Temperature calibration system, inspection device, and temperature calibration method

Abstract

To provide a technique enabling calibrating measurement values of a plurality of temperature sensors provided on a loading unit with high accuracy.SOLUTION: A temperature calibration system includes: an inspection device which adjusts a temperature of an inspection object body loaded on a loading unit to inspect the inspection object body; and a surface thermometer, so as to perform the calibration of a plurality of temperature sensors provided on the loading unit. The inspection device includes: a movement unit which can move the loading unit in an X-axis direction, a Y-axis direction, and a Z-axis direction; and a control unit which performs calibration processing on measurement values of the plurality of temperature sensors. The surface thermometer contacts with the loading surface of the loading unit to detect a surface temperature of the loading surface. The control unit controls the movement unit to make the surface thermometer contact with a detection position of the loading surface of the loading unit, to detect the surface temperature of the detection position by the surface thermometer, so as to calibrate, based on the surface temperature, a measurement value of a temperature sensor corresponding to the detection position.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a temperature calibration system, an inspection device, and a temperature calibration method. [Background technology]

[0002] Inspection equipment for performing electrical inspection of wafers as test objects holds and transports wafers using a chuck provided on the mounting section of a probe device. This type of inspection equipment is known to measure the temperature of the mounting surface of the mounting section on which the wafer is mounted using a temperature sensor, and adjust the temperature of the mounting surface using a heater (temperature control mechanism) in the chuck.

[0003] For example, Patent Document 1 discloses an apparatus having a plurality of resistance thermometers (temperature sensors) provided on a substrate (wafer) placed on a mounting section, and a control section that measures the resistance value (temperature) of the resistance thermometers on the substrate via a probe and adjusts the temperature of a heater in the mounting section. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-231040 Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure provides a technique that can accurately calibrate the measurement values ​​of a plurality of temperature sensors provided on a mounting section. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, there is provided a temperature calibration system comprising an inspection device that adjusts the temperature of an object to be inspected placed on a mounting portion to inspect the object to be inspected, and a surface thermometer, and that calibrates multiple temperature sensors provided on the mounting portion, wherein the inspection device comprises a moving unit that can move the mounting portion in the X-axis, Y-axis, and Z-axis directions, and a control unit that performs a calibration process on the measurement values ​​of the multiple temperature sensors, wherein the surface thermometer contacts the mounting surface of the mounting portion to detect the surface temperature of the mounting surface, and the control unit controls the moving unit to bring the surface thermometer into contact with a detection position on the mounting surface of the mounting portion, detects the surface temperature at the detection position using the surface thermometer, and calibrates the measurement value of the temperature sensor corresponding to the detection position based on the surface temperature. [Effects of the Invention]

[0007] According to one aspect, the measurement values ​​of the plurality of temperature sensors provided on the mounting portion can be calibrated with high accuracy. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a horizontal cross-sectional view showing an example of an inspection device according to a first embodiment. [Figure 2] 2 is a cross-sectional view of the inspection device taken along line II-II in FIG. 1. [Figure 3] 2 is a cross-sectional view of the inspection device of FIG. 1 taken along the Y-axis direction. [Figure 4] FIG. 2 is a schematic explanatory diagram showing a prober provided in each testing space. [Figure 5] FIG. 2 is a perspective view showing the configuration of a chuck provided in the prober. [Figure 6] FIG. 2 is a schematic plan view showing the installation state of each temperature sensor of the chuck. [Figure 7] FIG. 1 is an explanatory diagram showing a temperature calibration system. [Figure 8] FIG. 2 is a cross-sectional view showing a surface thermometer of the jig and its surrounding structure. [Figure 9] FIG. 1 is a block diagram illustrating the calibration of a surface thermometer of a temperature calibration system. [Figure 10]FIG. 2 is a block diagram showing functional blocks of a prober control unit. [Figure 11] 1 is a first flowchart showing the processing flow of a temperature calibration method. [Figure 12] 10 is a second flowchart showing the processing flow of the temperature calibration method. [Figure 13] FIG. 10 is a schematic plan view of a chuck of a temperature calibration system according to a second embodiment. [Figure 14] 10 is a flowchart showing a processing flow of a sensor failure detection method. [Figure 15] FIG. 10 is a schematic explanatory diagram showing an inspection device equipped with a temperature calibration system according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0010] [First embodiment] Fig. 1 is a horizontal cross-sectional view showing an example of an inspection device 1 according to a first embodiment. Fig. 2 is a cross-sectional view of the inspection device 1 of Fig. 1 taken along line II-II. Fig. 3 is a cross-sectional view of the inspection device 1 of Fig. 1 taken along the Y-axis direction.

[0011] As shown in Fig. 1, the inspection device 1 is an apparatus that performs electrical inspection on a semiconductor substrate (wafer W), which is an example of an object to be inspected. The inspection device 1 is placed, for example, in a clean room of a factory that manufactures wafers W. The inspection device 1 has an inspection unit 10 having a plurality of inspection chambers 11, and a loader unit 20 that transports wafers W to the inspection unit 10. The inspection unit 10 and the loader unit 20 are connected in the Y-axis direction.

[0012] The multiple inspection chambers 11 of the inspection section 10 are separated from one another by partition walls 12. The inspection section 10 includes an inspection unit 40 in each of the multiple inspection chambers 11, and electrical inspection of the wafers W is performed in each inspection unit 40. In addition, a transfer port 13 for transferring the wafers W between the loader section 20 and each inspection chamber 11 is provided at the front (positive Y-axis direction) of each inspection chamber 11, and a shutter 14 for opening and closing the transfer port 13 is provided. A cell control unit 15 is provided at the back (negative Y-axis direction) of each inspection chamber 11, communicating with each inspection chamber 11 and controlling each inspection unit 40. The cell control unit 15 includes, for example, a solenoid, a vacuum sensor, an electro-pneumatic regulator, an E-IOM board, a temperature controller, etc. (all not shown).

[0013] The loader section 20 has a mounting table 21, a loading / unloading section 22, and a transfer chamber section 23 provided between the inspection section 10 and the loading / unloading section 22. The mounting table 21 mounts a FOUP 21f, which is a container for accommodating a plurality of wafers W. The loading / unloading section 22 has a probe card loader 25 for loading and unloading a probe card 24 (see FIG. 3), and an alignment section 26 for aligning the wafer W. The probe card loader 25 and the alignment section 26 are adjacent to each other along the X-axis direction. In addition, a control unit 9 of the inspection apparatus 1 is provided inside the loading / unloading section 22. The transfer chamber section 23 has a transfer mechanism 27 for transferring the wafer W.

[0014] Furthermore, the inspection device 1 includes a refrigerant unit 30 that supplies a refrigerant to the inspection unit 10 and discharges the refrigerant from the inspection unit 10. The refrigerant unit 30 has a refrigerant pipe 31, a refrigerant output unit 32 that supplies a refrigerant to the refrigerant pipe 31, a heat exchanger 33 that adjusts the temperature of the refrigerant, and an exhaust heat treatment unit 34 that treats the refrigerant discharged from the inspection unit 10. The refrigerant pipe 31 extends between the outside of the inspection device 1 and the inside of the housing 2 of the inspection device 1, and is connected to the refrigerant output unit 32, the heat exchanger 33, and the exhaust heat treatment unit 34.

[0015] 2, the inspection section 10 includes an inspection chamber row 16 in which four inspection chambers 11 are lined up along the X-axis direction, and these inspection chamber rows 16 are arranged in three stages along the Z-axis direction (vertical direction). In other words, the inspection device 1 has 12 inspection chambers 11, and an inspection unit 40 is provided for each of these inspection chambers 11.

[0016] Each row of inspection chambers 16 has four inspection chambers 11 connected in the X-axis direction by cutting out a portion of the partition wall 12, thereby forming a single, substantially sealed inspection space 17. That is, the inspection section 10 has an upper inspection space 17a, a middle inspection space 17b, and a lower inspection space 17c, corresponding to the rows of inspection chambers 16 in the Z-axis direction. Refrigerant piping spaces 18, in which refrigerant piping 31 of the refrigerant section 30 is disposed, are formed between the upper inspection space 17a and the middle inspection space 17b, between the middle inspection space 17b and the lower inspection space 17c, and below the lower inspection space 17c. The refrigerant piping 31 of the refrigerant piping space 18 is disposed in one space corresponding to each of the upper inspection space 17a, the middle inspection space 17b, and the lower inspection space 17c, and connects the four inspection units 40 in each row of inspection chambers 16 in series.

