Temperature calibration structure, temperature calibration system and temperature calibration method

Abstract

The present application relates to a kind of temperature calibration structure, temperature calibration system and temperature calibration method, the equivalent circuit of temperature calibration structure includes: first bipolar transistor, second bipolar transistor, first resistance, second resistance and third resistance;The base of first bipolar transistor, the collector of first bipolar transistor, the base of second bipolar transistor and the collector of second bipolar transistor are all grounded;First resistance and second resistance are connected in series, and the end of first resistance away from second resistance is connected with the emitter of first bipolar transistor;The emitter of second bipolar transistor is connected with one end of third resistance, and the other end of third resistance is connected with the end of second resistance away from first resistance. By setting two bipolar transistors in calibration structure, since bipolar transistor has high sensitivity to temperature, and by setting two bipolar transistors can further amplify temperature trend, to improve the accuracy of temperature calibration.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor, in particular to a temperature calibration structure, a temperature calibration system and a temperature calibration method. BACKGROUND

[0002] Temperature has a very obvious influence on semiconductor process, so the temperature uniformity of chuck for adsorbing wafers of semiconductor machine is required to be high; generally, the temperature of semiconductor machine needs to be calibrated to ensure that the chuck has good temperature uniformity.

[0003] At present, the actual temperature of the chuck at different positions is measured by placing multiple temperature calibrators at different positions of the chuck, and then temperature compensation is performed according to the measurement results. However, the accuracy of the existing temperature calibrators is low, only + / - 0.05℃, and it is difficult to achieve the temperature uniformity of the chuck by the measurement results of the existing temperature calibrators. SUMMARY

[0004] Therefore, it is necessary to provide a temperature calibration structure, a temperature calibration system and a temperature calibration method with high accuracy, which can accurately obtain the temperature difference of the chuck at different positions and provide a basis for accurate compensation of the chuck.

[0005] To achieve the above purpose, in one aspect, the present application provides a temperature calibration structure, comprising:

[0006] The equivalent circuit of the temperature calibration structure comprises a first bipolar transistor, a second bipolar transistor, a first resistor, a second resistor and a third resistor; wherein,

[0007] The base of the first bipolar transistor, the collector of the first bipolar transistor, the base of the second bipolar transistor and the collector of the second bipolar transistor are all grounded;

[0008] The first resistor and the second resistor are connected in series, and one end of the first resistor away from the second resistor is connected to the emitter of the first bipolar transistor;

[0009] One end of the third resistor is connected to the emitter of the second bipolar transistor, and the other end is connected to one end of the second resistor away from the first resistor.

[0010] In one of the embodiments, the conduction current of the second bipolar transistor is N times of the conduction current of the first bipolar transistor, wherein N is greater than 1.

[0011] In one of the embodiments, the value of N is in the range of 5≤N≤15.

[0012] In one of the embodiments, the second resistor has a resistance equal to that of the third resistor, and greater than that of the first resistor.

[0013] In one of the embodiments, the second resistor and the third resistor each has a resistance M times that of the first resistor, where M is greater than 1.

[0014] In one of the embodiments, the value of M ranges from 5 to 30.

[0015] In one of the embodiments, the first bipolar transistor and the second bipolar transistor each comprises a PNP bipolar transistor or each comprises an NPN bipolar transistor.

[0016] In one of the embodiments, the equivalent circuit of the temperature calibration structure further comprises an operational amplifier, the operational amplifier comprising a positive input end, a negative input end and an output end, the positive input end of the operational amplifier being connected between the third resistor and the emitter of the second bipolar transistor, the negative input end of the operational amplifier being connected between the first resistor and the second resistor, and the output end of the operational amplifier being connected to one end of the third resistor away from the second bipolar transistor and one end of the second resistor away from the first resistor.

[0017] The application further provides a temperature calibration system for calibrating a semiconductor machine, the temperature calibration system comprising:

[0018] a plurality of temperature calibration structures as described in any of the above embodiments, the plurality of temperature calibration structures being respectively located at different positions of a test area of the semiconductor machine;

[0019] a measuring device for measuring the temperature calibration structures to obtain a first volt-ampere characteristic curve between a first voltage and a current of the emitter of the first bipolar transistor, and a second volt-ampere characteristic curve between a second voltage and a current of the emitter of the second bipolar transistor, where the first voltage is the sum of a voltage between the base and the emitter of the first bipolar transistor and a voltage across the first resistor, and the second voltage is a voltage between the base and the emitter of the second bipolar transistor;

[0020] a processing module connected to the measuring device, for obtaining a voltage difference between the first voltage and the second voltage varying with temperature under the same emitter current condition according to a linear region of the first volt-ampere characteristic curve and a linear region of the second volt-ampere characteristic curve, and obtaining a temperature at a position of each of the temperature calibration structures based on the voltage difference between the first voltage and the second voltage varying with temperature.

