JP2023051113A - Inspection apparatus, and dew point management method - Google Patents

Abstract

To provide a technique capable of effectively preventing dew condensation of a chuck device or an inspected body.SOLUTION: An inspection apparatus performs an inspection on an inspected body. The inspection apparatus comprises: a housing including an inspection space; a chuck device which holds the inspected body; a temperature control module which supplies a coolant to the chuck device and controls a temperature of the inspected body; a dew point meter which detects a dew point temperature in the inspection space; and a humidity absorption module capable of controlling the dew point temperature in the inspection space. The humidity absorption module includes: a heat exchanger which is provided in the inspection space, condenses or coagulates moisture in the inspection space by supplying the coolant at a lower temperature than a temperature of the chuck device based on the dew point temperature detected by the dew point meter and controls the dew point temperature in the inspection space; and a discharge part which discharges the condensed or coagulated moisture to the heat exchanger.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to inspection devices and dew point management methods.

Japanese Unexamined Patent Application Publication No. 2002-200001 discloses an inspection apparatus that performs an electrical inspection of a semiconductor device provided on a substrate (wafer) that is an object to be inspected. The inspection apparatus includes a cooling supply unit (temperature control module) that supplies coolant to a chuck device (chuck top) that holds a wafer, and inspects the operation of semiconductor devices in a low temperature environment (eg, -30°C).

This type of inspection apparatus maintains the dew point in the inspection space by supplying dry air to the inspection space in order to prevent dew condensation on the chuck device and the wafer during low-temperature inspection.

JP 2019-29627 A

The present disclosure provides a technique capable of reducing energy consumption used to prevent dew condensation on a chuck device and an object to be inspected.

According to one aspect of the present disclosure, an inspection apparatus for inspecting an object to be inspected includes a housing having an inspection space, a chuck device provided in the inspection space and holding the object to be inspected, A temperature control module that supplies a coolant to the chuck device to adjust the temperature of the object to be inspected, a dew point meter that is provided in the inspection space and detects the dew point temperature of the inspection space, and a dew point temperature of the inspection space. The moisture absorption module is provided in the inspection space, and is supplied with a coolant having a temperature lower than the temperature of the chuck device based on the dew point temperature detected by the dew point meter. An inspection device is provided, comprising: a heat exchanger for condensing or solidifying moisture in the inspection space to adjust the dew point temperature of the inspection space; and an exhaust unit for discharging the moisture condensed or solidified in the heat exchanger. be done.

According to one aspect, it is possible to reduce energy consumption used to prevent dew condensation on the chuck device and the object to be inspected.

1 is a schematic longitudinal sectional view showing an inspection device according to one embodiment; FIG. 3 is a block diagram showing functional blocks of a controller; FIG. FIG. 4 is an explanatory diagram showing operations of a temperature control module and a moisture absorption module in a low temperature inspection; It is a flow chart which shows the dew point management method concerning this embodiment. FIG. 5(a) is a schematic explanatory diagram showing a moisture absorption module according to a first modified example. FIG. 5(b) is a schematic explanatory diagram showing a moisture absorption module according to a second modification. FIG. 6(a) is a schematic explanatory diagram showing a temperature control module and a moisture absorption module according to a third modified example. FIG. 6(b) is a schematic explanatory diagram showing a temperature control module and a moisture absorption module according to a fourth modification. FIG. 11 is a schematic plan view showing an inspection device and a moisture absorption module according to a fifth modified example;

Hereinafter, embodiments for carrying out the present disclosure will be described with reference to the drawings. In each drawing, the same components are denoted by the same reference numerals, and redundant description may be omitted.

FIG. 1 is a schematic longitudinal sectional view showing an inspection device 1 according to one embodiment. As shown in FIG. 1, an inspection apparatus 1 according to one embodiment inspects electrical characteristics of a plurality of semiconductor devices formed on a wafer (substrate) W, which is an example of a device under test (DUT). It is a device that The substrate is not limited to the wafer W, and may be a carrier on which semiconductor devices are arranged, a glass substrate, a single chip, an electronic circuit board, or the like.

The inspection apparatus 1 includes a housing 10 , a loader 20 arranged adjacent to the housing 10 , and a tester 30 arranged above the housing 10 . The housing 10 is formed in a rectangular parallelepiped shape (box shape) and has an inspection space 11 for inspecting the wafer W therein. The inspection apparatus 1 accommodates a stage 40 on which the wafer W is placed in the inspection space 11 . In addition, the inspection apparatus 1 has the lower side of the tester 30 arranged in the inspection space 11 , and the tester 30 holds the probe card 32 via the interface 31 .

The loader 20 takes out the wafer W from a FOUP (not shown), which is a transfer container, and places it on the stage 40 that has moved inside the housing 10 . Also, the loader 20 takes out the wafer W after the inspection from the stage 40 and stores it in the FOUP.

The tester 30 has therein a test board (not shown) that reproduces the circuit configuration of the wafer W on which semiconductor devices are provided, and is connected to the controller 80 of the inspection apparatus 1 . The test board judges whether the semiconductor device is good or bad based on the signal from the semiconductor device, and performs appropriate control. The tester 30 is configured to be able to reproduce the circuit configurations of multiple types of wafers W, for example, by switching between multiple test boards.

A probe card 32 held by the tester 30 has a large number of needle-like probes 32a (contact terminals) arranged corresponding to the electrode pads and solder bumps of each semiconductor device on the wafer W. As shown in FIG. Each probe 32 a supplies power from the tester 30 to the semiconductor device via the interface 31 or transmits a signal from the semiconductor device to the tester 30 via the interface 31 while being in contact with the wafer W. FIG.

The stage 40 is configured to be movable in the inspection space 11 of the housing 10 and transports the wafer W or the probe card 32 in the inspection space 11 . For example, the stage 40 transports the wafer W from the loader 20 to a position facing the probe card 32 and raises the wafer W toward the probe card 32 to enable inspection of the wafer W. FIG. After the inspection, the stage 40 lowers the wafer W after inspection from the probe card 32 and further conveys the wafer W toward the loader 20 .

Specifically, the stage 40 includes a moving unit 41 (X-axis moving mechanism 42 , Y-axis moving mechanism 43 , Z-axis moving mechanism 44 ), chuck device 45 and stage control unit 49 . The housing 10 also includes a frame structure 12 that supports the moving portion 41 of the stage 40, the chuck device 45, and the stage control portion 49 in two stages, upper and lower. For example, the frame structure 12 includes an upper base 12a that supports the moving section 41, a lower base 12b that supports the stage control section 49, and a plurality of columns 12c that are provided at the four corners of the lower base 12b and support the upper base 12a. , has

The X-axis moving mechanism 42 of the moving part 41 includes a plurality of guide rails 42a fixed to the upper surface of the upper base 12a and extending along the X-axis direction, and an X-axis movable body 42b arranged between the guide rails 42a. and including. The X-axis movable body 42 b has an X-axis motion unit (motor, gear mechanism, etc.) (not shown) inside, and this X-axis motion unit is connected to the stage control unit 49 . The X-axis movable body 42b reciprocates in the X-axis direction based on power supply from a motor driver (not shown) of the stage control section 49. As shown in FIG.