[0017] Each of the upper inspection space 17a, the middle inspection space 17b, and the lower inspection space 17c is provided with a prober 50 (stage) that is movable in the X-axis direction. The prober 50 is provided below each inspection unit 40 in the row of inspection chambers 16, and transports wafers W to each inspection unit 40 lined up in the X-axis direction. Each of the upper inspection space 17a, the middle inspection space 17b, and the lower inspection space 17c is also provided with an alignment camera 19 that is movable along the X-axis direction.

[0018] 3, the transfer mechanism 27 of the transfer chamber section 23 is movable in the X-axis direction and the Z-axis direction in correspondence with the plurality of inspection chambers 11 arranged in a matrix. The transfer mechanism 27 includes a transfer arm 271 that supports the wafer W, a rotation drive unit 272 that rotates the transfer arm 271, and a base section 273 that supports the rotation drive unit 272.

[0019] The transfer mechanism 27 receives the uninspected wafer W from the FOUP 21f and delivers the wafer W to the prober 50 on each stage, and receives the inspected wafer W and returns it to the FOUP 21f, by moving the transfer arm 271 back and forth in the Y-axis direction and rotating in the θ-axis direction. Furthermore, the transfer mechanism 27 transfers the probe card 24 requiring maintenance from each inspection unit 40 to the probe card loader 25, and transfers a new or maintained probe card 24 to each inspection unit 40.

[0020] Each inspection unit 40 provided in each inspection chamber 11 has a tester 41, a probe card 24, and a bellows 42. The tester 41 supports the probe card 24 via a support plate (not shown) and transmits inspection signals to multiple devices formed on the wafer W via a contact block (not shown) and multiple probes 24a of the probe card 24. The bellows 42 hangs down from the support plate so as to surround the probe card 24, and forms an airtight space including the probe card 24 and the wafer W with the multiple probes 24a in contact with the wafer W placed on a chuck 70 of the prober 50. The inspection unit 40 vacuums the airtight space surrounded by the bellows 42 via a vacuum line (not shown), thereby adsorbing the probe card 24 and the chuck 70 to the support plate.

[0021] FIG. 4 is a schematic explanatory diagram showing a prober 50 provided in each inspection space 17. As shown in FIG. 4, the inspection device 1 includes a frame structure 51 that constitutes the inspection section 10 and supports the prober 50. The prober 50 installed on the frame structure 51 transports the wafer W in the X-axis, Y-axis, and Z-axis directions. The prober 50 includes a movement section 56 (an X-axis movement mechanism 57, a Y-axis movement mechanism 58, and a Z-axis movement mechanism 59), a chuck 70, a prober control section 80, and a motor driver 90. The chuck 70 holds the wafer W on its upper surface by an appropriate holding means (vacuum suction, mechanical chuck, electrostatic suction, etc.).

[0022] The frame structure 51 has a two-tiered structure including an upper base 52 that supports a moving unit 56, a lower base 53 that supports a prober control unit 80 and a motor driver 90, and a plurality of support columns 54 provided at the four corners of the upper base 52 and the lower base 53. For example, the space above the upper base 52 is arranged as an inspection space 17, and the space between the upper base 52 having the prober control unit 80 and the lower base 53 is arranged as a refrigerant piping space 18.

[0023] X-axis movement mechanism 57 of movement unit 56 includes a plurality of guide rails 57a fixed to the upper surface of upper base 52 and extending along the X-axis direction, and X-axis movable body 57b arranged across each guide rail 57a. X-axis movable body 57b has an X-axis operating unit (not shown, including a motor and a gear mechanism) inside, and this X-axis operating unit is connected to motor driver 90. X-axis movable body 57b reciprocates in the X-axis direction based on the power supply from motor driver 90.

[0024] Similarly, Y-axis movement mechanism 58 includes a plurality of guide rails 58a fixed to the upper surface of X-axis movable body 57b and extending along the Y-axis direction, and Y-axis movable body 58b arranged across each guide rail 58a. Y-axis movable body 58b also has a Y-axis operating unit (motor, gear mechanism, etc.) inside, not shown, and this Y-axis operating unit is connected to motor driver 90. Y-axis movable body 58b reciprocates in the Y-axis direction based on the power supply from motor driver 90.

[0025] Z-axis movement mechanism 59 is installed on Y-axis movable body 58b, and is releasably engaged with chuck 70 at its upper portion. Z-axis movement mechanism 59 moves chuck 70 in the Z-axis direction (vertical direction), thereby raising and lowering wafer W placed on chuck 70.

[0026] The prober 50 configured in this manner moves the chuck 70 to the desired three-dimensional position by supplying appropriate power to each of the X-axis movement mechanism 57, Y-axis movement mechanism 58, and Z-axis movement mechanism 59 from the motor driver 90, which receives commands from the prober control unit 80.

[0027] 5 is a perspective view showing the configuration of a chuck 70 provided in the prober 50. As shown in FIG. 5, the chuck 70 is formed in a disk shape according to the shape of the wafer W to be placed thereon. The chuck 70 according to this embodiment supports the wafer W by vacuum suction and also has the function of regulating the temperature of the wafer W. Specifically, the chuck 70 is configured by stacking a base plate 71, a spacer 72, a temperature regulation mechanism 73, a soaking plate 74, and a top plate 75 in this order from bottom to top in the vertical direction.

[0028] The base plate 71 is provided at the bottom layer, and mounts the chuck 70 to the Z-axis moving mechanism 59. A suction channel (not shown) for vacuum-suctioning the wafer W is provided inside the base plate 71, and this suction channel is connected to a suction mechanism 64 (see FIG. 4) provided inside the Z-axis moving mechanism 59. The suction channel also communicates with a plurality of holes 76 formed in the upper surface of the base plate 71. Each of the holes 76 also penetrates the temperature adjustment mechanism 73 and the soaking plate 74, and communicates with a suction recess 75a in the top plate 75. In other words, the suction mechanism 64 applies negative pressure to the top plate 75 via the suction channel and each hole 76, thereby holding the wafer W on the top plate 75.

[0029] The spacer 72 is formed in a ring shape that surrounds the outer periphery of the base plate 71 at a position facing the base plate 71 , and forms a heat insulating space between the base plate 71 and the temperature adjustment mechanism 73 .

[0030] The temperature adjustment mechanism 73 has a disk-shaped jacket 731, and a refrigerant flow path and a heater (neither of which are shown) provided within the jacket 731. The jacket 731 has refrigerant ports 732, to which refrigerant pipes 31 of the refrigerant unit 30 are connected, at predetermined locations on the outer periphery. The refrigerant flow path communicates with the refrigerant ports 732, and extends in a circular, serpentine, or spiral shape along the surface direction (horizontal direction) of the jacket 731. The refrigerant flow path circulates the refrigerant within the jacket 731 based on the flow of refrigerant from the refrigerant pipes 31 connected to the refrigerant ports 732, thereby cooling the entire jacket 731.

[0031] The heater is, for example, an electric heating wire, and is arranged between or above the refrigerant flow paths in the jacket 731, extending in a circular, serpentine, or spiral shape along the surface direction of the jacket 731. The heater is electrically connected to a temperature controller (not shown) of the prober control unit 80, and heats the jacket 731 when power is supplied from the prober control unit 80. The temperature controller adjusts the temperature of the heater to a target temperature using, for example, a PID control circuit.

[0032] Furthermore, the temperature adjustment mechanism 73 can individually adjust the temperature of multiple regions in a plan view of the chuck 70. For example, the temperature adjustment mechanism 73 divides the flat circular chuck 70 into four regions at approximately 90° intervals, and provides heaters and coolant channels independently in each region. This allows the prober control unit 80 to adjust the temperature of each of the four regions using the temperature adjustment mechanism 73.

[0033] The heat equalizing plate 74 is made of a material (for example, ceramic) having an appropriate thermal conductivity. The heat equalizing plate 74 uniformly transfers the temperature adjusted by the temperature adjustment mechanism 73 (jacket 731) to the top plate 75.

[0034] The top plate 75 is formed in a disk shape that is thicker than the soaking plate 74, and has a mounting surface 751 on its upper surface on which the wafer W is placed. Adsorption recesses 75a are formed in this mounting surface 751. The top plate 75 is provided with a plurality of temperature sensors 77 on the opposite side (back side) of the mounting surface 751 to the mounting surface 751, for measuring the temperature of the mounting surface 751 (in other words, the temperature of the wafer W placed on the mounting surface 751). In the case of a chuck 70 configured to electrostatically adsorb the wafer W, the mounting surface 751 may be formed flat.

