Temperature control device, temperature control method, program, and prober

Abstract

To provide a temperature control device, a temperature control method, a program, and a prober that can execute automatic adjustment of a chuck temperature control parameter.SOLUTION: A temperature control device (21) comprises: a chuck temperature acquisition unit (100) that acquires a chuck temperature; a feature quantity derivation unit that derives the feature quantity of a change in the chuck temperature; a classification unit (102) that refers to the correspondence between the feature of the change in the chuck temperature and a temperature change pattern, and when the chuck temperature is input, outputs the temperature change pattern; and a temperature control parameter setting unit (104) that derives a temperature control parameter corresponding to the temperature change pattern output from the classification unit, and sets the temperature control parameter. The temperature control device applies the temperature control parameter to control the operation of a chuck temperature adjustment unit that adjusts the chuck temperature.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a temperature control device, a temperature control method, a program, and a prober that are applied to inspection of electrical characteristics of semiconductor chips formed on a wafer. [Background technology]

[0002] A plurality of semiconductor chips each having the same electrical element circuit are formed on the surface of a wafer, and the electrical characteristics of each semiconductor chip are inspected using a wafer test system equipped with a prober and a tester.

[0003] The prober, while holding a wafer on the wafer chuck, moves a probe card equipped with probe needles relative to the wafer chuck to electrically connect the probe needles to the electrode pads of the semiconductor chip. The tester supplies various test signals to the semiconductor chip from terminals electrically connected to the probe needles, receives signals output from the semiconductor chip, and analyzes the received signals to test whether the semiconductor chip operates normally.

[0004] Since semiconductor chips are used in a wide range of applications and temperatures, the semiconductor chips are inspected at temperatures corresponding to the environments in which the semiconductor chips are expected to be used, such as room temperature, high temperature, and low temperature. Note that room temperature here may include the concept of normal temperature. Low temperature means a temperature environment that is relatively low compared to room temperature. Similarly, high temperature means a temperature environment that is relatively high compared to room temperature.

[0005] The wafer chuck of the prober is equipped with a temperature adjustment device including, for example, a heater mechanism, a chiller mechanism, and a heat pump mechanism, and the wafer held on the wafer chuck is heated or cooled using the temperature adjustment device.

[0006] Patent Document 1 describes an IC test handler that is equipped with a temperature sensor for the wafer and directly measures the wafer temperature, which is a disturbance factor in chuck temperature control. The device described in the document uses a non-contact thermometer to measure the surface temperature of the IC package that houses the IC.

[0007] Patent Document 2 describes an inspection device that measures the temperature of a wafer using an infrared sensor provided on a probe card. When measuring an electronic device, the device described in this document measures the temperature of the electronic device using an infrared sensor provided on the probe card.

[0008] Patent Document 3 describes an inspection device that estimates the amount of heat generated by a wafer based on the power output from a tester and performs temperature correction of a chuck based on the amount of heat generated by the wafer. The device described in this document receives power supplied from a power supply unit to an electronic device to be inspected, estimates the amount of heat generated by the electronic device based on the power supplied to the electronic device, estimates the temperature difference between the electronic device and the chuck from the amount of heat generated by the electronic device, and controls the temperature of the chuck using the estimated temperature difference.

[0009] The devices described in Patent Documents 1 to 3 measure or estimate the temperature of the wafer, i.e., disturbance, and use the measurement or estimation results to perform temperature control, thereby improving the performance of temperature control in wafer inspection. Note that the IC described in Patent Document 1 and the electronic devices described in Patent Documents 2 and 3 correspond to the semiconductor chips formed on the wafer described above. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2018-80919 A [Patent Document 2] Patent Publication No. 2021-128965 [Patent Document 3] JP 2022-90538 A Summary of the Invention [Problem to be solved by the invention]

[0011] However, in the embodiment of Patent Document 1 in which a temperature sensor is provided on the wafer and the embodiment of Patent Document 2 in which a temperature sensor is provided on the probe card, a temperature sensor that is provided outside the prober system is required. If a temperature sensor cannot be provided on the wafer or the probe card due to design issues or the like, there are cases in which accurate temperature control cannot be performed.

[0012] Furthermore, in the aspect of estimating the amount of heat generated by a wafer based on the power output from a tester described in Patent Document 3, the power output from the tester depends on the specifications of the tester, making it difficult to perform general-purpose measurement on multiple wafers of different types.

[0013] That is, to realize versatile measurements for a plurality of different types of wafers, it is necessary to perform temperature control using information such as coefficients that can be directly acquired by the prober, such as the temperature of the chuck.

[0014] In addition, the amount of heat generated by the wafer and the heat generation pattern of the wafer differ due to differences in the type of wafer, such as differences in the type of semiconductor chip formed on the wafer, etc. In this case, in wafer temperature control to which existing temperature control parameters are applied, when a temperature change occurs due to disturbances such as differences in the type of wafer, there is a concern that a delay in the time until the temperature converges to a target temperature and hunting of the controlled variable may occur.

[0015] The delay in the time it takes to converge to the target temperature reduces the measurement throughput. Hunting of the controlled variable makes the temperature control unstable, and there is concern that the accuracy of the temperature control will decrease. The decrease in the accuracy of the temperature control will cause inappropriate wafer inspection.

[0016] If there is a time delay until the temperature converges to the target temperature, it is necessary to adjust the temperature control parameters for each wafer to be measured. Meanwhile, for example, the temperature control of the chuck involves integrated heating and cooling control, and it is not easy to determine the temperature control parameters. In addition, the wafer is owned by the user who uses the inspection device, and it is difficult to adjust the temperature control parameters using the wafer to be measured before the inspection, so the temperature control parameters are adjusted manually during the measurement. This causes problems such as the adjustment of the temperature control parameters depending on the individual and reduced productivity.

[0017] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a temperature control device, a temperature control method, a program, and a prober that are capable of automatically adjusting the control parameters of the chuck temperature. [Means for solving the problem]

[0018] A temperature control device according to a first aspect of the present disclosure includes a chuck temperature acquisition unit that acquires a chuck temperature representing the temperature of a wafer chuck that holds a wafer on which a plurality of semiconductor chips are formed; a classification unit that applies a learned model that learns the correspondence between the characteristics of changes in the chuck temperature and a specified number of temperature change patterns into which changes in the chuck temperature are classified, and that outputs a temperature change pattern corresponding to the input change in the chuck temperature when the chuck temperature is input; and a temperature control parameter setting unit that derives temperature control parameters corresponding to the temperature change pattern output from the classification unit when the chuck temperature is input to the classification unit, and sets the temperature control parameters, and is a temperature control device that controls the operation of a chuck temperature adjustment unit that adjusts the chuck temperature by applying the temperature control parameters set using the temperature control parameter setting unit.

[0019] According to the temperature control device of the present disclosure, a classification unit to which a learned model that has learned the correspondence between the characteristics of changes in chuck temperature and the pattern of changes in chuck temperature is applied is used, and when an acquired chuck temperature is input to the classification unit, the temperature control parameters output from the classification unit are applied to a temperature adjustment unit that adjusts the chuck temperature. This makes it possible to automatically adjust the temperature control parameters applied to the chuck temperature adjustment unit that adjusts the chuck temperature based on the chuck temperature.

[0020] The temperature control parameters may comprise heating control parameters applied in heating the wafer chuck and cooling control parameters applied in cooling the wafer chuck.

[0021] The temperature control parameters may include multiple components.