Similarly, the Y-axis moving mechanism 43 includes a plurality of guide rails 43a fixed to the upper surface of the X-axis movable body 42b and extending along the Y-axis direction, and a Y-axis movable body arranged between the guide rails 43a. 43b and . The Y-axis movable body 43 b also has a Y-axis operating section (motor, gear mechanism, etc.) (not shown) inside, and this Y-axis operating section is connected to the stage control section 49 . The Y-axis movable body 43b reciprocates in the Y-axis direction based on power supplied from a motor driver (not shown) of the stage control section 49. As shown in FIG.

The Z-axis moving mechanism 44 has a fixed body 44a installed on the Y-axis movable body 43b, and a Z-axis movable body 44b that moves up and down along the Z-axis direction relative to the fixed body 44a. A chuck device 45 is held on the upper portion of the body 44b. The Z-axis movable body 44 b has therein a Z-axis operating section (motor, gear mechanism, etc.) (not shown), and this Z-axis operating section is connected to the stage control section 49 . The Z-axis movable body 44b is displaced in the Z-axis direction (vertical direction) based on the power supply from the motor driver (not shown) of the stage control unit 49, thereby raising and lowering the wafer W held by the chuck device 45. In addition to moving the chuck device 45 in the X-axis direction, the Y-axis direction, and the Z-axis direction, the moving unit 41 may be configured to rotate the wafer W around the axis (θ direction).

The chuck device 45 conveyed by the moving part 41 holds the wafer W on its upper surface by suitable holding means (vacuum chuck, mechanical chuck, electrostatic chuck, etc.). The chuck device 45 has a bottom plate 46 engaged with the Z-axis movement mechanism 44 , a support block 47 stacked on top of the bottom plate 46 , and a chuck top 48 stacked on top of the support block 47 . . The bottom plate 46 is formed in an appropriate planar shape (substantially polygonal shape) that can be engaged with the Z-axis movable body 44b.

The support block 47 supports the chuck top 48 at an appropriate height position. The inspection apparatus 1 also has a temperature control module 50 inside the support block 47 for adjusting the temperature of the wafer W held by the chuck device 45 . Specifically, inside the support block 47, a channel 51 is provided as a temperature control module 50 through which a coolant such as liquid nitrogen can flow. The flow path 51 is formed in an appropriate shape (for example, a lattice shape, a concentric shape, etc.) along the horizontal direction inside the support block 47, and adjusts the temperature of the entire chuck top 48 as the coolant flows.

The temperature control module 50 includes a chuck coolant path 52 (a chuck supply path 53 and a chuck discharge path 54) connected to the flow path 51 of the support block 47, and a chiller unit connected to the chuck coolant path 52. 55 and

The chuck coolant path 52 is configured by a pipe having a passage through which coolant can flow. A flow control valve 56 is provided in the middle of the supply path 53 for chuck. The flow rate adjustment valve 56 is connected to the controller 80 and adjusts the flow rate of the coolant supplied to the chuck device 45 by changing the degree of opening based on the control of the controller 80 .

The chiller unit 55 is installed at a position adjacent to the outside of the housing 10, and has a tank that stores the refrigerant, a refrigerant temperature adjustment unit that adjusts the temperature of the refrigerant to a target temperature, a pump that circulates the refrigerant, and the like (both not shown). During operation, the chiller unit 55 pushes the coolant to the chuck supply path 53 by means of a pump, thereby applying coolant supply pressure (positive pressure) from the chiller unit 55 to the chuck supply path 53 . The coolant supplied from the chiller unit 55 to the chuck supply path 53 in response to the opening of the flow control valve 56 flows through the chuck supply path 53 into the flow path 51 . The coolant cools the wafer W held on the chuck top 48 while flowing through the flow path 51 within the chuck device 45 . The coolant that has flowed through the flow path 51 flows out to the chuck discharge path 54 and returns to the chiller unit 55 via the chuck discharge path 54 . Note that the temperature control module 50 is not limited to the coolant channel 51 and may include a heater for heating the wafer W, for example.

The chuck top 48 is formed in a substantially disc shape having a diameter larger than that of the wafer W. As shown in FIG. The upper surface of the chuck top 48 serves as a mounting surface 48s on which the wafer W is mounted. A temperature sensor 48t is provided inside the chuck top 48 to detect the temperature of the wafer W (mounting surface 48s). The temperature sensor 48t is connected to the controller 80 of the inspection apparatus 1, and outputs the temperature detected during inspection to the controller 80. FIG.

For the chuck device 45 described above, an appropriate mechanism may be applied according to the means for holding the wafer W. FIG. For example, when the wafer W is vacuum-sucked, the holding means preferably has suction passages for suction in the support block 47 and the chuck top 48, and is provided with pipes and suction pumps connected to the suction passages at appropriate locations. . Alternatively, in the case of a mechanical chuck, the holding means preferably has one or more pressing members disposed on the outer periphery of the chuck top 48 and a mechanism for operating the pressing members. In the case of electrostatic attraction, the chuck top 48 may be a dielectric plate, and a DC power supply for supplying DC power to the electrodes in the dielectric plate may be provided at an appropriate location.

The stage control section 49 is connected to the controller 80 and controls the operation of the stage 40 based on commands from the controller 80 . The stage control unit 49 includes, for example, a main control unit that controls the operation of the entire stage 40, a PLC and motor drivers that control the operation of the moving unit 41, an illumination control unit, a power supply unit, and the like (both not shown).

The inspection apparatus 1 according to this embodiment also includes a pressure adjustment unit 60 that keeps the pressure (internal pressure) of the inspection space 11 inside the housing 10 at a positive pressure. The pressure adjustment unit 60 includes an air source (not shown) provided outside the housing 10, an air pipe 61 connected to the air source and extending into the housing 10, and an end of the air pipe 61. and one or more air nozzles 62 . Alternatively, the pressure adjustment unit 60 may include an exhaust unit (not shown) that exhausts the gas in the examination space 11 inside the housing 10 .