[0035] By providing multiple temperature sensors 77, the prober 50 recognizes the temperature distribution on the mounting surface 751 and improves the accuracy of temperature control by the temperature adjustment mechanism 73. The type of each temperature sensor 77 is not particularly limited, but it is preferable to use, for example, a resistance temperature detector (RTD) type sensor. The resistance temperature detector may be a thermistor, a thermocouple, an optical temperature sensor, or a semiconductor temperature sensor.

[0036] Each temperature sensor 77 is electrically connected to a temperature sensor substrate 78 (see FIG. 4) and transmits a measurement value to the temperature sensor substrate 78. The temperature sensor substrate 78 is fixed to a position to the side of the location where the chuck 70 and the Z-axis movement mechanism 59 are connected, and is communicatively connected to a prober control unit 80. When the inspection device 1 inspects the wafer W, the temperature sensor substrate 78 automatically switches between measurements of the multiple temperature sensors 77, measures the temperature with the switched temperature sensor 77, and transmits the received measurement result to the prober control unit 80.

[0037] Fig. 6 is a schematic plan view showing the installation state of each temperature sensor 77 of the chuck 70. Fig. 6(a) shows an example of the arrangement of each temperature sensor 77 according to this embodiment, Fig. 6(b) shows an example of the temperature distribution of the chuck 70 when each temperature sensor 77 is applied, and Fig. 6(c) shows an example of the temperature distribution of the chuck 70 when one temperature sensor 77' shown as a reference example is applied. As shown in Fig. 6(a), the multiple temperature sensors 77 are set in an appropriate number and installation positions that allow the temperature distribution of the entire mounting surface 751 of the top plate 75 to be measured.

[0038] As an example, in a plan view of the top plate 75, 12 of the temperature sensors 77 are provided at equal intervals around an imaginary outer circle io, and four of the temperature sensors 77 are provided at equal intervals around an imaginary inner circle ii that is located inside the imaginary outer circle io. Another one of the temperature sensors 77 is provided at a predetermined position outside the imaginary outer circle io (on the outer periphery of the top plate 75 on the Y-axis direction side). That is, the top plate 75 has a total of 17 temperature sensors 77.

[0039] Here, as shown in FIG. 6( c), in a configuration in which one temperature sensor 77′ is provided on the chuck 70, the single temperature sensor 77′ measures the temperature only around the installation location on the top plate 75. In this case, even if there is variation in the temperature distribution on the mounting surface 751, the temperature adjustment mechanism 73 of the prober 50 controls the operation of the cooling medium unit 30 or the heater based on the temperature around the installation location of the temperature sensor 77′ to adjust the temperature. For example, the mounting surface 751 of the chuck 70 may be partially heated due to heat generated by the device itself on the wafer W during inspection. In particular, when inspecting the wafer W at high speed, the amount of heat generated increases, making it easier for the temperature of the mounting surface 751 to partially rise. Therefore, a chuck 70 with one temperature sensor 77′ may have a concern that the accuracy of temperature control by the temperature adjustment mechanism 73 may be reduced.

[0040] 6(b), by providing a plurality of temperature sensors 77 as in the chuck 70 according to this embodiment, the prober control unit 80 can accurately recognize the temperature distribution of the mounting surface 751 based on the measurement results of each temperature sensor 77. For example, when the target temperature of the mounting surface 751 is set to 85°C, each temperature sensor 77 measures high-temperature spots on the mounting surface 751 using the temperature sensor substrate 78. By using the measurement values ​​of each temperature sensor 77, the prober control unit 80 can effectively control the temperature adjustment mechanism 73 so that the entire mounting surface 751 approaches the target temperature.

[0041] 6(a), the temperature sensors 77 near channel numbers 1, 12, and 17 correspond to temperature sensors 77 in a location (stable region SA) where the temperature is likely to stabilize on the chuck 70. The location where the temperature is likely to stabilize means that the temperature adjustment response of the temperature adjustment mechanism 73 is faster (higher) than other locations, due to the location being near the refrigerant inlet of the refrigerant flow path or near the input of a PID-controlled heater. In other words, in the temperature adjustment of the temperature adjustment mechanism 73, the temperature sensor substrate 78 detects the temperature of the temperature sensor 77 in the stable region SA (e.g., channel number 1) first among the multiple temperature sensors 77, thereby making it easier to monitor the temperature of the mounting surface 751.

[0042] It goes without saying that the number and installation positions of the temperature sensors 77 on the chuck 70 are not particularly limited, as long as two or more temperature sensors 77 are provided, and the installation positions may also be designed appropriately depending on the positions of the refrigerant flow path, the heater, etc. The types of the temperature sensors 77 provided on the chuck 70 may be the same or different.

[0043] The prober control unit 80 is connected to the control unit 9 of the inspection apparatus 1 and controls the operation of the prober 50 based on commands from the control unit 9. The prober control unit 80 includes, for example, a main controller that controls the overall operation of the prober 50, a PLC that controls the operation of the moving unit 56, a temperature controller that controls the temperature adjustment mechanism 73, an illumination control unit, a power supply unit, and the like (all not shown). The main controller of the prober control unit 80 may be a built-in prober computer board that includes one or more processors, memory, input / output interfaces, and electronic circuits (not shown). The one or more processors may be one or a combination of a CPU, ASIC, FPGA, and circuits consisting of multiple discrete semiconductors, and execute programs and recipes stored in memory. The memory includes non-volatile memory and volatile memory and forms the storage unit of the prober control unit 80.

[0044] After the prober control unit 80 receives the wafer W from the transfer mechanism 27 onto the chuck 70 on the prober 50, it moves the moving unit 56 horizontally (in the X and Y axes) to align the wafer W so that it faces the probe card 24 of a predetermined testing unit 40. After alignment, the prober control unit 80 causes the prober 50 to raise the chuck 70 and bring the wafer W into contact with the probes 24a of the probe card 24. While maintaining this contact state between the wafer W and the probes 24a, the control unit 9 of the testing device 1 evacuates the sealed space surrounded by the bellows 42 to adsorb the chuck 70 to the support plate. In this state, the control unit 9 starts an electrical test using the tester 41. After the tester 41 has finished testing, the prober control unit 80 performs the reverse operation of the above to lower and horizontally move the inspected wafer W and return the wafer W to the transfer mechanism 27.

[0045] The inspection apparatus 1 described above requires calibration of the multiple temperature sensors 77 provided on the chuck 70. Next, a temperature calibration system 100 that calibrates each temperature sensor 77 will be described with reference to FIGS. 7 and 8. FIG. 7 is an explanatory diagram showing the temperature calibration system 100, where (a) is a schematic side view of the system and (b) is a perspective view showing a jig 110. FIG. 8 is a cross-sectional view showing a surface thermometer 120 of the jig 110 and its surrounding structure, where (a) shows a state in which the surface thermometer 120 is not in contact with the mounting surface 751 and (b) shows a state in which the surface thermometer 120 is in contact with the mounting surface 751.

[0046] The temperature calibration system 100 according to this embodiment utilizes a prober 50 that actually uses the measurement values ​​of the temperature sensors 77 in order to calibrate the measurement values ​​measured by each temperature sensor 77. In addition to the prober 50, the temperature calibration system 100 also includes a jig 110 that is fixed to the frame structure 51 and has a surface thermometer 120 that detects the temperature of the mounting surface 751 of the chuck 70, and a data logger 130 that records the detection results of the surface thermometer 120.

[0047] The jig 110 has a surface thermometer 120 disposed above the chuck 70. The jig 110 according to this embodiment is formed in an H-shape in a plan view and has a pair of rod portions 111 that can be placed on the multiple support columns 54 of the frame structure 51, and a bridging portion 112 that bridges the center portions of the pair of rod portions 111 in the extension direction. The jig 110 is formed of a metal frame such as aluminum. The surface thermometer 120 is fixed to the center portion of the bridging portion 112 of the jig 110 in the extension direction.

[0048] The jig 110 has a fixing block 113 on the bridge portion 112 for fixing the surface thermometer 120. The fixing block 113 is attached to the jig 110 so that its position can be adjusted along the surface direction (horizontal direction) of the frame structure 51. The fixing block 113 supports the surface thermometer 120 via a support bar 114 at a portion that protrudes laterally from the bridge portion 112.