[0022] The temperature control device according to a second aspect may be the temperature control device according to the first aspect, further comprising a chuck temperature change derivation section that derives a change in the chuck temperature from a plurality of chuck temperatures acquired at different times.

[0023] According to this aspect, temperature control parameters can be derived based on the characteristics of the change in chuck temperature.

[0024] A temperature control device according to a third aspect is a temperature control device according to the first aspect, in which the trained model learns the correspondence between features representing characteristics of changes in chuck temperature and temperature change patterns into which the changes in chuck temperature are classified, and the classification unit acquires the features as characteristics of the changes in chuck temperature and outputs a temperature change pattern corresponding to the features.

[0025] According to this aspect, the change in chuck temperature can be classified based on a feature amount that quantifies the characteristic of the change in chuck temperature.

[0026] A temperature control device according to a fourth aspect is a temperature control device according to any one of the first to third aspects, wherein the temperature control parameter setting unit derives a temperature control parameter using an adjustment coefficient corresponding to a temperature change pattern.

[0027] In such an embodiment, a PID control parameter may be applied as the temperature control parameter.

[0028] A temperature control device according to a fifth aspect is a temperature control device according to any one of the first to fourth aspects, and includes a wafer information acquisition unit that acquires wafer information including the type of wafer to be measured, and a plurality of trained models that are trained and generated for each type of wafer, and the classification unit may select one trained model from the plurality of trained models depending on the type of wafer included in the wafer information acquired using the wafer information acquisition unit.

[0029] According to this aspect, the change in chuck temperature can be classified according to the type of wafer.

[0030] A temperature control method according to a sixth aspect of the present disclosure is a temperature control method in which a computer executes the following steps: acquiring a chuck temperature representing the temperature of a wafer chuck that holds a wafer on which a plurality of semiconductor chips are formed; outputting a temperature change pattern corresponding to the input chuck temperature change when the chuck temperature is input using a classification unit to which a trained model is applied that has learned the correspondence between the characteristics of the chuck temperature change and a specified number of temperature change patterns into which the chuck temperature change is classified; deriving temperature control parameters corresponding to the temperature change pattern output from the classification unit when the chuck temperature is input to the classification unit, and setting the temperature control parameters; and applying the temperature control parameters to control the operation of a chuck temperature adjustment unit that adjusts the chuck temperature.

[0031] According to the temperature control method of the present disclosure, it is possible to obtain the same effects as those of the temperature control device of the present disclosure.

[0032] In the temperature control method according to the present disclosure, the same items as those specified in any one of the second to fifth aspects can be appropriately combined. In this case, the components performing the processes or functions specified in the temperature control device can be understood as the components of the temperature control method performing the corresponding processes or functions.

[0033] A program according to a seventh aspect of the present disclosure is a program that causes a computer to realize the following functions: acquiring a chuck temperature representing the temperature of a wafer chuck that holds a wafer on which a plurality of semiconductor chips are formed; outputting a temperature change pattern corresponding to a change in chuck temperature inputted when the chuck temperature is inputted using a classification unit to which a trained model that has learned the correspondence between the characteristics of changes in chuck temperature and a specified number of temperature change patterns into which changes in chuck temperature are classified; deriving a temperature control parameter corresponding to the temperature change pattern outputted from the classification unit when the chuck temperature is inputted to the classification unit, and setting the temperature control parameter; and controlling the operation of a chuck temperature adjustment unit that adjusts the chuck temperature by applying the temperature control parameter.

[0034] According to the program of the present disclosure, it is possible to obtain the same effects as those of the temperature control device of the present disclosure.

[0035] In the program according to the present disclosure, the same items as those specified in any one of the second to fifth aspects can be appropriately combined. In this case, the components performing the processes or functions specified in the temperature control device can be understood as the components of the program performing the corresponding processes or functions.

[0036] A prober according to an eighth aspect of the present disclosure is a prober comprising: a wafer chuck that holds a wafer on which a plurality of semiconductor chips are formed; a probe card having probe needles; a relative movement unit that moves the wafer chuck relatively to the probe needles; a chuck temperature adjustment device that adjusts the temperature of the wafer chuck; and a temperature control device that applies temperature control parameters to control the operation of the chuck temperature adjustment device. The temperature control device comprises: a chuck temperature acquisition unit that acquires a chuck temperature representing the temperature of the wafer chuck; a classification unit that applies a learned model that learns the correspondence between the characteristics of changes in chuck temperature and a specified number of temperature change patterns into which changes in chuck temperature are classified, and that outputs a temperature change pattern corresponding to the inputted change in chuck temperature when the chuck temperature is input; and a temperature control parameter setting unit that derives temperature control parameters corresponding to the temperature change pattern output from the classification unit when the chuck temperature is input to the classification unit, and sets the temperature control parameters. The temperature control parameter setting unit is applied to control the operation of the chuck temperature adjustment unit that adjusts the chuck temperature.

[0037] According to the prober of the present disclosure, it is possible to obtain the same operational effects as those of the temperature control device of the present disclosure.

[0038] In the prober according to the present disclosure, the same features as those specified in any one of the second to fifth aspects can be appropriately combined. In this case, the components performing the processes or functions specified in the temperature control device can be understood as the components of the prober performing the corresponding processes or functions.

[0039] A learning model generation method according to a ninth aspect of the present disclosure is a learning model generation method that generates a trained model that learns the correspondence between characteristics of changes in chuck temperature, which is the temperature of a wafer chuck that holds a wafer on which a plurality of semiconductor chips are formed, and a specified number of temperature change patterns into which the changes in chuck temperature are classified.

[0040] According to the learning model generation method of the present disclosure, it is possible to provide a learned model to be applied to the temperature control device of the present disclosure. Effect of the Invention

[0041] According to the present invention, a classification unit to which a trained model that has learned the correspondence between the characteristics of changes in chuck temperature and the patterns of changes in chuck temperature is applied is used, and when an acquired chuck temperature is input to the classification unit, the temperature control parameters output from the classification unit are applied to a temperature adjustment unit that adjusts the chuck temperature. This makes it possible to automatically adjust the temperature control parameters applied to the chuck temperature adjustment unit that adjusts the chuck temperature based on the chuck temperature. [Brief description of the drawings]

[0042] [Figure 1] FIG. 1 is a schematic diagram of a prober according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of the appearance of the prober shown in FIG. [Diagram 3] FIG. 3 is a top view of the wafer. [Figure 4] FIG. 4 is a functional block diagram showing an electrical configuration of the prober shown in FIG. [Diagram 5] FIG. 5 is a functional block diagram showing an example of the configuration of the chuck temperature control unit shown in FIG. [Figure 6] FIG. 6 is a functional block diagram showing a modification of the chuck temperature control unit shown in FIG. [Figure 7] FIG. 7 is a schematic diagram of the optimization of temperature control parameters during wafer inspection. [Figure 8] FIG. 8 is a schematic diagram of chuck temperature control parameter adjustment according to the prior art. [Figure 9] FIG. 9 is a diagram illustrating a first pattern of change in the chuck temperature. [Figure 10] FIG. 10 is a diagram illustrating a second pattern of change in the chuck temperature. [Figure 11] FIG. 11 is a diagram illustrating the third pattern of the change in the chuck temperature. [Figure 12] FIG. 12 is a diagram illustrating a fourth pattern of change in the chuck temperature. [Figure 13] FIG. 13 is a schematic diagram of the generation of a trained model applied to classifying patterns of change in chuck temperature. [Figure 14] FIG. 14 is a schematic diagram of classification of patterns of change in chuck temperature to which the trained model shown in FIG. 13 is applied. [Figure 15] FIG. 15 is a schematic diagram showing a specific example of chuck temperature control. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification, the same components are given the same reference numerals, and duplicated descriptions will be omitted as appropriate.