For example, the air source generates dry air with little (or no) moisture and delivers the dry air to the air line 61 . The air nozzle 62 is provided in the upper part of the housing 10 and discharges dry air supplied through the air pipe 61 into the inspection space 11 . The pressure adjustment unit 60 adjusts the test space 11 to a positive pressure (for example, atmospheric pressure or higher) in order to prevent gas containing moisture from flowing into the test space 11 from the outside of the housing 10. is. Therefore, the pressure adjustment unit 60 sends out a small amount of dry air from the air source and gently discharges the dry air from the air nozzle 62 into the inspection space 11 . As a result, the inspection space 11 becomes a stable airflow, and the inspection apparatus 1 can inspect the wafer W satisfactorily.

The inspection apparatus 1 according to this embodiment includes the dew point meter 13 and the moisture absorption module 70 in the inspection space 11 inside the housing 10 . The dew point meter 13 is arranged at an appropriate position within the inspection space 11 (for example, a position near the probe card 32 ) and detects the dew point temperature of the inspection space 11 . The dew point meter 13 is also connected to the controller 80 and outputs the detected value (information on the dew point temperature) to the controller 80 .

The moisture absorption module 70 includes a heat exchanger 71 provided in the housing 10, a heat exchanger refrigerant path 72 (a heat exchanger supply path 73 and a heat exchanger discharge path 74) connected to the heat exchanger 71, It includes a heating portion 75 that heats the heat exchanger 71 and a discharge portion 77 that discharges moisture. Also, the moisture absorption module 70 shares the temperature control module 50 and the chiller unit 55 as a supply source for supplying refrigerant to the heat exchanger 71 . That is, the chiller unit 55 is a coolant supply source for both the temperature control module 50 and the moisture absorption module 70 .

The heat exchanger coolant path 72 is also configured by a pipe having a passage through which coolant can flow, like the chuck coolant path 52 . Specifically, the heat exchanger supply path 73 is connected to a midway position of the chuck supply path 53 , and the heat exchanger discharge path 74 is connected to a midway position of the chuck discharge path 54 . The heat exchanger coolant path 72 may be directly connected to the chiller unit 55 without being connected to the chuck coolant path 52 .

The heat exchanger 71 is provided at a position adjacent to the moving part 41 on the upper base 12 a of the frame structure 12 and at a position lower than the chuck device 45 and exposed to the inspection space 11 . The heat exchanger 71 can apply a well-known structure (multi-tube type, tube plate, spiral tube, serpentine tube, etc.) that circulates a refrigerant inside tubes (not shown) and exchanges heat with the surrounding space. The dew point meter 13 and the heat exchanger 71 are preferably arranged above the upper base 12 a , but the arrangement position is not limited, and they may be in the same inspection space 11 as the chuck device 45 .

Here, the temperature of the chuck device 45 rises due to the wafer W receiving electrical energy from the tester 30 during inspection of the wafer W. FIG. In other words, even if refrigerant is supplied from the same chiller unit 55 to each of the chuck device 45 and the heat exchanger 71 , the temperature of the refrigerant in the heat exchanger 71 is lower than the temperature of the chuck device 45 . That is, the temperature of the heat exchanger 71 becomes lower than the temperature of the chuck device 45 , so that the surface of the heat exchanger 71 can freeze moisture in the gas in the inspection space 11 . The heat exchanger 71 reduces the amount of moisture (the amount of water vapor) in the inspection space 11 , so that the inspection apparatus 1 can prevent freezing of moisture in the chuck device 45 .

The moisture absorption module 70 also includes an open/close valve 76 in the middle of the heat exchanger supply path 73 that supplies refrigerant to the heat exchanger 71 . The open/close valve 76 is connected to a controller 80 and switched between open/close (fully open and fully closed) based on the control of the controller 80 . That is, the moisture absorption module 70 supplies refrigerant from the chiller unit 55 to the heat exchanger 71 when the on-off valve 76 is open, and stops the supply of refrigerant from the chiller unit 55 to the heat exchanger 71 when the on-off valve 76 is closed. do. Note that the moisture absorption module 70 may also include an adjustment valve capable of adjusting the flow rate of the refrigerant.

The heating unit 75 heats the heat exchanger 71 to melt the frost (frozen water) adhering to the heat exchanger 71 and change it into liquid water. The structure of the heating unit 75 is not particularly limited, and a structure in which a heating wire is arranged on the surface of the heat exchanger 71, a structure in which heat is radiated to the heat exchanger 71, or the like can be applied. The heating unit 75 is connected to the controller 80, and the operation is started and stopped based on the control of the controller 80, and the amount of heating is adjusted.

The discharge part 77 discharges the liquid water generated from the heat exchanger 71 by the heating of the heating part 75 to the outside of the housing 10 . For example, the discharge section 77 has a tray 77a for receiving liquid water that has fallen from the heat exchanger 71, a drain pipe 77b connected to the tray 77a, and a drain pump 77p provided at an appropriate position on the drain pipe 77b. . Under the control of the controller 80, the drain pump 77p applies negative pressure to the tray 77a (or the heat exchanger 71) through the passage in the drain pipe 77b, thereby sucking liquid water generated in the heat exchanger 71, This liquid water is discharged to a waste section (not shown) on the downstream side of the drain pipe 77b.

A well-known computer having one or more processors 81, memory 82, input/output interfaces and electronic circuits (not shown) can be applied to the controller 80 of the inspection apparatus 1. FIG. The one or more processors 81 are a combination of one or more of a CPU, an ASIC, an FPGA, circuits made up of multiple discrete semiconductors, and the like. The memory 82 includes a non-volatile memory and a volatile memory, and forms a storage section of the inspection device 1 .

When the controller 80 is activated, the processor 81 executes a program stored in the memory 82 to control each component of the inspection apparatus 1 and inspect the wafer W. FIG. In particular, the inspection apparatus 1 according to the present embodiment inspects the wafer W by lowering the temperature of the wafer W using the temperature control module 50 (hereinafter also referred to as a low temperature inspection) in order to check the operation of the wafer W in a low temperature environment. Therefore, the controller 80 constructs functional blocks as shown in FIG. 2 under the execution of the program by the processor 81 .

FIG. 2 is a block diagram showing functional blocks of the controller 80. As shown in FIG. 3A and 3B are explanatory diagrams showing the operation of the temperature control module 50 and the moisture absorption module 70 in the low temperature inspection. FIG. 3A shows the stopped state of the moisture absorption module 70, and FIG. , and (c) shows the state of draining liquid water from the heat exchanger 71 . For convenience of explanation, FIG. 3 omits a configuration (exhaust path) for returning the refrigerant from the chuck device 45 and the heat exchanger 71 to the chiller unit 55 .