[0049] The fixed block 113 and the support bar 114 form a relief structure 115 that holds the surface thermometer 120 so that it can be displaced in the vertical direction (Z-axis direction). This relief structure 115 has the function of absorbing the pressing force when the surface thermometer 120 contacts the mounting surface 751 by restricting horizontal displacement of the surface thermometer 120 with respect to the jig 110 while allowing the surface thermometer 120 to move upward relative to the jig 110. For example, the fixed block 113 has a through hole 113h through which the support bar 114 is disposed, and a step 116 is formed on the inner circumferential surface that constitutes this through hole 113h. Meanwhile, the support bar 114 has a flange 114f that can be caught on the step 116. The upper part of the through hole 113h is formed with an inner diameter that allows the flange 114f to move, and a retaining member 125 is provided. The through-hole 113h of the support bar 114 allows the fixed block 113 to move upward, and the engagement between the flange 114f and the step 116 prevents the fixed block 113 from falling off downward.

[0050] The surface thermometer 120 is connected to the lower end of the fixed block 113 and is suspended vertically by the jig 110. The surface thermometer 120 has a cylindrical case 121 that extends vertically, and is provided with a detection unit 122 below the case 121. The detection unit 122 includes a contact body 123 that is connected to the case 121, and a detector 124 that is in direct contact with the mounting surface 751 of the chuck 70 within the contact body 123.

[0051] The contact body 123 is made of a resin material such as polyimide, and has a flat lower end surface facing the mounting surface 751. The contact body 123 has a ring-like (cylindrical) shape that is flush with the outer circumferential surface of the case 121, and a flat circular cavity is provided inside the contact body 123 in which the detector 124 is placed. The contact body 123 has higher thermal insulation properties than the detector 124, thereby reducing heat loss and improving the detection accuracy of the detector 124.

[0052] A K-type thermocouple formed in a thin plate shape can be used as the detector 124. Both ends of the detector 124 are fixed to the connecting surfaces of the contact body 123 of the case 121, and the detector 124 is formed in a mountain shape, curving downward from both ends to the middle part. The plate thickness of the detector 124 is formed to be significantly thinner (for example, 1 / 10 or less) than the thickness of the contact body 123 in the radial direction. The detector 124 formed in this way has a small heat capacity and a fast thermal response when it comes into contact with the mounting surface 751.

[0053] Furthermore, when the portion of the contact body 123 protruding from the lower end surface hits the mounting surface 751 of the chuck 70, the detector 124 easily elastically deforms upward and laterally to come into surface contact with the mounting surface 751. When the contact body 123 is in contact with the mounting surface 751, the detector 124 can always be in contact with the mounting surface 751 with the same contact area. That is, the detector 124 can detect the temperature in the same detection mode even if temperature detection is performed multiple times (reproducibility is guaranteed).

[0054] Fig. 9 is a block diagram showing the calibration of the surface thermometer 120 of the temperature calibration system 100. As shown in Fig. 9, the temperature detected by the surface thermometer 120 according to this embodiment is calibrated based on a standard 200 that has been previously calibrated to conform to a national standard (international standard). For example, the surface thermometer 120 is connected to the standard 200 of a calibration service organization that periodically performs calibration to conform to the national standard, and is calibrated so that the temperature calibration curve of the surface thermometer 120 and the temperature calibration curve of the standard 200 match (trace the national standard).

[0055] Since the jig 110 has one surface thermometer 120 for each of the multiple temperature sensors 77 provided on the chuck 70, the surface thermometer 120 itself can be calibrated using the standard 200 in a short time. Furthermore, it is preferable to calibrate the surface thermometer 120 periodically (for example, about once a year). The surface thermometer 120 calibrated in this manner has the same temperature compensation as the standard 200 (i.e., the national standard).

[0056] The data logger 130 is a computer having a processor, memory, and input / output interface (none of which are shown), and stores the surface temperature detected by the surface thermometer 120. The memory includes volatile memory and non-volatile memory (storage media such as computer storage media, flexible disks, compact disks, hard disks, magneto-optical disks, and memory cards), and constitutes the storage unit of the data logger 130. The data logger 130 is connected to the surface thermometer 120 and also to the prober control unit 80.

[0057] The temperature calibration system 100 calibrates each temperature sensor 77 before shipping the prober 50 (inspection device 1). In this calibration, the temperature calibration system 100 brings a surface thermometer 120 into contact with a detection position on the mounting surface 751 that overlaps with the multiple temperature sensors 77, and detects the surface temperature of the mounting surface 751. The data logger 130 acquires position information of the detection position on the mounting surface 751 facing the surface thermometer 120 from the prober control unit 80, acquires the surface temperature from the surface thermometer 120, and stores the position information of the detection position, the surface temperature, and time information in association with each other in memory.

[0058] The prober control unit 80 then acquires the position information of the detection position, the surface temperature, and the time information accumulated in the data logger 130 as calibration information, and calibrates each temperature sensor 77 of the chuck 70 using this calibration information. Note that the temperature calibration system 100 may be configured so that the prober control unit 80 directly acquires the surface temperature detected by the surface thermometer 120, without including the data logger 130. By calibrating each temperature sensor 77, the prober control unit 80 can match the measurement value of a given temperature sensor 77 to the surface temperature detected by the surface thermometer 120.

[0059] Fig. 10 is a block diagram showing the functional blocks of the prober control unit 80. For calibrating each temperature sensor 77, the prober control unit 80 includes a temperature adjustment control unit 81, a movement control unit 82, a surface temperature acquisition unit 83, a temperature measurement value acquisition unit 84, a correction value calculation unit 85, a calibration curve calculation unit 86, and a confirmation unit 87, as shown in Fig. 10.

[0060] The temperature control unit 81 controls the temperature control mechanism 73 (refrigerant unit 30, heater) of the prober 50 to set the temperature of the chuck 70 to a reference temperature set in the calibration of each temperature sensor 77. This reference temperature is not particularly limited, but may be, for example, one of three types: -55°C, 25°C, and 150°C.

[0061] The movement control unit 82 outputs a control command to the motor driver 90 and controls the operation of the movement unit 56 of the prober 50 via the motor driver 90. When calibrating each temperature sensor 77, the movement control unit 82 brings the surface thermometer 120 into contact with a detection position on the mounting surface 751 that overlaps a predetermined one of the temperature sensors 77. For example, the movement control unit 82 has position information for each temperature sensor 77 in advance, and calculates the movement distance and movement direction from one temperature sensor 77 to another based on the position information, and controls the movement unit 56 to move along the calculated movement distance and movement direction.

[0062] When calibrating each temperature sensor 77, it is preferable that the movement control unit 82 sequentially performs the calibration process on the temperature sensors 77 that are close to each other. For example, the movement control unit 82 performs the temperature calibration (detection of the temperature of the mounting surface 751) of each temperature sensor 77 in the order of the channel numbers assigned to the temperature sensors 77 in Fig. 6(a). This can shorten the movement time of the prober 50 in the temperature calibration method, and can shorten the time required for calibration.

[0063] 10, the surface temperature acquisition unit 83 acquires the surface temperatures of each temperature sensor 77 detected by the surface thermometer 120 from the data logger 130 and stores them in memory. For example, when detection by the surface thermometer 120 at all detection positions of each temperature sensor 77 for one reference temperature is completed, the surface temperature acquisition unit 83 acquires calibration information (surface temperatures at each detection position, time information) from the data logger 130.

[0064] Meanwhile, the temperature measurement value acquisition unit 84 acquires the temperatures (measured values) measured by each temperature sensor 77 and stores the measured values ​​in memory in association with the position information, time information, etc. of each temperature sensor 77. In particular, by acquiring the operating state of the movement control unit 82, the temperature measurement value acquisition unit 84 measures the temperature of a predetermined temperature sensor 77 in accordance with the timing at which the surface thermometer 120 detects the surface temperature at the detection position. This allows the measurement value of the predetermined temperature sensor 77 stored in memory and the surface temperature of the surface thermometer 120 to be values ​​detected at the same timing.