[0021] In one of the embodiments, the processing module obtains a linear relationship between the voltage difference between the first voltage and the second voltage and the temperature under the same emitter current condition according to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve, and obtains the temperature at the position of each temperature calibration structure based on the linear relationship.

[0022] In one of the embodiments, the plurality of temperature calibration structures form an arrangement array on the surface of the semiconductor machine test area, the arrangement array is centrally symmetrically distributed with the center of the semiconductor machine test area, and at least one temperature calibration structure is located at the center of the semiconductor machine test area.

[0023] The present application also provides a temperature calibration method, comprising:

[0024] Placing a plurality of temperature calibration structures as described in any of the above solutions at different positions of a semiconductor machine test area;

[0025] Measuring the temperature calibration structures to obtain a first volt-ampere characteristic curve between a first voltage and the current of the emitter of the first bipolar transistor, and a second volt-ampere characteristic curve between a second voltage and the current of the emitter of the second bipolar transistor; wherein the first voltage is the sum of the voltage between the base and the emitter of the first bipolar transistor and the voltage across the first resistor, and the second voltage is the voltage between the base and the emitter of the second bipolar transistor.

[0026] Obtaining the change of the voltage difference between the first voltage and the second voltage with the temperature under the same emitter current condition according to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve, and obtaining the temperature at the position of each temperature calibration structure based on the change of the voltage difference between the first voltage and the second voltage with the temperature.

[0027] In one of the embodiments, the obtaining the change of the voltage difference between the first voltage and the second voltage with the temperature under the same emitter current condition according to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve, and obtaining the temperature at the position of each temperature calibration structure based on the change of the voltage difference between the first voltage and the second voltage with the temperature comprises:

[0028] The processing module obtains a linear relationship between the voltage difference between the first voltage and the second voltage and the temperature under the same emitter current condition according to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve, and obtains the temperature at the position of each temperature calibration structure based on the linear relationship.

[0029] In one of the embodiments, the linear relationship is a first order function, and the formula is:

[0030] y=kx+b

[0031] wherein y is the voltage difference between the first voltage and the second voltage, k is the slope of the linear relationship, x is the temperature of the position where the temperature calibration structure is located, and b is the intercept of the linear relationship.

[0032] In one of the embodiments, after the plurality of temperature calibration structures are placed at different positions of the semiconductor machine test area, the plurality of temperature calibration structures form an arrangement array on the surface of the semiconductor machine test area, the arrangement array is centrally symmetrically distributed with the center of the semiconductor machine test area as the center, and at least one of the temperature calibration structures is located at the center of the semiconductor machine test area.

[0033] The temperature calibration structure described above, by setting two bipolar transistors in the calibration structure, since the bipolar transistor has high sensitivity to temperature, and by setting two bipolar transistors, the temperature trend can be further amplified, thereby improving the accuracy of temperature calibration, so that the accuracy of temperature calibration can be less than 0.01℃; at the same time, by setting the first resistor, the second resistor and the third resistor, the accuracy of the temperature calibration structure can be adjusted by adjusting the resistance values of the three resistors.

[0034] The calibration structure of the temperature calibration system described above is provided with two bipolar transistors, since the bipolar transistor has high sensitivity to temperature, and by setting two bipolar transistors, the temperature trend can be further amplified, thereby improving the accuracy of temperature calibration; at the same time, by setting the first resistor, the second resistor and the third resistor, the accuracy of the temperature calibration structure can be adjusted by adjusting the resistance values of the three resistors; in this way, when the measuring device is used to measure the calibration structure, a high-precision measurement result can be obtained, and after the processing module processes, a more accurate temperature of the position where each temperature calibration structure is located can be obtained, so that the accuracy of the temperature calibrated by the temperature calibration system can be less than 0.01℃.