[0044] [Example of the configuration of the prober according to the embodiment] Fig. 1 is a schematic diagram of a prober according to an embodiment. Fig. 2 is an external perspective view of the prober shown in Fig. 1. Fig. 3 is a top view of a wafer. The prober 10 shown in Figs. 1 and 2 is used in a wafer test system that inspects electrical characteristics of a plurality of semiconductor chips formed on a wafer. Fig. 3 shows a wafer W inspected using the prober 10.

[0045] This figure shows the upper surface of a wafer W supported by a wafer chuck 20. A plurality of semiconductor chips 9 are formed on the wafer W. Each semiconductor chip 9 is formed with a plurality of electrode pads 9a.

[0046] The prober 10 shown in Figures 1 and 2 includes a base 12, a Y stage 13, a Y moving section 14, an X stage 15, an X moving section 16, a Zθ stage 17, a Zθ moving section 18, and a wafer chuck 20, all shown in Figure 1. The prober 10 also includes a support 23, a head stage 24, a card holder 25, and a probe card 26, all shown in Figure 2. The prober 10 also includes a wafer alignment camera 29, an upper and lower stages 30, a needle alignment camera 31, a cleaning plate 32, and a temperature sensor 34, all shown in Figure 1. The configuration of the prober 10 is not limited to the example shown in Figures 1 and 2, and can be modified as appropriate.

[0047] On the upper surface of the base 12, the Y stage 13 is supported so as to be movable in the Y-axis direction by using a Y moving section 14. The Y moving section 14 moves the Y stage 13 on the upper surface of the base 12 in the Y-axis direction.

[0048] The Y moving unit 14 is, for example, a guide rail arranged on the upper surface of the base 12, a guide rail parallel to the Y axis, a slider arranged on the lower surface of the Y stage 13, and includes a slider that engages with the guide rail, and an actuator such as a motor that moves the Y stage 13 in the Y axis direction.

[0049] On the upper surface of Y stage 13, X stage 15 is supported so as to be movable in the X-axis direction by X moving section 16. X moving section 16 moves X stage 15 on the upper surface of Y stage 13 in the X-axis direction.

[0050] The X-movement unit 16 is, for example, a guide rail arranged on the upper surface of the Y-stage 13, which is a guide rail parallel to the X-axis, a slider arranged on the lower surface of the X-stage 15, which engages with the guide rail, and an actuator such as a motor that moves the X-stage 15 in the X-axis direction.

[0051] A Zθ stage 17 and a vertical stage 30 are disposed on the upper surface of the X stage 15. The Zθ stage 17 includes a Zθ moving part 18. A wafer chuck 20 is supported on the upper surface of the Zθ stage 17.

[0052] The Zθ moving unit 18 includes, for example, a lifting mechanism that lifts and lowers the Zθ stage 17 and a rotation mechanism that rotates the Zθ stage 17 around a rotation axis parallel to the Z axis. The Zθ moving unit 18 moves the wafer chuck 20 supported on the upper surface of the Zθ stage 17 in the Z axis direction and rotates the wafer chuck 20 around a rotation axis parallel to the Z axis.

[0053] The wafer W is supported on the upper surface of the wafer chuck 20 by applying various supporting methods such as vacuum suction. The wafer chuck 20 also includes a chuck temperature adjustment unit 20a. The chuck temperature adjustment unit 20a adjusts the temperature of the wafer chuck 20 to adjust the temperature of the wafer W supported by the wafer chuck 20.

[0054] Chuck temperature adjustment unit 20a may be implemented by a known mechanism such as a heater mechanism, a chiller mechanism, or a heat pump mechanism. The operation of chuck temperature adjustment unit 20a is controlled based on a command signal sent from a chuck temperature control unit. The chuck temperature control unit is illustrated in FIG. 4 with reference numeral 21. Note that chuck temperature adjustment unit 20a described in the embodiment is an example of a chuck temperature adjustment device that adjusts the temperature of a wafer chuck.

[0055] The wafer chuck 20 is supported by the above-mentioned Zθ stage 17 etc. so as to be movable in the X, Y and Z axis directions and to be rotatable about a rotation axis parallel to the Z axis. The above-mentioned Zθ stage 17 etc. function as a relative moving unit that moves the wafer W supported by the wafer chuck 20 and the probe needles 35 relatively in the X, Y, Z directions and rotation direction.

[0056] 2 is provided on the upper surface of the base 12, and supports the head stage 24 at a position above the Y stage 13, the X stage 15, and the Zθ stage 17. In other words, the head stage 24 is fixed to the upper surface of the base 12 using the support 23.

[0057] A card holder 25 is provided in the center of the head stage 24. The card holder 25 is formed with a holding hole 25a for holding the outer periphery of a probe card 26. The probe card 26 is inserted into the holding hole 25a of the probe card 26, and is supported at a position facing the wafer W by using the head stage 24 and the card holder 25. The holding hole 25a is illustrated in FIG.

[0058] 1 includes probe needles 35 arranged according to the arrangement of electrode pads 9a of the semiconductor chip 9 to be tested. The card holder 25 and the probe card 26 are replaced according to the type of the semiconductor chip 9.

[0059] The probe card 26 is provided with connection terminals that are electrically connected to the probe needles 35. A tester is connected to the connection terminals. The tester supplies various test signals to the electrode pads 9a of the semiconductor chip 9 via the connection terminals of the probe card 26 and the probe needles 35, and receives signals output from the electrode pads 9a. The tester analyzes the signals output from the electrode pads 9a and tests whether the semiconductor chip 9 operates normally. Publicly known techniques can be applied to the configuration and testing method of the tester. A detailed description of the configuration of the tester, etc. will be omitted here. Illustrations of the connection terminals and the tester will be omitted.

[0060] Wafer alignment camera 29 photographs the semiconductor chip 9 of wafer W supported by wafer chuck 20. The photographed image of semiconductor chip 9 photographed by wafer alignment camera 29 is used to detect the position of electrode pad 9a of semiconductor chip 9 to be inspected. The position where wafer alignment camera 29 is disposed and the structure of wafer alignment camera 29 are not particularly limited.

[0061] The vertical stage 30 is equipped with a needle alignment camera 31 and a cleaning plate 32. The needle alignment camera 31 and the cleaning plate 32 are disposed at positions facing the probe card 26 and the like. The vertical stage 30 is also equipped with a lifting mechanism that supports the needle alignment camera 31 and the cleaning plate 32 so as to be movable in the Z-axis direction. The vertical stage 30 can adjust the positions of the needle alignment camera 31 and the cleaning plate 32 in the Z-axis direction by operating the lifting mechanism. Note that the lifting mechanism that is movable in the Z-axis direction is not shown in the figure.

[0062] The needle positioning camera 31 and the cleaning plate 32 are configured to be movable in the Y-axis direction by using the Y-stage 13 and the Y-moving unit 14 via the upper and lower stages 30, and are supported to be movable in the X-axis direction by using the X-stage 15 and the X-moving unit 16. That is, the needle positioning camera 31 and the cleaning plate 32 are configured to be movable relative to the probe needle 35 in the X-axis, Y-axis and Z-axis directions.