[0065] The correction value calculation unit 85 calculates a correction value as the difference between the measurement value of a predetermined temperature sensor 77 acquired by the temperature measurement acquisition unit 84 and the surface temperature of the predetermined temperature sensor 77 acquired from the data logger 130. The correction value calculation unit 85 calculates this correction value for each temperature sensor 77 and stores it in memory as a correction value corresponding to each of the plurality of temperature sensors 77. This correction value is stored so as to be linked to the measurement value of each temperature sensor 77. In other words, the value obtained by adding the correction value linked to the measurement value of each temperature sensor 77 becomes the calibration value of the temperature sensor 77 at the predetermined reference temperature.

[0066] When the correction value calculation unit 85 calculates the correction value for each of the plurality of reference temperatures, the calibration curve calculation unit 86 calculates a calibration curve for each of the plurality of temperature sensors 77 based on the measurement values ​​and correction values ​​stored in memory. The calibration curve calculation unit 86 also calculates this calibration curve for each of the plurality of temperature sensors 77, and stores the calculated calibration curve for each of the plurality of temperature sensors 77 in memory.

[0067] For example, the calibration curve for each temperature sensor 77 is calculated using a linear function with an appropriate slope and intercept based on multiple calibration values. Preferably, the calibration curve is calculated using two functions: a linear function from -55°C to 25°C, and a linear function from 25°C to 150°C. This allows the prober control unit 80 to have a highly accurate calibration curve for each of the multiple temperature sensors 77, making it possible to accurately measure the temperature distribution on the mounting surface 751 when the inspection device 1 inspects the wafer W. Note that the calibration curve for each temperature sensor 77 may be calculated using another function, such as a quadratic function, as long as it is calculated according to the characteristics of the sensor.

[0068] Furthermore, the confirmation unit 87 redetects the surface temperature of each temperature sensor 77 using the surface thermometer 120, sets the detected surface temperature as a check temperature, and confirms the calibration result by comparing the check temperature with the calibration value obtained by the correction value calculation unit 85. The operation of each component by the confirmation unit 87 is basically the same as the operation of each component during calibration, and details thereof will be described later.

[0069] When the inspection device 1 is operated after the temperature sensors 77 have been calibrated, the prober control unit 80 obtains the measurement value of each temperature sensor 77 based on the calibration curve set for each of the temperature sensors 77. This enables the prober control unit 80 to more accurately control the temperature adjustment mechanism 73, and to appropriately adjust the temperature of the mounting surface 751.

[0070] The temperature calibration system 100 according to this embodiment is configured as described above, and its operation (temperature calibration method) will be described below.

[0071] When the inspection device 1 is initially installed in a factory or during maintenance, an operator performs a temperature calibration method for calibrating the plurality of temperature sensors 77 of the prober 50. In performing the temperature calibration method, the operator first attaches the jig 110 to the frame structure 51 of the prober 50. This positions the surface thermometer 120 of the jig 110 in a position that allows it to face the mounting surface 751 of the chuck 70.

[0072] After attaching the jig 110, the worker performs the temperature calibration method by operating the control unit 9 (user interface, not shown) of the inspection device 1. As a result, the prober control unit 80, which has received a command to perform the temperature calibration method from the control unit 9, starts processing of the temperature calibration method.

[0073] Fig. 11 is a first flowchart showing the process flow of the temperature calibration method, and Fig. 12 is a second flowchart showing the process flow of the temperature calibration method. As shown in Figs. 11 and 12, in the temperature calibration method, the prober control unit 80 sequentially performs a temperature stabilization step, a calibration process step, and a confirmation step. Furthermore, the prober control unit 80 repeats the process flows of Figs. 11 and 12 for each of the three reference temperatures (-55°C, 25°C, and 150°C) to ultimately obtain a calibration curve for each temperature sensor 77.

[0074] Specifically, when the temperature calibration method is started, the prober control unit 80 first controls the temperature adjustment mechanism 73 by the temperature adjustment control unit 81 as a temperature stabilization step to adjust the temperature of the chuck 70 to a reference temperature in this processing flow (step S1). For example, the prober control unit 80 sets one of the multiple reference temperatures as the target temperature to be adjusted by the temperature adjustment mechanism 73.

[0075] Thereafter, the prober control unit 80 measures the temperature using a predetermined temperature sensor 77 for a predetermined stabilization period, and ensures that the difference between the maximum and minimum measured values ​​during the stabilization period is within the allowable temperature range (step S2). The stabilization period can be, for example, 5 to 10 minutes. The predetermined temperature sensor 77 that monitors the temperature is preferably a temperature sensor 77 in a stable region SA where the temperature is likely to stabilize. In this embodiment, the measured value of the temperature sensor 77 with channel number 1 in FIG. 6(a) is used. The allowable temperature range can be, for example, within ±0.5°C. As a result, when the temperature stabilization process is completed, the temperature of the mounting surface 751 is stabilized.

[0076] In the calibration process step after the temperature stabilization step, the prober control unit 80 controls the temperature adjustment mechanism 73 to maintain the reference temperature (step S3). Then, the prober control unit 80 controls the movement control unit 82 to control the movement unit 56, for example, in the numerical order of the temperature sensors 77 shown in Fig. 6(a), to bring the surface thermometer 120 into contact with a detection position on the mounting surface 751 that overlaps a predetermined temperature sensor 77 (step S4).

[0077] In controlling the moving unit 56, the prober control unit 80 first moves the chuck 70 in the horizontal direction (X and Y axis directions) so that the detection position of a predetermined temperature sensor 77 faces the detector 124 of the surface thermometer 120. Next, the prober control unit 80 raises the chuck 70 upward (positive Z-axis direction) to bring the detector 124 of the surface thermometer 120 into contact with the mounting surface 751. At this time, even after the lower end surface of the contact body 123 of the surface thermometer 120 comes into contact with the mounting surface 751, the prober control unit 80 continues to raise the chuck 70, displacing the surface thermometer 120 upward relative to the fixed block 113. As a result, the detector 124 of the surface thermometer 120 is deformed so as to come into contact with a predetermined area of ​​the mounting surface 751 (see FIG. 8(b)).

[0078] When the movement of the prober 50 is completed, the surface thermometer 120 detects the temperature at the detection position, and the data logger 130 receives the surface temperature from the surface thermometer 120 (step S5). At this time, the data logger 130 also acquires position information of the detection position (the installation position of the temperature sensor 77) on the mounting surface 751 facing the surface thermometer 120 from the prober control unit 80, and stores the position information of the detection position and the surface temperature in association with each other.

[0079] The prober control unit 80 also acquires the surface temperature of the surface thermometer 120 via the data logger 130 using the surface temperature acquisition unit 83, and monitors whether the difference between the maximum and minimum surface temperatures is within an allowable temperature range (e.g., ±0.5°C) over a predetermined period (step S6). The predetermined period for monitoring the surface temperature is not particularly limited, but may be set, for example, to several tens of seconds to several minutes. If the difference between the maximum and minimum values ​​exceeds the allowable temperature range (step S6: NO), this means that the temperature adjustment by the temperature adjustment mechanism 73 has become unstable. Therefore, the prober control unit 80, for example, temporarily suspends the calibration process and starts again from step S1.

[0080] On the other hand, if the difference between the maximum and minimum values ​​is within the allowable temperature range (step S6: YES), it means that the temperature adjustment by the temperature adjustment mechanism 73 is stable. Therefore, in step S7, the prober control unit 80 acquires the surface temperature of the surface thermometer 120 at the end of the predetermined period using the surface temperature acquisition unit 83, and acquires the measurement value of the predetermined temperature sensor 77 corresponding to the detection position using the temperature measurement acquisition unit 84.

[0081] Furthermore, the correction value calculation unit 85 of the prober control unit 80 calculates the difference (correction value) between the measurement value of the predetermined temperature sensor 77 and the surface temperature of the surface thermometer 120, and stores the difference in memory. At the reference temperature of this processing flow, the measurement value of the predetermined temperature sensor 77 becomes equal to the surface temperature of the surface thermometer 120 by adding the calculated correction value.

[0082] After step S7 is completed, the prober control unit 80 lowers the chuck 70 downward (in the negative direction of the Z axis) to separate the detector 124 of the surface thermometer 120 from the mounting surface 751. The prober control unit 80 then determines whether or not the surface thermometer 120 has performed detection at all of the detection positions of the temperature sensors 77 on the mounting surface 751 (step S8). If the detection of each temperature sensor 77 has not been completed (step S8: NO), the prober control unit 80 returns to step S4 and repeats the same process flow. On the other hand, if calibration values ​​(correction values) have been obtained for all of the detection positions of the temperature sensors 77, the calibration process is completed and the process proceeds to the confirmation process shown in FIG. 12.