[0035] The temperature calibration method described above, since the calibration structure adopted is provided with two bipolar transistors, since the bipolar transistor has high sensitivity to temperature, and by setting two bipolar transistors, the temperature trend can be further amplified, thereby improving the accuracy of temperature calibration; at the same time, by setting the first resistor, the second resistor and the third resistor, the accuracy of the temperature calibration structure can be adjusted by adjusting the resistance values of the three resistors, in this way, when the temperature calibration structure is measured, a high-precision measurement result can be obtained, thereby obtaining a more accurate temperature of the position where the temperature calibration structure is located, the accuracy of the temperature calibrated by the temperature calibration method described above can be less than 0.01℃. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is an equivalent circuit diagram of the temperature calibration structure provided in one embodiment of this application;

[0038] Figure 2 This is a structural block diagram of a temperature calibration system provided in another embodiment of this application;

[0039] Figures 3-4 This is a schematic diagram of the temperature calibration structure in a temperature calibration system provided in another embodiment of this application, positioned on different areas of the suction cup surface.

[0040] Figure 5 This refers to the current-voltage characteristic curves of a temperature calibration system provided in another embodiment of this application, where both the first and second bipolar transistors are PNP bipolar transistors, under a given temperature condition; wherein, Figure 5 Curve ① in the figure is the first current-voltage characteristic curve. Figure 5 Curve ② in the figure is the second current-voltage characteristic curve;

[0041] Figure 6 In another embodiment of the temperature calibration system provided in this application, when the resistance value of the second resistor is equal to the resistance value of the third resistor, the voltage difference between the first voltage and the second voltage corresponding to the different resistance values ​​of the second resistor and the third resistor compared to the resistance value of the first resistor shows a linear relationship with the temperature change; wherein, Figure 6 Curve ① in the figure shows the linear relationship between the voltage difference between the first voltage and the second voltage and temperature change when the resistance ratio of the second resistor to the third resistor is 1 and the resistance ratio of the first resistor is the same. Figure 6 Curve ② in the figure shows the linear relationship between the voltage difference between the first voltage and the second voltage and the temperature change when the resistance ratio of the second resistor to the third resistor is 10:1. Figure 6 Curve ③ in the figure shows the linear relationship between the voltage difference between the first voltage and the second voltage and the temperature change when the resistance ratio of the second resistor and the third resistor to the first resistor is 20.

[0042] Figure 7 This is a flowchart of a temperature calibration method provided in another embodiment of this application.

[0043] Reference Signs List:

[0044] 1 - temperature calibration structure, 11 - operational amplifier, 2 - measuring device, 3 - processing module, 4 - suction cup. DETAILED DESCRIPTION

[0045] For the purpose of promoting an understanding of the present application, the present application will now be described in greater detail with reference to the relevant drawings. The embodiments of the present application are illustrated in the drawings. However, the present application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the present application to those skilled in the art.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0047] It should be understood that the terms "first", "second" and so on used herein can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from the other element. For example, without departing from the scope of the present application, the first power input can be referred to as the second power input, and similarly, the second power input can be referred to as the first power input. The first power input and the second power input are both power inputs, but they are not the same power input.

[0048] It should be understood that "connection" in the following embodiments, if the circuits, modules, units and the like connected to each other have the transmission of electrical signals or data, it should be understood as "electrically connected", "communicatively connected" and the like.

[0049] As used herein, the singular forms "a", "an" and "the" can include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "comprise / comprising" or "have / having" specifies the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but does not exclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

[0050] Reference will now be made to Figure 1The application provides a temperature calibration structure 1, and an equivalent circuit of the temperature calibration structure 1 comprises a first bipolar transistor Q1, a second bipolar transistor Q2, a first resistor R1, a second resistor R2 and a third resistor R3; wherein the base of the first bipolar transistor Q1, the collector of the first bipolar transistor Q1, the base of the second bipolar transistor Q2 and the collector of the second bipolar transistor Q2 are all grounded; the first resistor R1 and the second resistor R2 are connected in series, and one end of the first resistor R1 away from the second resistor R2 is connected with the emitter of the first bipolar transistor Q1; one end of the third resistor R3 is connected with the emitter of the second bipolar transistor Q2, and the other end is connected with one end of the second resistor R2 away from the first resistor R1.

[0051] The temperature calibration structure 1 has the advantages that: the first bipolar transistor Q1 and the second bipolar transistor Q2 are arranged in the calibration structure 1, the bipolar transistor has high sensitivity to temperature, and the two bipolar transistors can further amplify the temperature trend, thereby improving the accuracy of temperature calibration, and the accuracy of temperature calibration can be less than 0.01 DEG C; meanwhile, the first resistor R1, the second resistor R2 and the third resistor R3 are arranged, and the accuracy of the temperature calibration structure 1 can be adjusted by adjusting the resistance values of the three resistors.