As shown in FIG. 2, the controller 80 includes a chuck temperature control section 90, a pressure control section 91, a movement command section 92, an inspection command section 93, a dew point monitor section 94, a moisture absorption control section 95, and a discharge control section 96 in the low temperature inspection. to form

The chuck temperature control unit 90 is a functional unit that controls the temperature control module 50 to adjust the temperature of the wafer W (the mounting surface 48 s of the chuck top 48 ) held by the chuck device 45 . A target temperature for low-temperature inspection (low-temperature environment) is, for example, -30° C. or less. This target temperature can be arbitrarily set according to the specifications of the wafer W by operating the user interface of the controller 80 by the user of the inspection apparatus 1 .

The chuck temperature control unit 90 opens the flow rate adjustment valve 56 during low-temperature inspection to supply coolant from the chiller unit 55 to the chuck device 45 (support block 47) as shown in FIG. Adjust the temperature of W. At this time, the chuck temperature control unit 90 receives the detected temperature of the wafer W detected by the temperature sensor 48t, and controls the opening degree of the flow control valve 56 based on this detected temperature. As a result, the temperature control module 50 can adjust the flow rate of the coolant and adjust the temperature of the wafer W to the set target temperature. For example, the chuck temperature control unit 90 reduces the degree of opening of the flow rate adjustment valve 56 when the detected temperature is lower than the target temperature, and increases the degree of opening of the flow rate adjustment valve 56 when the detected temperature is higher than the target temperature. Enlarge.

The pressure adjustment unit 60 adjusts the pressure in the examination space 11 inside the housing 10 . The pressure adjustment unit 60 receives, for example, pressure detected by pressure sensors (not shown) provided outside and inside the housing 10, and adjusts the amount of dry air supplied from the air source to the air nozzle 62 based on the detected pressure. . In the low-temperature inspection, the pressure control unit 91 may adjust the supply amount of dry air to such an extent that the inspection space 11 is maintained at a positive pressure. This prevents gas containing moisture from flowing into the inspection space 11 from the outside of the housing 10 .

Further, the movement command unit 92 commands the stage control unit 49 to transfer the wafer W (transfer from the loader 20 to the tester 30, transfer from the tester 30 to the loader 20, etc.) at an appropriate timing. The inspection command unit 93 commands the tester 30 to inspect the wafer W after the stage control unit 49 transfers the wafer W to the tester 30 (probe card 32 ). Thereby, the tester 30 conducts an electrical inspection of the wafer W. FIG.

Then, the dew point monitoring unit 94, the moisture absorption control unit 95, and the discharge control unit 96 adjust the dew point of the inspection space 11 using the moisture absorption module 70 in order to suppress dew condensation on the chuck device 45 and the wafer W in the low temperature inspection. control. Specifically, the dew point monitoring unit 94 acquires information on the dew point temperature detected by the dew point meter 13 during the low temperature inspection, and continuously monitors the dew point temperature of the inspection space 11 .

For example, the dew point monitoring unit 94 compares the start threshold Ts for determining the start of cooling by the heat exchanger 71 with the dew point temperature, and when the dew point temperature exceeds the start threshold Ts, the heat exchanger 71 Moisture absorption is carried out. The start threshold Ts may be a value predefined according to a recipe or the like, or may be set based on the target temperature of the temperature control module 50 or the detected temperature (actually measured value) of the temperature sensor 48 t of the chuck device 45 . For example, the dew point monitoring unit 94 has a threshold setting unit 94a that sets the start threshold Ts, and the threshold setting unit 94a adds a predetermined negative temperature value to the target temperature of the temperature control module 50, Set the start threshold Ts. As a result, the timing at which the dew point temperature exceeds the start threshold value Ts is before condensation occurs on the chuck device 45 . That is, the inspection apparatus 1 can start moisture absorption by the heat exchanger 71 before dew condensation occurs on the chuck device 45 .

The moisture absorption control unit 95 controls the supply and stop of the refrigerant supply to the heat exchanger 71 by controlling the opening/closing valve 76 of the heat exchanger supply path 73 based on the instruction from the dew point monitoring unit 94 . As shown in FIG. 3B, opening the on-off valve 76 causes the refrigerant to circulate between the chiller unit 55 and the heat exchanger 71, so that the temperature of the heat exchanger 71 becomes higher than the temperature of the chuck device 45. lower. The heat exchanger 71 freezes the moisture in the inspection space 11 and adsorbs the moisture on its surface. As a result, the water content (the amount of water vapor) in the gas decreases, and the dew point temperature of the inspection space 11 decreases. As a result, the heat exchanger 71 can reduce the dew point temperature before condensation occurs on the chuck device 45 and prevent condensation on the chuck device 45 .

Further, the dew point monitoring unit 94 compares the dew point temperature with the stop threshold Te when the heat exchanger 71 operates, and stops the operation of the heat exchanger 71 when the dew point temperature becomes equal to or lower than the stop threshold Te. do. The stop threshold Te is preferably set to be equal to or less than the start threshold Ts. The stop threshold Te may also be a predetermined value, or a value set by the threshold setting unit 94a based on the target temperature of the temperature control module 50 or the detected temperature (actual value) of the temperature sensor 48t of the chuck device 45. Note that the dew point monitoring unit 94 is not limited to stopping the operation of the heat exchanger 71 based on the dew point temperature. Operation may be stopped if the duration exceeds a duration threshold.

Furthermore, when the heat exchanger 71 operates, the dew point monitoring unit 94 detects frost ( The state of frozen water) is estimated, and the operation of the heating unit 75 and the discharging unit 77 is determined. For this reason, the dew point monitoring unit 94 has a change threshold Tc that indicates the amount of decrease per unit time, and compares the changing tendency of the dew point temperature with the change threshold Tc during the operation of the heat exchanger 71 . When the change tendency (slope) of the dew point temperature is larger than the change threshold value Tc, it means that the heat exchanger 71 has sufficient moisture absorption capability. Therefore, the dew point monitor 94 continues the operation of the heat exchanger 71 . On the other hand, when the change tendency of the dew point temperature is smaller than the change threshold value Tc, it can be estimated that the heat exchanger 71 is covered with frost and the moisture absorption capacity has decreased. Therefore, the dew point monitoring unit 94 outputs an instruction to defrost the heat exchanger 71 to the moisture absorption control unit 95 and the discharge control unit 96 .

As a result, the moisture absorption control unit 95 closes the opening/closing valve 76 to stop the supply of the refrigerant to the heat exchanger 71, as shown in FIG. 3(c). In addition, the discharge control unit 96 heats the heating unit 75 to melt water in the heat exchanger 71 into liquid water for defrosting. Further, the discharge control section 96 sucks the liquid water generated in the heat exchanger 71 by the discharge pump 77p of the discharge section 77 at an appropriate timing. As a result, liquid water (moisture) is smoothly discharged from the heat exchanger 71 .