[0083] In the confirmation step, the confirmation unit 87 controls the movement unit 56 of the prober 50 via the movement control unit 82 to bring the surface thermometer 120 into contact with the detection position of each temperature sensor 77 on the mounting surface 751 again (step S9). As a result, the surface thermometer 120 detects the temperature at the detection position as a check temperature (step S10).

[0084] Furthermore, the confirmation unit 87 continuously acquires the measurement value of the temperature sensor 77 at the detection position using the temperature measurement value acquisition unit 84, and monitors whether the difference between the maximum and minimum measurement values ​​is within the allowable temperature range (for example, ±0.5°C) over a predetermined period of time (step S11). The measurement value of this temperature sensor 77 reflects the calibration value (correction value) acquired in step S7. If the difference between the maximum and minimum measurement values ​​exceeds the allowable temperature range (step S6: NO), this means that the temperature adjustment by the temperature adjustment mechanism 73 has become unstable. For this reason, for example, the confirmation unit 87 temporarily suspends the confirmation process and starts again from step S9.

[0085] On the other hand, if the difference between the maximum and minimum values ​​is within the allowable temperature range (step S11: YES), the temperature adjustment by the temperature adjustment mechanism 73 is stable. Therefore, in step S12, the confirmation unit 87 acquires the surface temperature of the surface thermometer 120 at the end of the predetermined period using the surface temperature acquisition unit 83. Furthermore, the confirmation unit 87 compares the surface temperature at the detection position (check temperature) with the measurement value of the calibrated temperature sensor 77, and determines whether the difference between the check temperature and the calibrated measurement value is within the predetermined specifications (specs) (step S13). If the difference between the check temperature and the calibrated measurement value exceeds the specifications, the process proceeds to step S14, where an error is output via the user interface. The specifications are preferably set based on the specifications (error range) of the temperature sensor 77.

[0086] On the other hand, if the check temperature and the calibrated measurement value are within the specification range, the calibration result of that temperature sensor 77 is recognized as normal, and the process proceeds to step S15. Then, the confirmation unit 87 determines whether confirmation has been performed for all detection positions of each temperature sensor 77 (step S15). If confirmation of each temperature sensor 77 has not been completed (step S15: NO), the confirmation unit 87 returns to step S9 and repeats the same processing flow thereafter. On the other hand, if confirmation has been completed for all detection positions of each temperature sensor 77 (step S15: YES), the confirmation process ends.

[0087] Then, the calibration curve calculation unit 86 of the prober control unit 80 performs the above process flow (calibration of the measurement values ​​of each temperature sensor 77) for the three reference temperatures, and calculates the calibration curve for each temperature sensor 77 based on the calibration values ​​for the three points. This allows the prober control unit 80 to match the measurement values ​​of each temperature sensor 77 with the surface temperature detected by the surface thermometer 120, and as a result, calibrates them to comply with the national standard.

[0088] The temperature calibration system 100 and the temperature calibration method are not limited to the above-described embodiment and may be modified in various ways. For example, the temperature calibration system 100 may include a position detector 140 that detects the position of the surface thermometer 120 or the position of the chuck 70, as shown by the dotted lines in FIG. 7( a). Examples of the position detector 140 include a camera that captures an image of the area around the surface thermometer 120, and a displacement meter (such as a laser displacement meter) that measures the distance to the surface thermometer 120 or the distance to the chuck 70. The position detector 140 enables the prober control unit 80 to accurately recognize the relative position between the mounting surface 751 of the chuck 70 and the surface thermometer 120. Therefore, by feeding back the relative position, the prober control unit 80 can more accurately move the prober 50 relative to the surface thermometer 120, thereby more reliably bringing the surface thermometer 120 into contact with the detection position of each temperature sensor 77.

[0089] Furthermore, for example, the temperature calibration system 100 is not limited to a configuration in which the moving part 56 (mounting surface 751) of the prober 50 moves the mounting surface 751 relative to the surface thermometer 120, but may also be configured to move the surface thermometer 120 relative to the mounting surface 751.

[0090] Second Embodiment 13 is a schematic plan view of a chuck 70 of a temperature calibration system 100 according to the second embodiment. As shown in FIG. 13, the temperature calibration system 100 according to the second embodiment uses one of the temperature sensors 77 as a reference sensor 77A for detecting failures of the other temperature sensors 77. It is preferable that the reference sensor 77A is a temperature sensor 77 in a stable region SA where the temperature is likely to stabilize, among the temperature sensors 77. For example, it is preferable to use the temperature sensor 77 with channel number 1 or 17 in FIG. 13. In this embodiment, the temperature sensor 77 with channel number 17 is used as the reference sensor 77A.

[0091] The temperature sensor 77 applied to the reference sensor 77A is preferably located in a position where the temperature is likely to stabilize, and has specifications such as heat resistance and measurement accuracy (tolerance range) superior to those of the other temperature sensors 77. For example, the reference sensor 77A may be a platinum resistance thermometer, which has a higher precision resistance element than the resistance thermometers (thermistors, for example) of the other temperature sensors 77.

[0092] Furthermore, it is preferable that the reference sensor 77A is housed inside a protective tube 79 and installed on the back surface of the top plate 75, thereby protecting the sensor from the atmosphere around the prober 50. The protective tube 79 is made of stainless steel (SUS304) or the like. The reference sensor 77A installed inside the protective tube 79 is more resistant to foreign matter than the top plate 75 around the protective tube 79. In other words, of all the temperature sensors 77, the reference sensor 77A is less likely to malfunction.

[0093] This reference sensor 77A can also perform temperature measurements that conform to national standards (are traceable to national standards) by performing temperature calibration using the surface thermometer 120 when installing or maintaining the inspection device 1. Therefore, the reference sensor 77A can accurately measure the temperature of the mounting surface 751 at the detection position, and is highly reliable and easy to reference compared to other temperature sensors 77.

[0094] The prober control unit 80A according to the second embodiment performs a process of detecting failures in the other multiple (16) temperature sensors 77 using the reference sensor 77A during operation of the inspection device 1. That is, the inspection device 1 periodically or as needed performs a sensor failure detection method that determines whether the multiple temperature sensors 77 are normal or abnormal. The sensor failure detection method is performed using the reference sensor 77A calibrated by the temperature calibration method, and in that sense is a process related to the temperature calibration method of the present disclosure. This sensor failure detection method will be described in detail below.

[0095] FIG. 14 is a flowchart showing the processing flow of the sensor failure detection method. As shown in FIG. 14, during operation of the inspection apparatus 1, the prober control unit 80 first determines whether to perform the sensor failure detection method (step S21). For example, the prober control unit 80 sets a failure detection flag when the elapsed time since the previous time the temperature calibration method or the sensor failure detection method was performed, the cumulative period during which the wafer W is being inspected, or the difference in the measurement values ​​of each temperature sensor 77 is greater than or equal to a predetermined value. The prober control unit 80 then references the failure detection flag when the inspection apparatus 1 is started, before the start of inspection of the wafer W, or while waiting for inspection of the wafer W. If the failure detection flag is set to 1, the prober control unit 80 performs the sensor failure detection method. If the failure detection flag is set to 0, the prober control unit 80 determines not to perform the sensor failure detection method (step S21: NO) and proceeds to inspection of the wafer W.

[0096] When the sensor failure detection method is to be performed (step S21: YES), the prober control unit 80 operates the temperature adjustment mechanism 73 to change the temperature of the mounting surface 751 of the chuck 70 to an appropriate target temperature (step S22). The target temperature is not particularly limited, but examples include a temperature set during inspection of the wafer W (e.g., 85°C) and a reference temperature targeted in a temperature calibration method (e.g., -55°C, 25°C, 155°C). The prober control unit 80 may perform the sensor failure detection method at only one target temperature, or may perform the sensor failure detection method for each of multiple target temperatures. Performing the sensor failure detection method at one target temperature can shorten the operation time, while performing the sensor failure detection method at multiple target temperatures can increase the accuracy of failure detection.

[0097] In the temperature control of the mounting surface 751 by the temperature adjustment mechanism 73, the prober control unit 80 measures the temperature of the mounting surface 751 using the reference sensor 77A and stores the measurement result in memory (step S23). Furthermore, the prober control unit 80 makes the difference between the maximum and minimum values ​​of the measured values ​​in a predetermined stabilization period fall within the allowable temperature range (step S24).