[0052] In one example, the second bipolar transistor Q2 is composed of N first bipolar transistors Q1 connected in parallel, wherein N is greater than 1; in this way, when the same voltage is applied to the emitter of the first bipolar transistor Q1 and the emitter of the second bipolar transistor Q2, the current of the emitter of the second bipolar transistor Q2 is N times the current of the emitter of the first bipolar transistor Q1, that is, the conduction current of the second bipolar transistor is N times the conduction current of the first bipolar transistor.

[0053] Specifically, the value range of N can be 5 <= N <= 15, and more specifically, N can be 5, 8, 10, 12, 15 and the like.

[0054] Specifically, taking N equal to 10 as an example, the characteristic of the emitter junction voltage VBE of a single bipolar transistor to temperature is about -2.2 mV / DEG C, and the characteristic of the emitter junction voltage difference AVBE of the first bipolar transistor Q1 and the second bipolar transistor Q2 in the temperature calibration structure 1 of the application to temperature is about 0.2 mV / DEG C, so it can be known that the temperature calibration structure 1 in the application has higher accuracy compared with the temperature calibration structure of a single bipolar transistor.

[0055] As an example, the first resistor R1, the second resistor R2 and the third resistor R3 can all be temperature-insensitive resistors, so as to avoid the influence of temperature on the resistance values of the first resistor R1, the second resistor R2 and the third resistor R3, thereby further ensuring the accuracy of the temperature calibration structure 1.

[0056] As an example, the resistance of the first resistor R1, the resistance of the second resistor R2 and the resistance of the third resistor R3 can be set according to actual needs. In the present embodiment, the resistance of the second resistor R2 is equal to the resistance of the third resistor R3, and is greater than the resistance of the first resistor R1.

[0057] In one example, the resistance of the second resistor R2 and the resistance of the third resistor R3 are both M times the resistance of the first resistor R1, where M is greater than 1.

[0058] Specifically, the value range of M is: 5≤M≤30, and more specifically, M can be 5, 10, 15, 20, 25 or 30, etc.

[0059] As an example, the first bipolar transistor Q1 and the second bipolar transistor Q2 can be the same type of bipolar transistor. In one example, the first bipolar transistor Q1 and the second bipolar transistor Q2 can both be PNP bipolar transistors; in another example, the first bipolar transistor Q1 and the second bipolar transistor Q2 can both be NPN bipolar transistors. Whether it is a PNP bipolar transistor or an NPN bipolar transistor, its specific structure is known to those skilled in the art, which will not be repeated here.

[0060] In an alternative embodiment, please continue to refer to Figure 1 The equivalent circuit of the temperature calibration structure 1 can further include an operational amplifier 11, which includes a positive input terminal, a negative input terminal and an output terminal. The positive input terminal of the operational amplifier 11 is connected between the third resistor R3 and the emitter of the second bipolar transistor Q2, the negative input terminal of the operational amplifier 11 is connected between the first resistor R1 and the second resistor R2, and the output terminal of the operational amplifier 11 is connected to the end of the third resistor R3 away from the second bipolar transistor Q2 and the end of the second resistor R2 away from the first resistor R1.

[0061] As an example, the temperature calibration structure 1 can be connected to multiple ports, each port being connected to a different test pad (PAD), such as Figure 1As shown, the temperature calibration structure 1 can have ports A, B, C and D, wherein the port A is a connection node of the output terminal of the operational amplifier 11, one end of the third resistor R3 away from the second bipolar transistor Q2, and one end of the second resistor R2 away from the first resistor R1, the port B is a connection node between the negative input terminal of the operational amplifier 11 and the first resistor R1 and the second resistor R2, the port C is a connection node between the positive input terminal of the operational amplifier 11 and the third resistor R3 and the emitter of the second bipolar transistor Q2, and the port D is a ground node of the collector of the first bipolar transistor Q1 and the collector of the second bipolar transistor Q2.

[0062] As an example, the temperature calibration structure 1 can be formed in a scribe lane of a wafer, so that the temperature calibration structure 1 can be formed in a normal chip process and does not occupy the effective area of the wafer for forming chips.