[0063] Needle alignment camera 31 photographs probe needle 35. The image of probe needle 35 photographed by needle alignment camera 31 is used to detect the tip position of probe needle 35. Specifically, the XY coordinates of the tip position of probe needle 35 are detected based on the position coordinates of needle alignment camera 31, and the Z coordinate of the tip position of probe needle 35 is detected based on the focal position of needle alignment camera 31.

[0064] When the semiconductor chips 9 of the wafer W are inspected, the tip positions of the probe needles 35 are detected every time the probe card 26 is replaced. The tip positions of the probe needles 35 may be detected every time a specified number of semiconductor chips 9 are inspected.

[0065] To detect the tip position of probe needle 35, needle positioning camera 31 is moved to a photographing position of the tip position of probe needle 35, and needle positioning camera 31 is used to photograph the tip position of probe needle 35.The tip position of probe needle 35 is detected based on the photographed image of the tip position of probe needle 35.

[0066] Furthermore, detection is performed of the positions of the electrode pads 9a of the semiconductor chip 9 on the wafer W to be inspected which is supported by the wafer chuck 20. Specifically, the wafer alignment camera 29 is moved to an imaging position of the electrode pads 9a of the semiconductor chip 9 on the wafer W to be inspected, the electrode pads 9a are imaged using the wafer alignment camera 29, and the positions of the electrode pads 9a are detected based on the image of the electrode pads 9a.

[0067] Then, the probe needles 35 are brought into electrical contact with the electrode pads 9a of the semiconductor chip 9 that is the first subject of testing, and the semiconductor chip 9 that is the first subject of testing is tested using a tester.

[0068] Thereafter, the wafer W to be inspected is moved, and the probe needles 35 are electrically contacted with the electrode pads 9a of the semiconductor chip 9 to be inspected next, and the semiconductor chip 9 to be inspected is inspected. By repeating this procedure, inspections are sequentially performed on the multiple semiconductor chips 9 to be inspected. The tips of the probe needles 35 are appropriately cleaned and polished using the cleaning plate 32.

[0069] As a specific inspection method for the semiconductor chip 9, for example, a known inspection method such as the inspection method described in JP 2018-117095 A may be applied. Here, a detailed description of the inspection method for the semiconductor chip 9 will be omitted.

[0070] The temperature sensor 34 is provided at a position facing the lower surface of the card holder 25 and the lower surface of the probe card 26. The lower surface of the card holder 25 is the surface opposite to the surface of the card holder 25 on which the probe card 26 is supported. The lower surface of the probe card 26 is the surface of the probe card 26 that is supported by the card holder 25.

[0071] Examples of the location of the temperature sensor 34 include the side surface of the Zθ stage 17 and the side surface of the vertical stage 30. The temperature sensor 34 is supported by the Y stage 13, the X stage 15, the Zθ stage 17, and the vertical stage 30 so as to be freely movable relative to the card holder 25 and the probe card 26.

[0072] For example, a non-contact temperature sensor using a radiant energy detection method is applied as the temperature sensor 34, and can perform non-contact measurement of the temperatures of the card holder 25 and the probe card 26. The card holder 25 and the probe card 26 can be thermally deformed by the influence of the temperature of the wafer chuck 20. As the card holder 25 and the like are thermally deformed, the tip positions of the probe needles 35 are displaced from their specified positions.

[0073] The prober 10 may use the temperature sensor 34 to measure the temperatures of the card holder 25 and the probe card 26, and predict the displacement of the tip positions of the probe needles 35 due to thermal deformation of the card holder 25, etc. For example, the prober 10 may predict the displacement amount and displacement direction of the tip positions of the probe needles 35 as the displacement of the tip positions of the probe needles 35.

[0074] [Example of electrical configuration of the prober according to the embodiment] Fig. 4 is a functional block diagram showing the electrical configuration of the prober shown in Fig. 1. Fig. 4 mainly shows functions related to temperature control of the wafer chuck 20 and functions related to contact control between the probe needles 35 and the electrode pads 9a of the semiconductor chips 9 on the wafer W, and other functions are omitted as appropriate.

[0075] The control device 40 controls each part of the prober 10. A computer is used as the control device 40. The control device 40 executes various programs corresponding to the functions of each part of the prober 10 to realize the functions of each part of the prober 10. The control device 40 may be disposed in the main body of the prober 10 or may be disposed outside the prober 10.

[0076] The computer may be in the form of a server, a personal computer, a workstation, a tablet terminal, etc. The computer may be in the form of a virtual machine.

[0077] The various programs may be stored in a storage device provided in the control device 40, or may be stored in a storage device provided inside the prober 10, which is external to the control device 40. The control device 40 may obtain the various programs from a storage device external to the prober 10.

[0078] The control device 40 includes an arithmetic circuit including various processors and memories, etc. Examples of the various processors include a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), and a programmable logic device.

[0079] Examples of programmable logic devices include SPLDs (Simple Programmable Logic Devices), CPLDs (Complex Programmable Logic Devices), and FPGAs (Field Programmable Gate Arrays). The various functions of the control device 40 may be realized using one processor or multiple processors. The multiple processors may be multiple processors of the same type or multiple processors of different types.

[0080] The control device 40 includes various communication interfaces. The control device 40 is communicatively connected to peripheral devices such as the wafer alignment camera 29, the needle alignment camera 31, and the temperature sensor 34 via the various communication interfaces. The communication interfaces may use various standards such as USB (Universal Serial Bus). The communication form of the communication interfaces may be either wired communication or wireless communication.

[0081] The control device 40 includes a chuck temperature control unit 21. The chuck temperature control unit 21 controls the operation of a chuck temperature adjustment unit 20a provided in the wafer chuck 20. The chuck temperature control unit 21 acquires the chuck temperature from a chuck temperature sensor 20b provided in the wafer chuck 20. The details of the chuck temperature control unit 21 will be described later.

[0082] The control device 40 includes a card temperature acquisition unit 42. The card temperature acquisition unit 42 acquires the temperature of the card holder 25 and the temperature of the probe card 26 output from the temperature sensor 34. The card temperature acquisition unit 42 includes a communication interface corresponding to the output signal output from the temperature sensor 34.

[0083] The control device 40 includes a needle position acquisition unit 44. The needle position acquisition unit 44 acquires a photographed image of the tip position of the probe needle 35 output from the needle positioning camera 31. The needle position acquisition unit 44 acquires information on the tip position of the probe needle 35 from the photographed image of the tip position of the probe needle 35. Acquiring information may include the concept of processing original information to generate desired information.

[0084] The control device 40 includes a movement control unit 52. The movement control unit 52 controls the operation of the X movement unit 16 to drive the X stage 15. The movement control unit 52 controls the operation of the Y movement unit 14 to drive the Y stage 13. The movement control unit 52 controls the operation of the Zθ movement unit 18 to drive the Zθ stage 17.

[0085] The movement control unit 52 acquires the position of the semiconductor chip 9 to be inspected from the captured image of the semiconductor chip 9 to be inspected transmitted from the wafer alignment camera 29. The movement control unit 52 also acquires information on the tip positions of the probe needles 35 from the needle position acquisition unit 44.

[0086] When inspecting the wafer W, the movement control unit 52 drives the X-stage 15, the Y-stage 13, and the Zθ-stage 17 to move the wafer W relative to the probe needles 35, and brings the multiple semiconductor chips 9 to be inspected into contact with the probe needles 35 in sequence.

[0087] The movement control unit 52 may acquire the temperature of the card holder 25 and the temperature of the probe card 26 using the card temperature acquisition unit 42, and correct fluctuations in the tip position of the probe needle 35 caused by temperature changes such as the temperature of the card holder 25.