The inspection apparatus 1 according to this embodiment is basically configured as described above, and the operation thereof will be described below.

As shown in FIG. 2, the inspection apparatus 1 adjusts the temperature of the wafer W under the control of the chuck temperature control unit 90 and performs low temperature inspection in order to check the operation of the wafer W in a low temperature environment. In the low-temperature inspection, the chuck temperature control unit 90 circulates the supply amount of the coolant appropriately adjusted by the flow rate adjustment valve 56 between the chiller unit 55 and the chuck device 45, thereby adjusting the mounting surface 48s of the chuck top 48. to reach the target temperature for cryogenic testing. At this time, the chuck temperature control unit 90 acquires the temperature detection value detected by the temperature sensor 48t in the chuck device 45, and adjusts the opening degree of the flow control valve 56 based on the temperature detection value. As a result, the temperature of the mounting surface 48s of the chuck top 48 smoothly reaches the target temperature and is maintained near the target temperature.

The pressure control section 91 of the controller 80 controls the pressure adjustment section 60 to supply dry air to the inspection space 11 through the air nozzle 62 . The pressure inside the housing 10 is higher (positive pressure) than the outside of the housing 10 (atmospheric pressure), and it is possible to prevent air containing moisture from flowing into the inspection space 11 from the outside of the housing 10. .

Then, the movement command section 92 of the controller 80 outputs to the stage control section 49 a command to transport the wafer W to the tester 30 in the low temperature inspection. The stage control unit 49 controls the moving unit 41 of the stage 40 to move the chuck device 45 to the loader 20 and receive the wafer W from the loader 20 . After receiving the wafer W from the loader 20 to the stage 40, the stage control unit 49 moves the moving unit 41 in the horizontal direction (X-axis-Y-axis direction) so that the wafer W faces the probe card 32 of the predetermined tester 30. Align so that After the alignment, the stage controller 49 raises the chuck device 45 by the stage 40 to bring the wafer W into contact with the probes 32 a of the probe card 32 .

In this state, the test command unit 93 instructs the tester 30 to start the test, and the tester 30 performs an electrical test (low temperature test) of the wafer W. FIG. During the low-temperature inspection, the chuck temperature control unit 90 continues to control the temperature control module 50 to adjust the temperature of the wafer W placed on the chuck top 48 to the target temperature. Thereby, the controller 80 can obtain the inspection result of the wafer W in the low-temperature environment from the tester 30 . After the low-temperature inspection by the tester 30 is completed, the inspection command unit 93 outputs a command to take out the wafer W from the tester 30 to the stage control unit 49 . Based on this command, the stage control unit 49 performs the reverse operation to lower and horizontally move the wafer W after inspection, and returns the wafer W to the loader 20 .

Further, the inspection apparatus 1 implements a dew point control method for managing the dew point of the inspection apparatus 1 in order to prevent dew condensation on the tester 30, the probe card 32, the chuck device 45 and the wafer W during the low temperature inspection of the wafer W. This dew point control method will be described below with reference to FIG. FIG. 4 is a flow chart showing the dew point control method according to this embodiment.

At the start of the dew point control method, the controller 80 puts the heat exchanger 71 in a non-operating state by closing the on-off valve 76 . In the dew point management method, the dew point monitor 94 of the controller 80 continuously receives information on the dew point temperature detected by the dew point meter 13 and stores it in the memory 82 (step S1).

Then, the dew point monitoring unit 94 compares the acquired dew point temperature with a preset start threshold Ts, and determines whether the dew point temperature exceeds the start threshold Ts (step S2). When the dew point temperature is equal to or lower than the start threshold Ts, dew condensation does not occur on the chuck device 45 or the wafer W in the inspection space 11 even if the heat exchanger 71 does not operate (see also FIG. 3A). ). Therefore, when the dew point temperature is equal to or lower than the start threshold Ts (step S2: NO), the dew point monitor 94 returns to step S1 and repeats the same processing flow. On the other hand, when the dew point temperature exceeds the start threshold value Ts, it means that the chuck device 45 and the wafer W are approaching a state where dew condensation is likely to occur. Therefore, when the dew point temperature exceeds the start threshold value Ts (step S2: YES), the process proceeds to step S3, and the dew point monitoring unit 94 instructs the moisture absorption control unit 95 to start the moisture absorption process.

In step S3, the moisture absorption control unit 95 opens the open/close valve 76 of the heat exchanger supply path 73 that was closed before the moisture absorption process. As a result, the refrigerant circulates between the chiller unit 55 and the heat exchanger 71 via the heat exchanger refrigerant path 72, and the temperature of the heat exchanger 71 decreases as the refrigerant circulates (Fig. 3(b)). As described above, since the temperature of the coolant in the heat exchanger 71 is lower than the temperature of the chuck device 45 , the temperature of the heat exchanger 71 is the lowest in the inspection space 11 . Therefore, the moisture in the gas in the inspection space 11 freezes in the heat exchanger 71, thereby reducing the moisture content (the amount of water vapor) in the inspection space 11 as a whole. That is, the heat exchanger 71 reduces the dew point temperature of the inspection space 11 .

Further, the dew point monitoring unit 94 receives dew point temperature information from the dew point meter 13 and continuously monitors the dew point temperature even while the on-off valve 76 is open (step S4). At this time, the dew point monitoring unit 94 determines the change tendency of the dew point temperature (step S5). That is, when the dew point temperature has a large tendency to change per unit time, it can be said that the heat exchanger 71 continues to adsorb moisture, in other words, the moisture absorption capacity is high.

For this reason, the dew point monitoring unit 94 proceeds to step S6 when the change tendency of the dew point temperature is greater than the change threshold value Tc (step S5: YES). In step S<b>6 , the controller 80 determines whether or not to stop the moisture absorption process by the heat exchanger 71 . In determining whether to stop the moisture absorption process, for example, it is monitored whether or not the dew point temperature has reached a set stop threshold Te. If the moisture absorption process is to be continued (step S6: NO), the controller 80 returns to step S5 and repeats the same process. On the other hand, if the moisture absorption process is terminated (step S6: YES), the moisture absorption control section 95 proceeds to step S7 and closes the open/close valve 76 of the heat exchanger supply path 73. FIG. Thereby, the inspection apparatus 1 ends the moisture absorption process by the moisture absorption module 70 . When the moisture absorption process is finished, the amount of water vapor in the inspection space 11 is reduced and the dew point temperature is lowered. Therefore, the inspection apparatus 1 can satisfactorily perform the low-temperature inspection by the tester 30 in a state where dew condensation in the inspection space 11 is suppressed.