[0063] Please refer to Figure 1 Please refer to Figure 2 The present application also provides a temperature calibration system for calibrating a semiconductor machine, which comprises: a plurality of temperature calibration structures 1 according to any one of the above-mentioned embodiments, wherein the plurality of temperature calibration structures 1 are respectively located at different positions of a test area of the semiconductor machine (for example, different positions of a chuck for absorbing a wafer, i.e., the test area of the semiconductor machine can be the chuck for absorbing the wafer); a measuring device 2 for measuring the temperature calibration structures 1 to obtain a first volt-ampere characteristic curve between a first voltage and a current of the emitter of the first bipolar transistor Q1, and a second volt-ampere characteristic curve between a second voltage and a current of the emitter of the second bipolar transistor Q2, wherein the first voltage is the sum of the voltage between the base and the emitter of the first bipolar transistor Q1 and the voltage across the first resistor R1, and the second voltage is the voltage between the base and the emitter of the second bipolar transistor Q2; and a processing module 3 connected to the measuring device 2, for obtaining the voltage difference between the first voltage and the second voltage under the same emitter current condition and the change of the temperature with the voltage difference between the first voltage and the second voltage based on the linear regions of the first volt-ampere characteristic curve and the second volt-ampere characteristic curve, and obtaining the temperature of the position of each temperature calibration structure 1 based on the change of the temperature with the voltage difference between the first voltage and the second voltage.

[0064] As an example, the plurality of temperature calibration structures 1 are arranged in an array on the surface of the test area of the semiconductor machine, the array is centrally symmetrically distributed with respect to the center of the test area of the semiconductor machine, and at least one temperature calibration structure 1 is located at the center of the test area of the semiconductor machine.

[0065] In one example, as Figure 3As shown, five temperature calibration structures 1 can be arranged in an array on the surface of the chuck 4 used to support the wafer. One of the temperature calibration structures 1 is located at the center of the chuck 4, and the other four temperature calibration structures 1 are symmetrically distributed on the left and right sides and the top and bottom sides of the temperature calibration structure 1 located at the center of the chuck 4, and there is a gap between each temperature calibration structure 1.

[0066] In another example, such as Figure 4 As shown, nine temperature calibration structures 1 can be placed on the surface of the suction cup 4 to form an array. The nine temperature calibration structures 1 in the array are arranged in a three-row, three-column array, and the temperature calibration structure 1 located at the intersection of the second row and the second column is located at the center of the suction cup 4.

[0067] It should be noted that, Figure 3 and Figure 4 These are just two examples of array layouts. In other examples, the specific number and arrangement of the temperature calibration structures 1 in the array can be set according to actual needs, and are not required to be specific to these examples. Figure 3 and Figure 4 The examples shown are for reference only.

[0068] As an example, the measuring device 2 places probes on the test pads connected to each port respectively, and the first and second current-voltage characteristic curves can be obtained by measuring the probes. Taking the first bipolar transistor Q1 and the second bipolar transistor Q2 as examples where both are PNP bipolar transistors, the first current-voltage characteristic curve under a certain temperature condition is as follows: Figure 5 As shown in curve ①, the second current-voltage characteristic curve is as follows: Figure 5 As shown in curve ②, the first and second volt-ampere characteristic curves are significantly affected by temperature; different first and second volt-ampere characteristic curves will be obtained under different temperature conditions.

[0069] It should be noted that, by Figure 5 It can be seen that when both the first bipolar transistor Q1 and the second bipolar transistor Q2 are NPN bipolar transistors, the values ​​of the first voltage and the second voltage will be between 0.5 and 1.2V. When both the first bipolar transistor Q1 and the second bipolar transistor Q2 are PNP bipolar transistors, the values ​​of the first voltage and the second voltage will be between -1.2 and -0.5V.

[0070] As an example, the processing module 3 obtains the linear relationship between the voltage difference between the first voltage and the second voltage and the temperature under the same emitter current condition based on the linear region of the first current-voltage characteristic curve and the linear region of the second current-voltage characteristic curve, and obtains the temperature of each temperature calibration structure 1 based on the linear relationship.

[0071] Specifically, first, the voltage difference between the first voltage and the second voltage under a certain emitter current condition (for example, the emitter current is 1.0E-06A) can be obtained by intercepting the linear region of the first volt-ampere characteristic curve and the second volt-ampere characteristic curve in Figure 5 ; then the temperature is transformed to obtain the first volt-ampere characteristic curve and the second volt-ampere characteristic curve corresponding to the temperature condition, and the voltage difference between the first voltage and the second voltage corresponding to the temperature under the same emitter current condition is intercepted; by transforming the temperature, the voltage difference between the first voltage and the second voltage at different temperatures can be obtained; according to the corresponding relationship between the obtained voltage difference between the first voltage and the second voltage and the temperature, the linear relationship of the voltage difference between the first voltage and the second voltage with the temperature change can be obtained.