[0088] Control device 40 includes wafer information acquisition unit 54. Wafer information acquisition unit 54 acquires wafer information that identifies the type of wafer W to be inspected. The wafer information includes information on the type of semiconductor chips 9 formed on wafer W. Chuck temperature controller 21 controls the chuck temperature based on the wafer information acquired using wafer information acquisition unit 54. Wafer information acquisition unit 54 may be a component of chuck temperature controller 21.

[0089] [Example of chuck temperature control unit configuration] Fig. 5 is a functional block diagram showing an example of the configuration of the chuck temperature controller shown in Fig. 4. Chuck temperature controller 21 may be configured as a temperature control device to which a computer is applied. The computer functioning as the temperature control device may be the same as the computer functioning as controller 40 shown in Fig. 4.

[0090] 5 uses the chuck temperature to automatically adjust the chuck temperature control parameters applied to the chuck temperature adjustment unit 20a. The chuck temperature control unit 21 is provided with a learned learning model.

[0091] Chuck temperature control unit 21 includes a chuck temperature acquisition unit 100, a classification unit 102, a learned model storage unit 103, and a chuck temperature control parameter setting unit 104. Chuck temperature acquisition unit 100 acquires the chuck temperature by applying a predefined sampling period.

[0092] The classification unit 102 classifies the change in chuck temperature into one temperature change pattern included in a plurality of predefined temperature change patterns based on the chuck temperature acquired using the chuck temperature acquisition unit 100. The classification unit 102 applies a learned model obtained by performing supervised learning using the relationship between the characteristics of the change in chuck temperature and the temperature change pattern as learning data.

[0093] The trained model storage unit 103 stores one or more trained models to be applied to the classification unit 102. The classification unit 102 reads out the trained model from the trained model storage unit 103 and classifies the change in chuck temperature.

[0094] The trained model storage unit 103 may store a plurality of trained models corresponding to a plurality of types of wafers W. The classification unit 102 may select one trained model corresponding to the wafer information of the inspection target acquired using the wafer information acquisition unit 54, and classify the change in the chuck temperature.

[0095] The trained model stored in trained model storage unit 103 may be generated using a computer. The computer used to generate the trained model may be a device external to chuck temperature control unit 21, or may be a device provided in chuck temperature control unit 21.

[0096] The chuck temperature control parameter setting unit 104 acquires the temperature change pattern output from the classification unit 102 in response to the input of the chuck temperature, and derives a chuck temperature control parameter corresponding to the temperature change pattern.

[0097] The chuck temperature control parameter setting unit 104 includes a heating control parameter derivation unit 110 that derives heating control parameters and a cooling control parameter derivation unit 112 that derives cooling control parameters.

[0098] The chuck temperature control parameter setting unit 104 sets heating control parameters and cooling control parameters as chuck temperature control parameters for the chuck temperature adjustment unit 20a.

[0099] In this embodiment, a PID control parameter is exemplified as an example of the chuck temperature control parameter. The heating control PID shown in Fig. 5 is a heating control parameter derivation unit 110, and means that a PID control parameter is derived as a heating control parameter applied to heating control. The cooling control PID shown in the same figure is a cooling control parameter derivation unit 112, and means that a PID control parameter is derived as a cooling control parameter applied to cooling control. Note that P in PID is the initial letter of Proportional, I is the initial letter of Integral, and D is the initial letter of Derivative.

[0100] Fig. 6 is a functional block diagram showing a modified example of the chuck temperature controller shown in Fig. 5. Chuck temperature controller 21a shown in Fig. 6 includes a chuck temperature control parameter setting unit 104a instead of chuck temperature control parameter setting unit 104 shown in Fig. 5.

[0101] The chuck temperature control parameter setting unit 104a includes a heating control parameter derivation unit 110a and a cooling control parameter derivation unit 112a. The heating control parameter derivation unit 110a acquires a temperature change pattern output from the classification unit 102, and derives heating control parameters corresponding to the temperature change pattern. The heating control parameter derivation unit 110a also derives a cooling control amount based on the heating control parameters.

[0102] The cooling control parameter derivation unit 112a acquires the cooling control amount from the heating control parameter derivation unit 110a and derives the cooling control parameter based on the cooling control amount. The chuck temperature control parameter setting unit 104a sets the heating control parameter and the cooling control parameter as the chuck temperature control parameters for the chuck temperature adjustment unit 20a.

[0103] [Example of chuck temperature control during wafer inspection] FIG. 7 is a schematic diagram of the optimization of temperature control parameters during wafer inspection. In FIG. 7, the change in chuck temperature is illustrated in a graph format in which the horizontal axis represents time and the vertical axis represents chuck temperature. During the inspection time of one semiconductor chip 9, the chuck temperature is acquired multiple times, and the change in chuck temperature is acquired as shown in graph G10, etc. The temperature range parallel to the time axis shown in graph G10, etc. indicates the allowable temperature range of the chuck temperature during the inspection of the wafer W.

[0104] The first contact shown in Fig. 7 represents an inspection of the semiconductor chip 91. In the inspection of the semiconductor chip 91, the initial values ​​of the specified chuck temperature control parameters are applied, and the temperature of the wafer chuck 20 is controlled. Note that the curves such as graph G10 shown in Fig. 8 are imaginary curves representing the temperature history.

[0105] Graph G10 shows the change in chuck temperature acquired during the inspection of the semiconductor chip 91. The period during the inspection of the semiconductor chip 91 refers to the period from when the probe needles 35 come into contact with the semiconductor chip 91 to when the tester finishes the measurement and the probe needles 35 are released from contact with the semiconductor chip 91.

[0106] Measurement of the chuck temperature during inspection of the semiconductor chip 91 is performed as a background process of the inspection of the semiconductor chip 91. Measurement of the chuck temperature does not have to be performed in response to contact between the semiconductor chip 9 and the probe needle 35. Furthermore, for inspection of a plurality of semiconductor chips 9, sampling of the chuck temperature may be performed continuously at a constant sampling period.

[0107] The chuck temperature during inspection of semiconductor chip 91 may deviate from the allowable temperature range, and adjustment of the chuck temperature control parameters is performed. Chuck temperature control parameter setting unit 104 shown in Fig. 5 derives chuck temperature control parameters corresponding to the change in chuck temperature shown as graph G10 in Fig. 7, and sets the derived chuck temperature control parameters for chuck temperature adjustment unit 20a.

[0108] In the inspection of the semiconductor chip 92 illustrated as the second contact, new chuck temperature control parameters are set and temperature control of the wafer chuck 20 is performed. Graph G12 represents the change in chuck temperature obtained during the inspection of the semiconductor chip 92.

[0109] The chuck temperature during inspection of semiconductor chip 92 is improved compared to the chuck temperature during inspection of semiconductor chip 91, but may fall outside the allowable temperature range. Chuck temperature control parameter setting unit 104 derives chuck temperature control parameters corresponding to the change in chuck temperature shown as graph G12 in Fig. 7, and sets the obtained chuck temperature control parameters for chuck temperature adjustment unit 20a.

[0110] In the inspection of the semiconductor chip 93 shown as the third contact, new chuck temperature control parameters are set and temperature control of the wafer chuck 20 is performed. Graph G14 represents the change in chuck temperature obtained during the inspection of the semiconductor chip 93.