On the other hand, when the degree of decrease in the dew point temperature per unit time is small or does not decrease, it can be said that frost (moisture) adheres to the surface of the heat exchanger 71 and the hygroscopic ability is reduced. Therefore, the dew point monitoring unit 94 proceeds to step S8 when the change tendency of the dew point temperature is smaller than the change threshold value Tc (step S5: NO). In step S8, the moisture absorption control unit 95 closes the on-off valve 76 to stop the supply of the refrigerant to the heat exchanger 71, and the discharge control unit 96 operates the heating unit 75 to stop the heat exchanger 71. Heat (see also FIG. 3(c)).

As a result, the frost adhering to the heat exchanger 71 melts and becomes liquid water, and the liquid water is discharged to the outside of the inspection space 11 through the tray 77a and the drain pipe 77b. At this time, the discharge control unit 96 operates the discharge pump 77p of the discharge unit 77 at an appropriate timing to suck the liquid water, thereby smoothly discharging the liquid water. The discharge control unit 96 controls the heating of the heat exchanger 71 by the heating unit 75 so as to liquefy the ice without evaporating it, thereby suppressing an increase in the dew point temperature.

The discharge control unit 96 stops the heating unit 75 after heating the heating unit 75 for a predetermined period. Then, the moisture absorption control unit 95 opens the open/close valve 76 again to return to cooling (moisture absorption) by the heat exchanger 71 (step S9). Furthermore, the controller 80 may determine the end of the moisture absorption process by proceeding to step S6. The heating (defrosting) of the heat exchanger 71 by the heating unit 75 is not performed during the low temperature inspection of the wafer W, but is performed between the low temperature inspection of one wafer W and the low temperature inspection of the other wafer W. good too. As a result, the influence of the heating of the heating unit 75 can be suppressed during the low-temperature inspection of the wafer W. FIG.

The inspection device 1 and the dew point management method according to the present disclosure are not limited to the above embodiments, and can take various modifications. For example, it is preferable that the heating unit 75 and the discharging unit 77 operate at the end of startup of the inspection device 1 to defrost the heat exchanger 71 . As a result, the heat exchanger 71 can be stably used when the inspection apparatus 1 operates next time.

FIG. 5(a) is a schematic explanatory diagram showing a moisture absorption module 70A according to a first modified example. FIG. 5(b) is a schematic explanatory diagram showing a moisture absorption module 70B according to a second modification. FIG. 6(a) is a schematic explanatory diagram showing a temperature control module 50A and a moisture absorption module 70C according to a third modification. FIG. 6(b) is a schematic explanatory diagram showing a temperature control module 50B and a moisture absorption module 70D according to a fourth modification. FIG. 7 is a schematic plan view showing an inspection device 1A and a moisture absorption module 70 according to the fifth modification.

A moisture absorption module 70A according to the first modification shown in FIG. 5A includes a plurality of heat exchangers 71 (two in this modification) in the inspection space 11 . In this case, the heat exchanger refrigerant path 72 includes a first path 721 that circulates the refrigerant between the first heat exchanger 711 and the chiller unit 55 and a refrigerant path between the second heat exchanger 712 and the chiller unit 55 . and a second route 722 that circulates the An on-off valve 76 is provided for each of the first path 721 and the second path 722 .

When the controller 80 (see FIG. 1) has a plurality of heat exchangers 71, the controller 80 operates the plurality of heat exchangers 71 simultaneously or selects some of the heat exchangers 71 based on the dew point temperature of the dew point meter 13. can be operated effectively. Further, the controller 80 can sequentially operate the heating units 75 of the plurality of heat exchangers 71 when defrosting the heat exchangers 71 by the heating units 75 . For example, the controller 80 first heats the first heat exchanger 711, performs moisture absorption by the second heat exchanger 712 during this process, then heats the second heat exchanger 712, and heats the second heat exchanger 712. Moisture absorption is performed by the first heat exchanger 711 during the period. As a result, the inspection apparatus 1 can discharge absorbed moisture while lowering the dew point temperature of the inspection space 11 .

A moisture absorption module 70B according to a second modification shown in FIG. 5B includes a chiller unit 55A that supplies refrigerant to the temperature control module 50 and a different chiller unit 55B. As a result, the moisture absorption module 70 can further lower the temperature of the refrigerant in the chiller unit 55B connected to the heat exchanger 71 with respect to the temperature of the refrigerant in the chiller unit 55A connected to the chuck device 45. . As a result, the moisture absorption capability of the inspection space 11 by the heat exchanger 71 can be further enhanced.

The inspection apparatus 1 according to the third modification shown in FIG. 6A includes a heater section 57 for heating the coolant in the temperature control module 50A, and heats the coolant supplied to the chuck device 45 . The heater section 57 is provided, for example, at an intermediate position of the supply path 53 for chuck. Even in this case, the temperature of the coolant supplied to the heat exchanger 71 of the moisture absorption module 70C can be relatively lowered with respect to the temperature of the chuck device 45 .

The inspection device 1 according to the fourth modified example shown in FIG. It is configured such that the refrigerant after circulating through the exchanger 71 is supplied to the chuck device 45 . Thereby, the inspection device 1 can reliably lower the temperature of the coolant in the heat exchanger 71 below the temperature of the chuck device 45 .

An inspection apparatus 1A according to a fifth modification shown in FIG. 7 has a plurality of (four in FIG. 7) testers 30, and each tester 30 inspects a wafer W. As shown in FIG. A plurality of testers 30 are arranged in an inspection space 11 that communicates along the horizontal direction (X-axis direction), forming a tester array 33 that shares this inspection space 11 . The inspection apparatus 1A may have a plurality of stages (for example, 2 to 4 stages) of the tester rows 33 along the vertical direction of the housing 10 .

Specifically, the inspection apparatus 1</b>A has an inspection section 100 having a plurality of testers 30 and a loader section 101 that transfers the wafer W to the inspection section 100 . A shutter 34 for opening and closing the transfer port is provided on the front surface of the room in which the testers 30 are arranged in the inspection section 100 . A cell control unit 35 for controlling each tester 30 is attached to the back of each tester 30 . Also, the inspection unit 100 is provided with one stage 40 that conveys the chuck device 45 to each tester 30 . The stage 40 has a moving part 41 (see FIG. 1) that can move in the inspection space 11 in three-dimensional directions.

The loader section 101 has a mounting table 102 , a loading/unloading section 103 , and a transfer chamber section 104 provided between the inspection section 100 and the loading/unloading section 103 . The mounting table 102 mounts a FOUP 102f, which is a container that accommodates a plurality of wafers W therein. The loading/unloading unit 103 includes a probe card loader 103a for loading/unloading the probe card 32, and an alignment unit 103b for alignment of the wafer W. As shown in FIG. Further, inside the carrying-in/out section 103, a controller 80 of the inspection apparatus 1A is provided. The transfer chamber section 104 has a transfer mechanism 105 that takes out the wafer W from the FOUP 102f, transfers it to the inspection section 100, and returns the wafer W inspected in the inspection section 100 to the FOUP 102F.