[0072] As an example, the linear relationship of the voltage difference between the first voltage and the second voltage with the temperature change can be a linear function relationship as shown in Figure 6 , and the formula of the linear function relationship can be:

[0073] y=kx+b

[0074] wherein y is the voltage difference between the first voltage and the second voltage, k is the slope of the linear relationship, x is the temperature at the position of the temperature calibration structure 1, and b is the intercept of the linear relationship. Since k and b are constants obtained according to the corresponding relationship between the obtained voltage difference between the first voltage and the second voltage and the temperature, and the voltage difference y between the first voltage and the second voltage can be obtained according to the measurement result of the measurement device 2, according to the above formula, the temperature x at the position of the temperature calibration structure 1 can be obtained.

[0075] Please refer to Figure 6 , Figure 6 When the resistance value of the second resistance R2 and the resistance value of the third resistance R3 are equal in the temperature calibration structure of the present application, the linear relationship of the voltage difference between the first voltage and the second voltage with the temperature change corresponding to the different resistance value ratio of the resistance value of the second resistance R2 and the resistance value of the third resistance R3 to the resistance value of the first resistance R1; wherein, Figure 6 the curve ① in is the linear relationship of the voltage difference between the first voltage and the second voltage with the temperature change when the resistance value ratio of the resistance value of the second resistance R2 and the resistance value of the third resistance R3 to the resistance value of the first resistance R1 is 1, Figure 6 the curve ② in is the linear relationship of the voltage difference between the first voltage and the second voltage with the temperature change when the resistance value ratio of the resistance value of the second resistance R2 and the resistance value of the third resistance R3 to the resistance value of the first resistance R1 is 10, Figure 6 the curve ③ in is the linear relationship of the voltage difference between the first voltage and the second voltage with the temperature change when the resistance value ratio of the resistance value of the second resistance R2 and the resistance value of the third resistance R3 to the resistance value of the first resistance R1 is 20. From Figure 6It can be known that the linear relationship formula of the curve ① is y = 1.95E-04x + 5.46E-02, that is, the slope of the linear relationship of the curve ① is 1.95E-04, and the intercept is 5.46E-02; the linear relationship formula of the curve ② is y = 1.95E-03x + 5.46E-01, that is, the slope of the linear relationship of the curve ② is 1.95E-03, and the intercept is 5.46E-01; the linear relationship formula of the curve ③ is y = 3.91E-03x + 1.09E+00, that is, the slope of the linear relationship of the curve ③ is 3.91E-03, and the intercept is 1.09E+00. This shows that with the increase of the resistance value ratio of the resistance value of the second resistor R2 and the resistance value of the third resistor R3 to the resistance value of the first resistor R1, the amplification effect of the temperature calibration structure 1 on the temperature is more and more large, and the precision of the temperature calibration is higher.

[0076] Please combine Figures 1-6 Please combine Figure 7 The application also provides a temperature calibration method, the temperature calibration method comprising:

[0077] S10: Placing a plurality of temperature calibration structures 1 as described in any of the above solutions at different positions of a semiconductor machine test area;

[0078] S20: Measuring the temperature calibration structure 1 to obtain a first volt-ampere characteristic curve between a first voltage and a current of an emitter of a first bipolar transistor Q1 and a second volt-ampere characteristic curve between a second voltage and a current of an emitter of a second bipolar transistor Q2; wherein the first voltage is the sum of the voltage between the base and the emitter of the first bipolar transistor Q1 and the voltage across the first resistor R1, and the second voltage is the voltage between the base and the emitter of the second bipolar transistor Q2;

[0079] S30: Obtaining the change of the voltage difference between the first voltage and the second voltage with temperature under the same emitter current condition according to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve, and obtaining the temperature of the position of each temperature calibration structure 1 based on the change of the voltage difference between the first voltage and the second voltage with temperature.

[0080] As an example, in step S10, a plurality of temperature calibration structures 1 are arranged in an array on the surface of a chuck 4 for carrying a wafer, the array is centrally symmetrically distributed with the center of the semiconductor machine test area, and at least one temperature calibration structure 1 is located at the center of the semiconductor machine test area. In one example, five temperature calibration structures 1 can be arranged in an array on the surface of the chuck 4 as shown in Figure 3 In another example, nine temperature calibration structures 1 can be arranged in an array on the surface of the chuck 4 as shown in Figure 4

[0081] ​It should be noted that, Figure 3 and Figure 4 These are just two examples of array layouts. In other examples, the specific number and arrangement of the temperature calibration structures 1 in the array can be set according to actual needs, and are not required to be specific to these examples. Figure 3 and Figure 4 The examples shown are for reference only.