[0111] The chuck temperature during inspection of semiconductor chip 93 is improved compared to the chuck temperature during inspection of semiconductor chip 92, and is kept within the allowable temperature range. In this manner, the chuck temperature control parameters are updated and optimized each time contact is made. As a result, the chuck temperature control parameters optimal for the wafer to be inspected are selected, and the temperature control of wafer chuck 20 is performed.

[0112] Fig. 8 is a schematic diagram of chuck temperature control parameter adjustment according to the prior art. Fig. 8 uses a graph format to illustrate the change in chuck temperature. Note that the horizontal axis of graphs G1, G2, and G3 shown in Fig. 8 represents time, and the vertical axis of graphs G1, etc. represents chuck temperature.

[0113] In the conventional temperature control of the wafer chuck 20, an operator grasps the change in the chuck temperature and determines the PID control parameters (K p ,K i ,K d ) adjustments were being made.

[0114] For example, as shown in graph G1, when chuck temperatures Tc11, Tc12, and Tc13 are acquired at sampling timings t11, t12, and t13, respectively, the PID control parameters (K p ,K i ,K d ) p parameter K p , i parameter K i and d parameter K d For each of these, an adjustment coefficient C based on the operator's experience is p , adjustment coefficient C i and adjustment coefficient C d is derived, and the adjustment factor (C p ,C i ,C d ) is multiplied by the new PID control parameter (C p ×K p,C i ×K i ,C d ×K d ) is set.

[0115] Furthermore, as shown in graph G2, when the chuck temperatures Tc21, Tc22, and Tc23 are acquired at sampling timings t21, t22, and t23, respectively, the d parameter K d , and the adjustment coefficient C based on the operator's experience. d Furthermore, as shown in graph G3, when the chuck temperatures Tc31, Tc32, and Tc33 are acquired at sampling timings t31, t32, and t33, respectively, the i parameter K i , and the adjustment coefficient C based on the operator's experience. i That is, in the chuck temperature control according to the conventional technology, the chuck temperature control parameters are set based on the empirical viewpoint of the operator using one or more chuck temperatures obtained during the inspection of the wafer W.

[0116] [Explanation of the learning model applied to the classification part] The chuck temperature controller 21 according to this embodiment applies machine learning to automatically adjust the chuck temperature control parameters. The machine learning applied to the chuck temperature controller 21 will be described in detail below.

[0117] Although three types of chuck temperature changes are illustrated in FIG. 8, there are an infinite number of types of chuck temperature changes. Machine learning that targets all of the infinite number of chuck temperature changes is difficult. Therefore, a trained model that classifies chuck temperature changes into multiple patterns is generated, and the trained model is applied to the classification unit 102 shown in FIG. 5.

[0118] Fig. 9 is an explanatory diagram of a first pattern of change in chuck temperature. Fig. 9 illustrates the change in chuck temperature in a graph format in which the horizontal axis represents time and the vertical axis represents chuck temperature. Graphs G20, G22, G24, and G26 shown in Fig. 9 each represent a first pattern in which the chuck temperature hunts.

[0119] Fig. 10 is an explanatory diagram of the second pattern of chuck temperature change. Fig. 10 illustrates the change in chuck temperature using a graph format similar to that of Fig. 9. Graphs G30, G32, and G34 shown in Fig. 10 each represent the second pattern in which the convergence time of the chuck temperature change is long.

[0120] Fig. 11 is an explanatory diagram of the third pattern of chuck temperature change. Fig. 11 illustrates the change in chuck temperature using a graph format similar to that of Fig. 9 and Fig. 10. Graphs G40, G42, G44, and G46 shown in Fig. 11 each represent the third pattern in which the change in chuck temperature is large.

[0121] Fig. 12 is an explanatory diagram of a fourth pattern of change in chuck temperature. In Fig. 12, the change in chuck temperature is illustrated using a graph format similar to that of Figs. 9 to 11. Graph G50 shown in Fig. 12 represents the fourth pattern in which the chuck temperature is stable.

[0122] Fig. 13 is a schematic diagram of a trained model generation applied to classifying patterns of change in chuck temperature. First, a plurality of temperature change samples representing changes in chuck temperature are represented using a fixed number of feature quantities, and a label is attached to the temperature change pattern of the chuck temperature. Fig. 13 illustrates temperature change sample SP1, temperature change sample SP2, temperature change sample SP3, temperature change sample SP4, temperature change sample SP5, and temperature change sample SP6 as examples of the plurality of temperature change samples.

[0123] Considerations for characterizing the change in chuck temperature include the direction in which the temperature change begins, the time until the temperature change converges, the area of ​​the temperature outside the allowable temperature range, the number of inflection points of the temperature change, the frequency of the temperature change, and the number of times the temperature falls outside the allowable temperature range.

[0124] The direction of the start of the temperature change is derived from the temperature measurement value at the first sampling and the temperature measurement value at the second sampling. The direction of the start of the temperature change may be a positive direction in which the temperature increases and a negative direction in which the temperature decreases.

[0125] The area of ​​the temperature outside the allowable temperature range is the area of ​​the part of the curve representing the temperature change that is outside the allowable temperature range PR. The number of inflection points of the temperature change is the number of inflection points on the curve representing the temperature change. The frequency of the temperature change is the frequency on the curve representing the temperature change, and is derived by applying a Fourier transform to the curve representing the temperature change.

[0126] 13, the temperature change samples SP1 and SP2 are labeled with a first pattern indicating that the change in chuck temperature is hunting. Similarly, the temperature change samples SP3 and SP4 are labeled with a second pattern indicating that the convergence time of the change in chuck temperature is long, and the temperature change samples SP5 and SP6 are labeled with a third pattern indicating that the change in chuck temperature is large.

[0127] Trained model 200 is generated by performing training using pairs of feature amounts representing temperature changes and temperature change patterns into which changes in chuck temperature are classified as training data. When the feature amounts of changes in chuck temperature are input, trained model 200 outputs a temperature change pattern corresponding to the feature amounts of changes in chuck temperature.

[0128] Examples of supervised machine learning algorithms applied to the trained model 200 include k-nearest neighbor methods, decision trees such as classification trees, random forests, nonlinear SVMs, and neural networks. Note that SVM is an abbreviation for Support-Vector Machine.

[0129] The trained model 200 is generated by performing training for each type of wafer W. The trained models 200 corresponding to each of the multiple types of wafer W are assigned the type of wafer W as an index.

[0130] 5 may include a feature derivation unit that derives a feature corresponding to the change in chuck temperature from the change in chuck temperature. That is, classification unit 102 may include the feature derivation unit, and when the change in chuck temperature is input, may output a temperature change pattern corresponding to the change in chuck temperature. The feature derivation unit may be a component of classification unit 102.

[0131] Furthermore, chuck temperature control unit 21 may include a chuck temperature change derivation unit that derives a change in chuck temperature from multiple chuck temperatures acquired in chronological order. That is, classification unit 102 may include a chuck temperature change derivation unit and, when multiple chuck temperatures are input in chronological order, may output a temperature change pattern corresponding to the change in chuck temperature.

[0132] That is, classification unit 102 may include a chuck temperature change derivation unit that derives a change in chuck temperature corresponding to the format of input data representing the input chuck temperature. Trained model 200 may be understood as a trained model that has learned the relationship between the characteristics of the change in chuck temperature and the pattern of the change in chuck temperature. Note that trained model 200 described in the embodiment is an example of a trained model that has learned the correspondence between the characteristics of the change in chuck temperature and the temperature change pattern into which the change in chuck temperature is classified.