[0098] Thereafter, the prober control unit 80 measures the temperature of the mounting surface 751 at each detection position for all temperature sensors 77 other than the reference sensor 77A, and stores each measurement result in memory (step S25). At this time, the prober control unit 80 may perform temperature measurement by each temperature sensor 77 for a predetermined period, monitor whether the difference between the maximum and minimum values ​​of each measurement value is within an allowable temperature range (for example, ±0.5°C), and extract the last measurement value for the predetermined period.

[0099] After measuring the temperatures of the temperature sensors 77, the prober control unit 80 calculates a difference for fault detection between the measured value of each temperature sensor 77 other than the reference sensor 77A and the reference temperature value (measured value) of the reference sensor 77A (step S26). This difference for fault detection is preferably calculated as an absolute value.

[0100] Next, the prober control unit 80 compares each failure detection difference of each temperature sensor 77 other than the reference sensor 77A with a pre-stored failure threshold and determines whether each failure detection difference is equal to or less than the failure threshold (step S27). The failure threshold is not particularly limited as long as it is an appropriate value that is considered to indicate a sensor failure, and may be set to, for example, 1°C. If the failure detection difference is equal to or less than the failure threshold, the temperature sensor 77 can be considered to have no abnormality, such as a failure. If all temperature sensors 77 other than the reference sensor 77A are normal (step S27: YES), the prober control unit 80 proceeds to step S28 and performs an end process for the sensor failure detection method. In the end process, the prober control unit 80 resets the failure detection flag to 0 and identifies the next operation of the inspection apparatus 1 (e.g., start of inspection of the wafer W), and transitions to another control by resetting the target temperature of the temperature adjustment mechanism 73, for example.

[0101] On the other hand, if the failure detection difference exceeds the failure threshold (step S27: NO), it can be determined that an abnormality such as a failure has occurred in that temperature sensor 77. Therefore, if the prober control unit 80 determines that at least one of the temperature sensors 77 is abnormal, the process proceeds to step S29. In step S29, the prober control unit 80 notifies the user, via the user interface of the control unit 9, that an abnormality has occurred in the temperature sensor 77 of the prober 50. This allows the user to easily and quickly recognize the abnormality in the temperature sensor 77.

[0102] Third Embodiment 15 is a schematic explanatory diagram showing an inspection apparatus 1A equipped with a temperature calibration system 100 according to the third embodiment. As shown in FIG. 15, the inspection apparatus 1A may be configured to automatically calibrate each temperature sensor 77 of the chuck 70 as needed (or at predetermined intervals) by providing the temperature calibration system 100 inside the housing 2. For example, the inspection apparatus 1A includes a surface thermometer 120 of the temperature calibration system 100 on the side of the row of inspection chambers 16.

[0103] When starting the temperature calibration method, the inspection apparatus 1A moves the prober 50 along the X and Y axes to position the mounting surface 751 of the chuck 70 facing the surface thermometer 120. After positioning the prober 50, the prober control unit 80 performs the temperature calibration method in accordance with the process flow of FIG. 11, thereby enabling calibration of each temperature sensor 77 during the initial installation of the inspection apparatus 1 and during operation after maintenance. Note that it is advisable to ensure traceability of the surface thermometer 120 by calibrating it against a standard 200 conforming to a national standard during maintenance of the inspection apparatus 1, etc.

[0104] The technical ideas and effects of the present disclosure explained in the above embodiments will be described below.

[0105] A first aspect of the present disclosure is a temperature calibration system 100 having an inspection apparatus 1 that adjusts the temperature of an object to be inspected (wafer) placed on a mounting portion (chuck 70) to inspect the object to be inspected, and a surface thermometer 120, and that calibrates multiple temperature sensors 77 provided on the mounting portion, wherein the inspection apparatus 1 has a moving unit 56 that can move the mounting portion in the X-axis, Y-axis, and Z-axis directions, and a control unit (prober control unit 80) that performs calibration processing on the measured values ​​of the multiple temperature sensors 77, wherein the surface thermometer 120 contacts a mounting surface 751 of the mounting portion to detect the surface temperature of the mounting surface 751, and the control unit controls the moving unit 56 to bring the surface thermometer 120 into contact with a detection position on the mounting surface 751 of the mounting portion, the surface thermometer 120 detects the surface temperature at the detection position, and calibrates the measured value of the temperature sensor 77 corresponding to the detection position based on the surface temperature at the detection position.

[0106] As described above, the temperature calibration system 100 calibrates multiple temperature sensors 77 using one surface thermometer 120, thereby avoiding variations in calibration due to equipment and enabling accurate calibration of the measurement values ​​of each temperature sensor 77. Furthermore, the temperature calibration system 100 moves the mounting unit (chuck 70) in conjunction with the moving unit 56 to bring the surface thermometer 120 into contact with the detection position, thereby suppressing errors in the detection position of the temperature sensor 77 and enabling accurate determination of the surface temperature.

[0107] Furthermore, surface thermometer 120 includes contact member 123 that contacts mounting surface 751, and detector 124 that protrudes outward from contact member 123 and is elastically deformable when it contacts mounting surface 751. This allows surface thermometer 120 to make the shape of detector 124 elastically deformed uniform when mounting surface 751 is in contact with contact member 123, thereby improving the detection accuracy of the surface temperature for each temperature sensor 77.

[0108] Furthermore, the contact body 123 is formed in a ring shape that accommodates a portion of the detector 124 inside, and the detector 124 is formed in a plate shape that is thinner than the wall thickness of the contact body 123. Such a thin, plate-shaped detector 124 has a small heat capacity, resulting in fast thermal response and enabling efficient calibration of the multiple temperature sensors 77. Furthermore, by bringing the surface of the ring-shaped contact body 123 into contact with the mounting surface 751, the shape of the detector 124 can be more reliably matched.

[0109] Furthermore, the surface thermometer 120 is attached to a jig 110 fixed to a plurality of supports 54 provided around the mounting portion, and is positioned above the mounting surface 751. This makes it possible for the temperature calibration system 100 to calibrate each temperature sensor 77 by directly applying the moving unit 56 of the inspection device 1 that moves the mounting portion, thereby simplifying the system.

[0110] Furthermore, the jig 110 has a relief structure 115 that holds the surface thermometer 120 so that it can be displaced in the Z-axis direction, and the relief structure 115 relieves the pressing force received from the mounting surface 751 when the surface thermometer 120 comes into contact with the mounting surface 751. This allows the temperature calibration system 100 to obtain a surface temperature with better reproducibility because the weight of the surface thermometer 120 or the pressing force on the detector 124 acts evenly.

[0111] The control unit (prober control unit 80) also has a storage device (data logger 130) that stores the temperature sensor 77 at the detection position in association with the surface temperature at the detection position detected by the surface thermometer 120. This allows the temperature calibration system 100 to easily accumulate the surface temperature detected by the surface thermometer 120 and the position of the temperature sensor 77.

[0112] Furthermore, in the calibration process, the control unit (prober control unit 80) calibrates the measurement values ​​for each of a plurality of target temperatures using the temperature adjustment mechanism 73, and obtains calibration curves for each of the plurality of temperature sensors 77 based on the calibration results for each of the plurality of target temperatures. This enables the control unit to accurately grasp the temperature distribution on the mounting surface 751 of the object to be inspected (wafer W) from the measurement values ​​of each temperature sensor 77.

[0113] Furthermore, at least one of the plurality of temperature sensors 77 is provided in a stable area SA where the temperature stabilizes on the mounting surface 751, and the control unit (prober control unit 80) controls the temperature of the mounting part (chuck 70) in the calibration process based on the measurement value of the temperature sensor 77 in the stable area SA. This allows the temperature calibration system 100 to perform the calibration process for each temperature sensor 77 while the temperature of the mounting part is reliably stabilized.

[0114] Furthermore, the detection value of the surface thermometer 120 is calibrated to a value conforming to the national standard, which allows the temperature calibration system 100 to trace the measurement values ​​of the multiple temperature sensors 77 calibrated using the surface temperatures detected by the surface thermometer 120 to the national standard.

[0115] The plurality of temperature sensors 77 also includes at least one reference sensor 77A, and the control unit compares a reference value measured by the reference sensor 77A with measurements measured by the plurality of temperature sensors 77 other than the reference sensor 77A, and if the measurement value deviates from the reference value by a predetermined amount or more, determines that the temperature sensor 77 whose measurement value deviates is abnormal. This allows the temperature calibration system 100 to easily and accurately determine whether each temperature sensor 77 is normal or abnormal, periodically or as needed.

