temperature adjustment mechanism when switching between the devices to be inspected. (10) An inspection device according to (9), wherein the variable α decreases over time, and the rate of decrease decreases over time. (11) The inspection device according to (9), wherein the variable α decreases exponentially. (12) The inspection device according to (9), wherein the variable α is expressed based on the following formula (X): α=e. -ｔ／Ｔ...(X) T: predetermined time constant t: elapsed time since the end of the previous inspection (12) The inspection device according to any one of (9) to (11), wherein the output unit performs base clipping on the manipulated variable of the temperature adjustment mechanism when switching the inspection target so that it does not fall within a dead band, and outputs the base clipped manipulated variable. (13) The inspection device according to (12), wherein the base clipped manipulated variable has hysteresis. (14) The inspection device according to any one of (9) to (13), further comprising a dead time compensator that calculates a compensation amount corresponding to dead time included in a transmission system from input of the manipulated variable to the temperature adjustment mechanism to output of the temperature measurement result by the temperature sensor using the Smith method, wherein the first manipulated variable calculator and the second manipulated variable calculator calculate the first manipulated variable and the second manipulated variable, respectively, based on the compensation amount. (15) The inspection device according to (14), wherein the dead time compensator 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 manipulated variable calculator calculates the first manipulated variable based on the compensation amount corresponding to the dead time for the previous temperature sensor, and the second manipulated variable calculator calculates the second manipulated variable based on the compensation amount corresponding to the dead time for the next temperature sensor. (16) The inspection device according to any one of (9) to (15), wherein, when the manipulated variable used to control the temperature adjustment mechanism is switched from the manipulated variable of the temperature adjustment mechanism at the time of switching the inspection target to the second manipulated variable, an integral value related to an integral control operation used to calculate the second manipulated variable is held without being reset.

[0092] REFERENCE SIGNS LIST 1 Inspection device 10 Stage 110a Upper surface (wafer mounting 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 table that supports a substrate when inspecting a plurality of devices formed on the substrate, the 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, and a temperature adjustment mechanism for adjusting the temperature of the wafer placement surface being commonly provided among the plurality of devices, the method including: 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 a 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 an 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, 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 claim 1, wherein the variable α decreases exponentially.

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

5. The method for adjusting the temperature of a substrate support table according to claim 4, wherein the operation amount subjected to 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 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 table according to any one of claims 1 to 3.

7. The step (E) calculates 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. The step (A) calculates the first operation amount based on the compensation amount corresponding to the waste time for the previous temperature sensor. The step (B) calculates the second operation amount based on the compensation amount corresponding to the waste time for the next temperature sensor. The method for adjusting the temperature of the 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 integration value related to the integral control operation used for calculating the second operation amount is held without being reset. The method for adjusting the temperature of the 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, and a temperature adjustment mechanism for adjusting the temperature of the wafer placement surface, which is commonly provided among the plurality of devices. When switching the inspection target device, 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; 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; 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; and an output unit that outputs the operation amount of the temperature adjustment mechanism at the time of switching the inspection target. The variable α decreases over time, and the rate of decrease decreases over time.

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

11. The inspection apparatus according to claim 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 output unit 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 enter the dead zone, and outputs the operation amount subjected to the base clip processing. The inspection apparatus according to any one of claims 9 to 11.

13. The operation amount subjected to the base clip processing 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 calculate the first operation amount and the second operation amount based on the compensation amount, respectively. 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.

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