[0082] As an example, in step S20, Figure 2 The measuring device 2 can place probes on the test pads connected to each port respectively, and obtain the first and second current-voltage characteristic curves through the probes. Taking PNP bipolar transistors Q1 and Q2 as examples, the first current-voltage characteristic curve under a certain temperature condition is as follows: Figure 5 As shown in curve ①, the second current-voltage characteristic curve is as follows: Figure 5 As shown in curve ②, the first and second volt-ampere characteristic curves are significantly affected by temperature; different first and second volt-ampere characteristic curves will be obtained under different temperature conditions.

[0083] As an example, step S30 may include:

[0084] The processing module 3 obtains the linear relationship between the voltage difference between the first voltage and the second voltage and the temperature under the same emitter current condition based on the linear region of the first current-voltage characteristic curve and the linear region of the second current-voltage characteristic curve, and obtains the temperature of each temperature calibration structure 1 based on the linear relationship.

[0085] As an example, the linear relationship between the voltage difference between the first voltage and the second voltage and temperature is a linear function, as shown in the formula:

[0086] y = kx + b

[0087] Where y is the voltage difference between the first voltage and the second voltage, k is the slope of the linear relationship, x is the temperature at the location of temperature calibration structure 1, and b is the intercept of the linear relationship. Since k and b are constants that can be obtained from the correspondence between the voltage difference between the first voltage and the second voltage and the temperature, and the voltage difference y between the first voltage and the second voltage can be obtained from the measurement results of measuring device 2, the temperature x at the location of temperature calibration structure 1 can be obtained according to the above formula.

[0088] In the description of this specification, references to terms such as "one embodiment," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0089] The technical features of the above-described embodiments can be combined in any manner. For the sake of brevity, not all possible combinations of the technical features in the above-described embodiments are described. However, any combination of the technical features that does not result in a contradiction should be considered as within the scope of the present disclosure.

[0090] The above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but should not be understood as a limitation on the patent scope of the present application. It should be noted that, for those skilled in the art, some modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A temperature calibration structure, characterized in that, an equivalent circuit of the temperature calibration structure comprises a first bipolar transistor, a second bipolar transistor, a first resistor, a second resistor and a third resistor, wherein, a base of the first bipolar transistor, a collector of the first bipolar transistor, a base of the second bipolar transistor and a collector of the second bipolar transistor are all grounded; the first resistor and the second resistor are connected in series, and one end of the first resistor away from the second resistor is connected to an emitter of the first bipolar transistor; one end of the third resistor is connected to an emitter of the second bipolar transistor, and the other end of the third resistor is connected to one end of the second resistor away from the first resistor; a resistance value of the second resistor is equal to a resistance value of the third resistor, and both of the resistance values are M times of a resistance value of the first resistor; and the first resistor is an adjustable resistor. 2.The temperature calibration structure according to claim 1, characterized in that, a conduction current of the second bipolar transistor is N times of a conduction current of the first bipolar transistor, wherein N is greater than 1. 3.The temperature calibration structure according to claim 2, characterized in that, a value of N is in a range of 5≤N≤15. 4.The temperature calibration structure according to claim 1, characterized in that, the resistance value of the second resistor and the resistance value of the third resistor are greater than the resistance value of the first resistor. 5.The temperature calibration structure according to claim 1, characterized in that, M is greater than 1. 6.The temperature calibration structure according to claim 5, characterized in that, a value of M is in a range of 5≤M≤30. 7.The temperature calibration structure according to claim 1, characterized in that, the first bipolar transistor and the second bipolar transistor both comprise a PNP bipolar transistor or both comprise an NPN bipolar transistor. 8.The temperature calibration structure according to any one of claims 1 to 7, characterized in that, the equivalent circuit of the temperature calibration structure further comprises an operational amplifier, the operational amplifier comprises a positive input end, a negative input end and an output end, the positive input end of the operational amplifier is connected between the third resistor and the emitter of the second bipolar transistor, the negative input end of the operational amplifier is connected between the first resistor and the second resistor, and the output end of the operational amplifier is connected to one end of the third resistor away from the second bipolar transistor and one end of the second resistor away from the first resistor. 9.A temperature calibration system, characterized in that, for calibrating a temperature of a semiconductor machine, the temperature calibration system comprises: a plurality of temperature calibration structures according to any one of claims 1 to 8, the plurality of temperature calibration structures are respectively located at different positions of a test area of the semiconductor machine. a measuring device configured to measure the temperature calibration structure to obtain a first volt-ampere characteristic curve between a first voltage and a current of an emitter of the first bipolar transistor, and a second volt-ampere characteristic curve between a second voltage and the current of the emitter of the second bipolar transistor; wherein the first voltage is a sum of a voltage between a base and the emitter of the first bipolar transistor and a voltage across the first resistor, and the second voltage is a voltage between a base and the emitter of the second bipolar transistor; a processing module connected to the measuring device, configured to obtain a voltage difference between the first voltage and the second voltage varying with temperature under a same emitter current condition according to a linear region of the first volt-ampere characteristic curve and a linear region of the second volt-ampere characteristic curve, and obtain a temperature of a position where each temperature calibration structure is located based on the voltage difference between the first voltage and the second voltage varying with temperature. The equivalent circuit of the temperature calibration structure comprises a first resistor, a second resistor and a third resistor, the first resistor and the second resistor are connected in series, one end of the third resistor is connected to the emitter of the second bipolar transistor, and the other end of the third resistor is connected to one end of the second resistor away from the first resistor, the resistance value of the second resistor is equal to the resistance value of the third resistor, and both are M times of the resistance value of the first resistor; the first resistor is an adjustable resistor.