[0133] Each of the multiple patterns of chuck temperature change is associated with an adjustment coefficient that is applied to the chuck temperature control parameter. In the example shown in FIG. 13, the first pattern in which the change in chuck temperature is hunting includes an adjustment coefficient that is applied to the chuck temperature control parameter (K p ,K i ,K d1 ) adjustment factor (C p1 ,C i1 ,C d1 Similarly, the second pattern, which has a long convergence time for the change in the chuck temperature, is assigned an adjustment coefficient (C p2 ,C i2 ,C d2 ) is associated with the third pattern, which has a large change in chuck temperature, and the adjustment coefficient (C p3 ,C i3 ,C d3 ) is associated.

[0134] The relationship between the chuck temperature change pattern and the adjustment coefficient is as follows: p ,K i ,K d ) is repeatedly adjusted, and the final stable chuck temperature control parameter is derived from the relationship between the initial value of the chuck temperature control parameter. Note that the procedure for generating trained model 200 described in the embodiment is an example of a trained model generation method.

[0135] [Operation of trained models] Fig. 14 is a schematic diagram of classification of patterns of change in chuck temperature to which the trained model shown in Fig. 13 is applied. Fig. 14 shows the procedure of a chuck temperature control method for classifying the chuck temperature into one of a plurality of predefined temperature change patterns and deriving an adjustment coefficient corresponding to the temperature change pattern.

[0136] In the chuck temperature acquisition step S10, the chuck temperature is acquired using a chuck temperature acquisition unit 100 shown in Fig. 5. In the classification step S12, the classification unit 102 shown in Fig. 5 outputs a temperature change pattern corresponding to the change in the chuck temperature. Fig. 14 shows an example in which a score indicating the likelihood of each temperature change pattern is output as the temperature change pattern output 210.

[0137] In the chuck temperature control parameter acquisition step S14, the chuck temperature control parameter setting unit 104 outputs the chuck temperature control parameters corresponding to the temperature change pattern output from the classification unit 102 in the classification step S12. In FIG. 14, a first pattern in which the change in the chuck temperature having the highest score is hunting is adopted as the temperature change pattern, and an adjustment coefficient (C p ,C i ,C d ) is output as follows:

[0138] The chuck temperature control parameter setting unit 104 determines an adjustment coefficient (C p ,C i ,C d ) is applied to the chuck temperature adjustment unit. The step of setting the heating control parameters and the cooling control parameters to the chuck temperature adjustment unit may be included in the chuck temperature control method as a chuck temperature control parameter setting step.

[0139] 14, a step of deriving a change in chuck temperature from a plurality of chuck temperatures acquired in chronological order may be performed. The step of deriving a change in chuck temperature may be performed integrally with the chuck temperature acquisition step S10.

[0140] A step of deriving a feature quantity corresponding to the change in chuck temperature from the change in chuck temperature may be performed after the step of deriving the change in chuck temperature. The step of deriving the feature quantity may be performed integrally with the step of deriving the change in chuck temperature.

[0141] Before the classification step S12, a learning model selection step may be executed in which the type of the wafer W to be measured is determined and a learned model 200 corresponding to the type of the wafer W is selected. The learning model selection step may be executed integrally with the classification step S12.

[0142] [Specific example of chuck temperature control] Fig. 15 is a schematic diagram showing a specific example of chuck temperature control. Like Fig. 7, Fig. 15 shows a case where inspections of a plurality of semiconductor chips 9 included in one wafer W are carried out in sequence.

[0143] For the inspection of the first semiconductor chip 9 illustrated as the first contact, the initial value of the chuck temperature control parameter (K p0 ,K i0 ,K d0 In the first contact, for example, if the change in the chuck temperature is classified as the first pattern of hunting, the adjustment coefficient (C p1 ,C i1 ,C d1 ) is obtained.

[0144] The second contact involves the chuck temperature control parameter (C p1 ×K p0 ,C i1 ×K i0 ,C d1 ×K d0 In the second contact, for example, if the change in the chuck temperature is classified as the second pattern having a long convergence time, the adjustment coefficient (C p2 ,C i2 ,C d2 ) is obtained.

[0145] The third contact is the chuck temperature control parameter (C p1 ×C p2 ×K p0 ,C i1 ×C i2 ×K i0 ,C d1 ×C d2 ×K d015 shows a case where the third contact is classified as the fourth pattern in which the chuck temperature is stable.

[0146] From the fourth contact onwards, the chuck temperature control parameter (C p1 ×C p2 ×K p0 ,C i1 ×C i2 ×K i0 ,C d1 ×C d2 ×K d0 ), the adjustment coefficient (1,1,1) corresponding to the fourth pattern in which the chuck temperature is stable is applied. The adjustment coefficient (1,1,1) is applied when the chuck temperature control parameters of the previous contact are not changed.

[0147] That is, the chuck temperature control parameter (K p0 ,K i0 ,K d0 ) and finally the adjustment coefficient (C p1 ×C p2 ,C i1 ×C i2 ,C d1 ×C d2 ) is applied, a chuck temperature control is implemented that achieves a stable chuck temperature.

[0148] Therefore, if re-learning of the trained model 200 is performed using the change in chuck temperature acquired during the first contact and the adjustment coefficient of the chuck temperature control parameter that realizes a stable chuck temperature, it is possible to realize chuck temperature control with even higher accuracy. Automatic adjustment of the chuck temperature control parameter to which machine learning is applied can be handled by increasing the explanatory variables even when the combination of PID control loops changes and the number of PID control loops increases.

[0149] The first time shown in FIG. 15 is understood as the nth time when n is an integer. The second time shown in FIG. 15 is understood as the jth time when j is an integer greater than n. The third time shown in FIG. 15 is understood as the kth time when k is an integer greater than j. The chuck temperature control parameter in the nth contact is the initial value (K p0 ,K i0 ,K d0 ) with the adjustment coefficient (C p ,C i ,C d ) may be applied.

[0150] [Variations of chuck temperature control] In the inspection of wafer W shown in FIG. 7, when inspection of semiconductor chip 94 is performed after inspection of semiconductor chip 93, and a change in chuck temperature shown as graph G14 is obtained during inspection of semiconductor chip 94, chuck temperature control unit 21 shown in FIG. 5 may not update the chuck temperature control parameters.

[0151] That is, chuck temperature controller 21 may determine whether the chuck temperature acquired during inspection of wafer W is outside a specified allowable temperature range, and if the chuck temperature is outside the specified allowable temperature range, update of the chuck temperature control parameters may be performed. Also, if the chuck temperature is within the specified allowable temperature range, update of the chuck temperature control parameters may not be performed.

[0152] [Example of the configuration of a program executed by a computer] The various functions of chuck temperature controller 21 shown in Fig. 5 are realized by a computer executing a program. Examples of the various functions realized by a computer include a function of acquiring the chuck temperature, a function of classifying changes in the chuck temperature into a specified pattern, and a function of acquiring chuck temperature control parameters based on the pattern of changes in the chuck temperature. The program is stored in a non-transitory computer-readable storage medium.

[0153] [Effects of the embodiment] The chuck temperature control applied to the prober according to the embodiment can provide the following advantageous effects.

[0154] [1] Using trained model 200 that has learned the characteristics of the temperature change of wafer chuck 20 and the temperature change pattern of wafer chuck 20, the characteristics of the temperature change of wafer chuck 20 are classified into one of a plurality of predefined temperature change patterns. Temperature control parameters corresponding to the classified temperature change pattern are derived. The derived temperature control parameters are applied to chuck temperature adjustment unit 20a that adjusts the chuck temperature. This realizes automatic temperature adjustment of wafer chuck 20 in response to the temperature change of wafer chuck 20.