[0116] Furthermore, the reference sensor 77A is provided in a stable area SA where the temperature stabilizes on the placement surface 751. This allows the reference sensor 77A to measure the temperature of the placement surface 751 stably.

[0117] Furthermore, a second aspect of the present disclosure is an inspection apparatus 1 for inspecting an object to be inspected, which comprises a mounting section (chuck 70) on which the object to be inspected (wafer W) is mounted and which adjusts the temperature of the object to be inspected, a plurality of temperature sensors 77 provided on the mounting section, a moving section 56 which can move the mounting section in the X-axis direction, the Y-axis direction, and the Z-axis direction, and a control section (prober control section 80) which performs a calibration process on the measured values ​​of the plurality of temperature sensors 77, and which is equipped with a surface thermometer 120 which contacts a mounting surface 751 of the mounting section to detect the surface temperature of the mounting surface 751, and the control section controls the moving section 56 to bring the surface thermometer 120 into contact with a detection position on the mounting surface 751 of the mounting section, detects the surface temperature at the detection position using the surface thermometer 120, and calibrates the measured value of the temperature sensor 77 corresponding to the detection position based on the surface temperature.

[0118] Furthermore, a third aspect of the present disclosure is a temperature calibration method having an inspection apparatus 1 that adjusts the temperature of an object to be inspected (wafer W) placed on a mounting portion (chuck 70) to inspect the object to be inspected, and a surface thermometer 120, and that calibrates multiple temperature sensors 77 provided on the mounting portion, the method comprising: a first step of adjusting the temperature of the mounting portion; a second step of moving the mounting portion using a moving portion 56 that is movable in the X-axis, Y-axis, and Z-axis directions to bring the surface thermometer 120 into contact with a detection position on the mounting surface 751 of the mounting portion; and a third step of detecting the surface temperature at the detection position on the mounting surface 751 using the surface thermometer 120 and calibrating the measurement value of the temperature sensor 77 corresponding to the detection position based on the surface temperature, and while the first step is being performed, the first and second steps are repeated for all of the multiple temperature sensors 77.

[0119] In the second and third embodiments described above, the plurality of temperature sensors 77 can also be calibrated with high precision.

[0120] The temperature calibration system 100, the inspection apparatus 1, and the temperature calibration method according to the presently disclosed embodiments are illustrative and not restrictive in all respects. Various modifications and improvements to the embodiments are possible without departing from the spirit and scope of the appended claims. The features described in the above-described embodiments may be configured differently and combined within a consistent range. For example, the object to be inspected by the inspection apparatus 1 is not limited to a substrate (wafer W) but may be various electrical and electronic devices requiring electrical testing. The inspection apparatus 1 is not limited to having multiple inspection units 40 (testers 41) but may also have a single inspection unit 40. Even in this case, the prober 50 includes a temperature adjustment mechanism 73 and multiple temperature sensors 77, allowing it to adjust the temperature of the chuck 70 and move the chuck 70 carrying the wafer W. The above-described temperature calibration method allows for satisfactory calibration of the multiple temperature sensors 77.

[0121] The temperature calibration system 100 of the present disclosure is not limited to one that calibrates the plurality of temperature sensors 77 provided on the chuck 70 of the inspection apparatus 1. For example, the temperature calibration system 100 can calibrate the plurality of temperature sensors 77 in a configuration in which the plurality of temperature sensors 77 are provided on a mounting part (mounting table, chuck, etc.) installed in a processing vessel of a substrate processing apparatus. [Explanation of symbols]

[0122] 1. Inspection equipment 56 Mobile Unit 70 Chuck 751 Placement surface 77 Temperature Sensor 80 Prober control unit 100 Temperature Calibration System 120 Surface thermometer W wafer

Claims

1. A temperature calibration system comprising: an inspection device that adjusts the temperature of an object to be inspected placed on a placement section and inspects the object; and a surface thermometer, the temperature calibration system calibrating a plurality of temperature sensors provided on the placement section, The inspection device includes: a moving unit that can move the placement unit in X-axis directions, Y-axis directions, and Z-axis directions; a control unit that performs a calibration process on the measurement values ​​of the plurality of temperature sensors, the surface thermometer contacts the mounting surface of the mounting unit to detect the surface temperature of the mounting surface; the control unit controls the moving unit to bring the surface thermometer into contact with a detection position on the placement surface of the placement unit, detects a surface temperature at the detection position with the surface thermometer, and calibrates a measurement value of the temperature sensor corresponding to the detection position based on the surface temperature. Temperature calibration system.

2. The surface thermometer is a contact body that contacts the mounting surface; a detector that protrudes outward from the contact body and is elastically deformable when it comes into contact with the placement surface, The temperature calibration system of claim 1 .

3. the contact body is formed in an annular shape to accommodate a part of the detector therein, The detector is formed in a plate shape having a thickness thinner than that of the contact body. The temperature calibration system of claim 2 .

4. the surface thermometer is attached to a jig fixed to a plurality of supports provided around the mounting portion, and is disposed above the mounting surface; 4. The temperature calibration system according to claim 1.

5. the jig has a relief structure that holds the surface thermometer so that it can be displaced in the Z-axis direction, the relief structure relieves a pressing force received from the placement surface when the surface thermometer comes into contact with the placement surface; 5. The temperature calibration system of claim 4.

6. The control unit has a storage device that stores the temperature sensor at the detection position and the surface temperature at the detection position detected by the surface thermometer in association with each other.

6. A temperature calibration system according to any one of claims 1 to 5.

7. In the calibration process, the control unit calibrates the measurement values ​​for each of a plurality of target temperatures using a temperature adjustment mechanism, and obtains a calibration curve for each of the plurality of temperature sensors based on the calibration results for each of the plurality of target temperatures.

7. A temperature calibration system according to any one of claims 1 to 6.

8. At least one of the plurality of temperature sensors is provided in a stable region where the temperature of the mounting surface is stabilized, the control unit controls the temperature of the mounting unit based on the measurement value of the temperature sensor in the stable region during the calibration process.

8. A temperature calibration system according to any one of claims 1 to 7.

9. The detected value of the surface thermometer is calibrated to a value conforming to the national standard.

9. A temperature calibration system according to any one of claims 1 to 8.

10. the plurality of temperature sensors includes at least one reference sensor; the control unit compares a reference value measured by the reference sensor with measurement values ​​measured by the plurality of temperature sensors other than the reference sensor, and when the measurement values ​​deviate from the reference value by a predetermined amount or more, determines that the temperature sensor whose measurement values ​​deviate is abnormal.

10. A temperature calibration system according to any one of claims 1 to 9.

11. the reference sensor is provided in a stable region of the mounting surface where temperature is stabilized; The temperature calibration system of claim 10.

12. An inspection device for inspecting an object to be inspected, a mounting unit for mounting the object to be inspected and adjusting the temperature of the object to be inspected; a plurality of temperature sensors provided on the mounting portion; a moving unit that can move the placement unit in X-axis directions, Y-axis directions, and Z-axis directions; a control unit that performs a calibration process on the measurement values ​​of the plurality of temperature sensors, a surface thermometer that contacts the mounting surface of the mounting unit to detect the surface temperature of the mounting surface, the control unit controls the moving unit to bring the surface thermometer into contact with a detection position on the placement surface of the placement unit, detects a surface temperature at the detection position with the surface thermometer, and calibrates a measurement value of the temperature sensor corresponding to the detection position based on the surface temperature. Inspection equipment.

13. 1. A temperature calibration method for calibrating a plurality of temperature sensors provided on a mounting section, the method comprising: an inspection device for inspecting an object to be inspected by adjusting the temperature of the object to be inspected placed on a mounting section; and a surface thermometer; a first step of adjusting the temperature of the mounting portion; a second step of moving the placement unit using a moving unit that is movable in the X-axis direction, the Y-axis direction, and the Z-axis direction to bring the surface thermometer into contact with a detection position on the placement surface of the placement unit; a third step of detecting a surface temperature of the detection position on the mounting surface by the surface thermometer and calibrating a measurement value of the temperature sensor corresponding to the detection position based on the detected surface temperature; repeating the first step and the second step for all of the plurality of temperature sensors while the first step is being performed; Temperature correction method.

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