10. The temperature calibration system of claim 9, wherein the processing module obtains a linear relationship of the voltage difference between the first voltage and the second voltage varying with temperature under the same emitter current condition according to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve, and obtains the temperature of the position where each temperature calibration structure is located based on the linear relationship.

11. The temperature calibration system of claim 9 or 10, wherein a plurality of the temperature calibration structures form an arrangement array on a surface of the semiconductor machine test area, the arrangement array is centrally symmetrically distributed with a center of the semiconductor machine test area, and at least one of the temperature calibration structures is located at the center of the semiconductor machine test area.

12. A temperature calibration method, comprising: placing a plurality of temperature calibration structures according to any one of claims 1 to 8 at different positions of a semiconductor machine test area; measuring the temperature calibration structure to obtain a first volt-ampere characteristic curve between a first voltage and a current of an emitter of the first bipolar transistor, and a second volt-ampere characteristic curve between a second voltage and the current of the emitter of the second bipolar transistor; wherein the first voltage is a sum of a voltage between a base and the emitter of the first bipolar transistor and a voltage across the first resistor, and the second voltage is a voltage between a base and the emitter of the second bipolar transistor; ​ According to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve, the voltage difference between the first voltage and the second voltage changes with temperature under the same emitter current condition, and the temperature at the position of each temperature calibration structure is obtained based on the voltage difference between the first voltage and the second voltage changing with temperature. The equivalent circuit of the temperature calibration structure comprises a first resistor, a second resistor and a third resistor, the first resistor and the second resistor are connected in series, one end of the third resistor is connected to the emitter of the second bipolar transistor, and the other end is connected to the end of the second resistor away from the first resistor, the resistance value of the second resistor is equal to the resistance value of the third resistor, and both are M times the resistance value of the first resistor; the first resistor is an adjustable resistor.

13. The temperature calibration method of claim 12, wherein, the temperature at the position of each temperature calibration structure is obtained based on the voltage difference between the first voltage and the second voltage changing with temperature according to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve under the same emitter current condition comprises: the processing module obtains a linear relationship between the voltage difference between the first voltage and the second voltage and temperature under the same emitter current condition according to the linear region of the first volt-ampere characteristic curve and the linear region of the second volt-ampere characteristic curve, and obtains the temperature at the position of each temperature calibration structure based on the linear relationship.

14. The temperature calibration method of claim 13, wherein, the linear relationship is a first-order function relationship, and the formula is: y=kx+b wherein y is the voltage difference between the first voltage and the second voltage, k is the slope of the linear relationship, x is the temperature at the position of the temperature calibration structure, and b is the intercept of the linear relationship.

15. The temperature calibration method of any one of claims 12-14, wherein, after placing a plurality of temperature calibration structures at different positions of a semiconductor machine test area, the plurality of temperature calibration structures form an arrangement array on the surface of the semiconductor machine test area, the arrangement array is centrally symmetrically distributed with the center of the semiconductor machine test area as the center, and at least one temperature calibration structure is located at the center of the semiconductor machine test area.

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