[0155] [2] A feature quantity representing the characteristics of the temperature change of the wafer chuck 20 is applied as the characteristic of the temperature change of the wafer chuck 20. The learning model learns the correspondence between the feature quantity representing the characteristics of the temperature change of the chuck temperature and a specified temperature change pattern. When the feature quantity representing the characteristics of the temperature change of the chuck temperature is input, the learned model outputs a temperature change pattern corresponding to the feature quantity. In this way, the countless temperature changes of the chuck temperatures are classified into the predefined temperature change patterns.

[0156] [3] A trained model corresponding to the wafer to be inspected is selected from trained models corresponding to each of a plurality of wafers of different types, thereby classifying the chuck temperature change according to the type of the wafer to be inspected.

[0157] [4] The PID control parameters are applied as the chuck temperature control parameters. The chuck temperature control parameters are the same as the previously set PID control parameters (K p ,K i ,K d ) with the adjustment factor (C p ,C i ,C d ) multiplied by the PID control parameter (Cp ×K p ,C i ×K i ,C d ×K d ) is applied. This realizes chuck temperature control in which new PID control parameters based on the already set PID control parameters are applied.

[0158] [5] The PID control parameters (K p ,K i ,K d ) is multiplied by the adjustment factor (C p ,C i ,C d ) is derived. From this, the chuck temperature control parameters suitable for PID control are derived.

[0159] The above-described embodiment of the present invention may be modified, added, or deleted as appropriate within the scope of the gist of the present invention. The present invention is not limited to the above-described embodiment, and many modifications may be made by a person having ordinary knowledge in the relevant field within the technical concept of the present invention. In addition, the embodiment, modified example, and application example may be implemented in combination as appropriate. [Explanation of symbols]

[0160] 9. Semiconductor Chips 9a Electrode pads 10 Prober 12 Base 13 Y Stage 14 Y moving part 15X Stage 16X moving part 17 Zθ stage 18 Zθ moving part 20 Wafer chuck 20a Chuck temperature control unit 20b Chuck temperature sensor 21 Chuck temperature control unit 21a Chuck temperature control unit 23 Pillar 24 Head Stage 25 Card Holder 25a retaining hole 26 Probe Card 29 Wafer Alignment Camera 30 Upper and Lower Stages 31 Needle alignment camera 32 Cleaning plate 34 Temperature Sensor 35 Probe needle 40 Control device 42 Card temperature acquisition unit 44 Needle position acquisition section 46 Wafer information acquisition unit 52 Movement control section 91 Semiconductor Chips 92 Semiconductor Chips 93 Semiconductor Chips 94 Semiconductor Chips 100 Chuck temperature acquisition unit 102 Classification Department 102a Classification section 103 Acquisition of trained model 104 Chuck temperature control parameter setting section 104a Chuck temperature control parameter setting unit 110 Heating control parameter derivation unit 110a Heating control parameter derivation unit 112 Cooling control parameter derivation part 112a Cooling control parameter derivation section 200 trained models 210 Output G1 Graph G2 Graph G3 Graph G10 Graph G12 Graph G14 Graph G20 Graph G22 Graph G24 Graph G26 Graph G30 Graph G32 Graph G34 Graph G40 Graph G42 Graph G44 Graph G46 Graph G50 Graph SP1 Temperature change sample SP2 Temperature change sample SP3 Temperature change sample SP4 Temperature change sample SP5 Temperature change sample SP6 Temperature change sample W wafer

Claims

1. a chuck temperature acquisition unit that acquires a chuck temperature representing the temperature of a wafer chuck that holds a wafer on which a plurality of semiconductor chips are formed; a classification unit that references a correspondence relationship between the characteristics of the chuck temperature change and a prescribed number of temperature change patterns into which the chuck temperature changes are classified, and outputs, when the chuck temperature is input, the temperature change pattern corresponding to the input characteristics of the chuck temperature change; a temperature control parameter setting unit that derives a temperature control parameter corresponding to the temperature change pattern output from the classification unit when the chuck temperature is input to the classification unit, and sets the temperature control parameter; Equipped with a temperature control device that controls the operation of a chuck temperature adjustment unit that adjusts the chuck temperature by applying the temperature control parameters set using the temperature control parameter setting unit;

2. 2. The temperature control apparatus according to claim 1, further comprising a chuck temperature change deriving unit that derives a change in the chuck temperature from a plurality of the chuck temperatures acquired at different times.

3. a feature amount deriving unit that derives a feature amount of the change in the chuck temperature, 2. The temperature control device according to claim 1, wherein the classification unit refers to a correspondence relationship between a characteristic amount of the chuck temperature change and a prescribed number of temperature change patterns into which the chuck temperature change is classified, and outputs the temperature change pattern corresponding to the characteristic amount of the chuck temperature change that has been input when the chuck temperature is input.

4. The temperature control device according to claim 1 , wherein the temperature control parameter setting unit derives the temperature control parameter using an adjustment coefficient corresponding to the temperature change pattern.

5. The computer acquiring a chuck temperature representative of a temperature of a wafer chuck that holds a wafer having a plurality of semiconductor chips formed thereon; a step of outputting, when the chuck temperature is input, the temperature change pattern corresponding to the inputted characteristic of the change in the chuck temperature by referring to a correspondence relationship between the characteristic of the change in the chuck temperature and a prescribed number of temperature change patterns into which the change in the chuck temperature is classified; deriving a temperature control parameter corresponding to the output temperature change pattern when the chuck temperature is input, and setting the temperature control parameter; applying the temperature control parameters to control operation of a chuck temperature adjustment unit to adjust the chuck temperature; A temperature control method to perform.

6. On the computer, A function of acquiring a chuck temperature representing the temperature of a wafer chuck that holds a wafer on which a plurality of semiconductor chips are formed; a function of referencing a correspondence relationship between the characteristics of the change in the chuck temperature and a prescribed number of temperature change patterns into which the change in the chuck temperature is classified, and outputting the temperature change pattern corresponding to the input characteristics of the change in the chuck temperature when the chuck temperature is input; a function of deriving a temperature control parameter corresponding to the output temperature change pattern when the chuck temperature is input, and setting the temperature control parameter; a function of controlling an operation of a chuck temperature adjustment unit that adjusts the chuck temperature by applying the temperature control parameters; A program to achieve this.

7. a wafer chuck for holding a wafer on which a plurality of semiconductor chips are formed; a probe card having a probe needle; a relative movement unit that moves the wafer chuck relative to the probe needle; a chuck temperature adjustment device for adjusting the temperature of the wafer chuck; and a temperature control device that applies a temperature control parameter to control operation of the chuck temperature adjustment device, The temperature control device includes: a chuck temperature acquisition unit that acquires a chuck temperature representing a temperature of the wafer chuck; a classification unit that references a correspondence relationship between the characteristics of the chuck temperature change and a prescribed number of temperature change patterns into which the chuck temperature changes are classified, and outputs, when the chuck temperature is input, the temperature change pattern corresponding to the input characteristics of the chuck temperature change; a temperature control parameter setting unit that derives a temperature control parameter corresponding to the temperature change pattern output from the classification unit when the chuck temperature is input to the classification unit, and sets the temperature control parameter; a chuck temperature control unit that controls an operation of a chuck temperature adjustment unit that adjusts the chuck temperature by applying the temperature control parameters set using the temperature control parameter setting unit; and A prober equipped with

Images