Furthermore, the inspection apparatus 1A includes a temperature control module 50 that supplies refrigerant to the inspection section 100 and discharges refrigerant gas from the inspection section 100 . The temperature control module 50 includes a chiller unit 55, chuck coolant paths 52 for supplying coolant to each chuck device 45, and channels of the chuck devices 45 prepared for each of the plurality of testers 30 and to which the chuck coolant paths 52 are connected. 51 (see FIG. 1).

The inspection apparatus 1</b>A includes a heat exchanger 71 as a moisture absorption module 70 that absorbs moisture in the inspection space 11 at a position near each of the plurality of chuck devices 45 . That is, the heat exchanger 71 is arranged for each individual tester 30 . The heat exchangers 71 in the same inspection space 11 are connected in series with each other, so that the refrigerant can be smoothly supplied from the chiller unit 55 to each heat exchanger 71 . Note that the heat exchangers 71 may be connected in parallel with each other.

Also, the moisture absorption module 70 shares the chiller unit 55 of the temperature control module 50 . The heat exchanger refrigerant path 72 branches from the chuck refrigerant path 52 and connects the heat exchangers 71 to each other. Each heat exchanger 71 is supplied with a coolant having a temperature lower than the temperature of the chuck device 45, thereby absorbing moisture in the inspection space 11 communicating in the X-axis direction. Alternatively, the heat exchanger 71 is not limited to being arranged for each of the plurality of testers 30 (chuck devices 45 ), and one or more heat exchangers 71 may be provided in the inspection space 11 . For example, the moisture absorption module 70 can have a configuration in which two heat exchangers 71 are provided in the inspection space 11 having four testers 30 .

The controller 80 of the inspection apparatus 1A can manage the dew point of each inspection space 11 in the same manner as in the above embodiment. As a result, the temperature of each heat exchanger 71 becomes lower than that of the chuck device 45, so that the gas in the inspection space 11 is frozen and the amount of water vapor in the inspection space 11 can be reduced. Therefore, in the inspection apparatus 1A as well, by lowering the dew point temperature of the inspection space 11 with the heat exchanger 71, it is possible to suppress the occurrence of dew condensation on each chuck device 45 and its surroundings.

The technical ideas and effects of the present disclosure described in the above embodiments will be described below.

A first aspect of the present disclosure is an inspection apparatus 1, 1A for inspecting an object to be inspected, which includes a housing 10 having an inspection space 11, an object to be inspected (wafer W ), temperature control modules 50, 50A, and 50B for supplying coolant to the chuck device 45 to adjust the temperature of the object to be inspected, and the chuck device 45 provided in the inspection space 11. has a dew point meter 13 for detecting the dew point temperature of the inspection space 11, and moisture absorption modules 70, 70A to 70D capable of adjusting the dew point temperature of the inspection space 11, and the moisture absorption modules 70, 70A to 70D are Based on the dew point temperature detected by the dew point meter 13 provided in the space 11, the moisture in the inspection space 11 is condensed or solidified by supplying coolant having a temperature lower than the temperature of the chuck device 45, and the dew point temperature of the inspection space 11 is adjusted. and a discharge portion 77 for discharging moisture condensed or solidified in the heat exchanger 71 .

According to the above, the inspection apparatuses 1 and 1A condense or solidify the moisture in the inspection space 11 by the heat exchanger 71 supplied with the coolant having a temperature lower than the temperature of the chuck device 45, thereby Moisture can be lowered. That is, the adsorption of moisture in the heat exchanger 71 lowers the dew point temperature of the inspection space 11, effectively preventing dew condensation on the chuck device 45 and the object to be inspected. As a result, the inspection apparatuses 1 and 1A can greatly reduce the amount of dry air that is discharged into the inspection space 11, and can reduce the energy consumption used to prevent dew condensation.

In addition, it has a control unit (controller 80) that acquires and processes information on the dew point temperature detected by the dew point meter 13, and the control unit compares the acquired dew point temperature information with the start threshold value Ts, The supply of refrigerant to the heat exchanger 71 is stopped when the temperature is equal to or lower than the start threshold Ts, while the supply of refrigerant to the heat exchanger 71 is started when the dew point temperature exceeds the start threshold Ts. As a result, the inspection apparatuses 1 and 1A can operate the heat exchanger 71 at an appropriate timing based on the dew point temperature detected by the dew point meter 13, and the moisture absorption by the heat exchanger 71 is realized, and the heat exchange is performed. Energy consumption associated with the operation of the device 71 can be suppressed as much as possible.

The heating unit 75 also includes a heating unit 75 that heats the heat exchanger 71 under the control of the control unit (controller 80) and melts the water solidified on the surface of the heat exchanger 71 to turn it into liquid water. Thereby, the inspection apparatuses 1 and 1A can reliably remove the frost (moisture) adsorbed on the heat exchanger 71 from the heat exchanger 71 .

In addition, the control unit (controller 80) acquires the dew point temperature while supplying the refrigerant to the heat exchanger 71, compares the acquired dew point temperature change tendency and the change threshold Tc, and determines that the change tendency is the change threshold Tc. The refrigerant supply to the heat exchanger 71 is continued in the following cases, and the refrigerant supply to the heat exchanger 71 is stopped and the heating unit 75 is operated when the changing tendency exceeds the change threshold value Tc. As a result, the inspection apparatus 1, 1A defrosts the heat exchanger 71 by the heating unit 75 when the moisture absorption ability (moisture adsorption ability) of the heat exchanger 71 is lowered, so that the moisture absorption by the heat exchanger 71 is reduced. can be stably performed again.

The discharge unit 77 includes a drain pipe 77b for discharging liquid water from the heat exchanger 71 and a pump (drainage pump 77p) provided in the drain pipe 77b. The liquid water generated by the heating of is sucked by a pump. As a result, the inspection apparatuses 1 and 1A can smoothly discharge liquid water from the heat exchanger 71 .

Further, the temperature control modules 50, 50A, and 50B have a chuck supply path 53 that supplies coolant to the chuck device 45, and a flow rate adjustment valve 56 provided in the chuck supply path 53. , 70A to 70D are provided in a heat exchanger supply path 73 for supplying refrigerant to the heat exchanger 71 and in the heat exchanger supply path 73, and are not interlocked with the flow rate adjustment valve 56 by a control unit (controller 80). and an on-off valve 76 that switches between supplying and stopping the supply of the refrigerant to the heat exchanger 71 by opening and closing the opening and closing. Thereby, the inspection apparatuses 1 and 1A can easily switch between supplying and stopping the supply of the coolant to the heat exchanger 71 regardless of the opening degree of the flow rate adjustment valve 56 of the chuck device 45 .

Also, the temperature control modules 50, 50A, 50B and the moisture absorption modules 70, 70A to 70D share the chiller unit 55 that supplies the refrigerant to the chuck device 45 and the heat exchanger 71. As shown in FIG. By sharing the hardware of the temperature control modules 50, 50A, 50B and the moisture absorption modules 70, 70A to 70D in this way, the simplification and miniaturization of the inspection apparatuses 1, 1A can be further promoted.

It also includes a pressure adjustment unit 60 that adjusts the inspection space 11 to a positive pressure. The pressure adjustment unit 60 allows the inspection apparatus 1 and 1A to keep the inspection space 11 at a positive pressure, thereby effectively suppressing the inflow of moisture into the inspection space 11 .

Also, a tester 30 is provided for electrically testing an object to be inspected (wafer W), and the temperature control modules 50, 50A, and 50B adjust the temperature of the object to be inspected to −30° C. or less during inspection by the tester 30. . As a result, the inspection apparatuses 1 and 1A can stably perform an electrical inspection in a low-temperature environment while preventing dew condensation on the chuck device 45 and the object to be inspected.

A second aspect of the present disclosure is a dew point management method for managing the dew point of inspection apparatuses 1 and 1A that inspect an object to be inspected. an object 10, a chuck device 45 that is provided in the inspection space 11 and holds the object to be inspected (wafer W), and temperature control modules 50 and 50A that supply coolant to the chuck device 45 to adjust the temperature of the object to be inspected. , 50B, a dew point meter 13 which is provided in the inspection space 11 in which the chuck device 45 is arranged and which detects the dew point temperature of the inspection space 11, and moisture absorption modules 70, 70A which can adjust the dew point temperature of the inspection space 11. 70D, and in the dew point control method, a coolant having a temperature lower than the temperature of the chuck device 45 is supplied to the heat exchanger 71 provided in the inspection space 11 based on the dew point temperature detected by the dew point meter 13. to condense or solidify moisture in the inspection space 11 to adjust the dew point temperature of the inspection space 11; As described above, the dew point control method according to the second aspect can also reduce the energy consumption used to prevent dew condensation on the chuck device 45 and the object to be inspected.

The inspection apparatuses 1 and 1A and the dew point management method according to the embodiments disclosed this time are illustrative in all respects and are not restrictive. Embodiments are capable of variations and modifications in various forms without departing from the scope and spirit of the appended claims. The items described in the above multiple embodiments can take other configurations within a consistent range, and can be combined within a consistent range.

1, 1A Inspection device 10 Case 11 Inspection space 13 Dew point meter 45 Chuck device 50, 50A, 50B Temperature control module 70, 70A to 70D Moisture absorption module 71 Heat exchanger 77 Discharge part W Wafer

Claims (10)

An inspection device for inspecting an object to be inspected,
a housing having an inspection space;
a chuck device provided in the inspection space and holding the object to be inspected;
a temperature control module that supplies a coolant to the chuck device to adjust the temperature of the object to be inspected;
a dew point meter provided in the inspection space for detecting the dew point temperature of the inspection space;
a moisture absorption module capable of adjusting the dew point temperature of the inspection space;
The moisture absorption module is provided in the inspection space, and based on the dew point temperature detected by the dew point meter, supplies a coolant having a temperature lower than the temperature of the chuck device to condense or solidify moisture in the inspection space. a heat exchanger for adjusting the dew point temperature of the examination space;
a discharge unit for discharging moisture condensed or solidified in the heat exchanger,
inspection equipment. Having a control unit that acquires and processes information on the dew point temperature detected by the dew point meter,
The control unit compares the acquired dew point temperature information with a start threshold, and stops the supply of the refrigerant to the heat exchanger when the dew point temperature is equal to or lower than the start threshold, while the dew point temperature exceeds the initiation threshold, initiating the supply of the refrigerant to the heat exchanger;
The inspection device according to claim 1. A heating unit that heats the heat exchanger under the control of the control unit and dissolves water solidified on the surface of the heat exchanger to form liquid water,
The inspection device according to claim 2. The control unit acquires the dew point temperature while the refrigerant is being supplied to the heat exchanger, compares the acquired tendency of change in the dew point temperature with a change threshold,
Continue supplying the refrigerant to the heat exchanger when the trend of change is equal to or less than the threshold of change, and stop supplying the refrigerant to the heat exchanger when the trend of change exceeds the threshold of change to perform the heating. operate the department,
The inspection device according to claim 3. The discharge unit is
a drain pipe for discharging the liquid water from the heat exchanger, and a pump provided in the drain pipe,
The control unit sucks the liquid water generated by the heating of the heating unit by the pump.
The inspection device according to claim 3 or 4. The temperature control module has a chuck supply path for supplying the coolant to the chuck device, and a flow control valve provided in the chuck supply path,
The moisture absorption module is provided in a heat exchanger supply path for supplying the refrigerant to the heat exchanger and in the heat exchanger supply path, and is opened and closed by the control unit without being interlocked with the flow rate adjustment valve. an on-off valve that switches between supplying and stopping the supply of the refrigerant to the heat exchanger,
The inspection device according to any one of claims 2 to 5. The temperature control module and the moisture absorption module share a chiller unit that supplies the refrigerant to the chuck device and the heat exchanger.
The inspection device according to any one of claims 1 to 6. A pressure adjustment unit that adjusts the test space to a positive pressure,
The inspection device according to any one of claims 1 to 7. Having a tester for performing an electrical test of the device under test,
The temperature control module adjusts the temperature of the device under test to −30° C. or less during testing by the tester.
The inspection device according to any one of claims 1 to 8. A dew point management method for managing the dew point of an inspection device that inspects an object to be inspected,
The inspection device is
a housing having an inspection space;
a chuck device provided in the inspection space and holding the object to be inspected;
a temperature control module that supplies a coolant to the chuck device to adjust the temperature of the object to be inspected;
a dew point meter provided in the inspection space for detecting the dew point temperature of the inspection space;
a moisture absorption module capable of adjusting the dew point temperature of the inspection space;
In the dew point management method,
Based on the dew point temperature detected by the dew point meter, a coolant having a temperature lower than the temperature of the chuck device is supplied to the heat exchanger provided in the inspection space to condense or solidify moisture in the inspection space. , adjusting the dew point temperature of the examination space;
discharging moisture condensed or solidified in the heat exchanger by a discharge section;
Dew point control method.

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