Detection system for thermoelectric film performance

Abstract

This application discloses a system for testing the performance of thermoelectric thin films. This application relates to the technical field of thermoelectric thin film material testing technology and addresses the existing inability to perform voltage testing on thermoelectric thin film samples fabricated on insulating substrates, as well as the inability to test the voltage of smaller thermoelectric films. The testing system includes a sample stage, which includes an insulating thermally conductive substrate with pyroelectric properties for placement of the thermoelectric thin film sample. This application utilizes an insulating thermally conductive substrate with pyroelectric properties to place the thermoelectric thin film sample. During voltage testing of the thermoelectric thin film sample, the insulating thermally conductive substrate with pyroelectric properties can amplify the voltage of the thermoelectric thin film sample, thereby enabling voltage testing of small thermoelectric thin film samples and those mounted on insulating conductive substrates.

Description

Technical Field

[0001] The present application relates to the technical field of thermoelectric thin film material testing, and in particular to a detection system for thermoelectric thin film performance. Background Art

[0002] Thermoelectric materials convert heat into electricity through the thermoelectric effect, which primarily includes the Seebeck effect, the Peltier effect, and the Thomson effect. The Seebeck effect is a key research area, directly converting heat into electricity. Specifically, it generates an electric potential difference between two ends of an object with a temperature difference. To achieve high electrical-to-heat conversion, thermoelectric materials must possess high electrical conductivity and a high Seebeck coefficient, while also exhibiting low thermal conductivity. Rapid economic development has placed high demands on thermoelectric materials, making the development of high-performance thermoelectrics a research hotspot. Traditional thermoelectric material development techniques, based on a "prepare-test-improve-prepare" approach, are time-consuming and have limited the development and application of new thermoelectric materials. In recent years, high-throughput material technologies based on artificial intelligence and machine learning have accelerated the development of new materials. These technologies include high-throughput material preparation and rapid characterization of properties. High-throughput preparation is the first step in developing new materials, and the precision of sample preparation is crucial. Testing these high-throughput samples is essential for screening high-performance thermoelectric materials.

[0003] Currently, the performance test of thermoelectric thin film samples mainly relies on commercial conductivity-Seebeck coefficient scanning probes. In practical applications, this method has the following shortcomings: some existing thermoelectric thin film samples need to be prepared on a conductive substrate, and some need to be prepared on an insulating substrate. Since the voltage of the thermoelectric thin film samples prepared on the insulating substrate is too small, this method can only perform voltage tests on thermoelectric thin film samples prepared on a conductive substrate, but cannot perform voltage tests on thermoelectric thin film samples prepared on an insulating substrate. This method cannot test thermoelectric films of smaller sizes.

[0004] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0005] The technical problem to be solved by this application is to provide a thermoelectric film performance detection system in response to the shortcomings of the existing technology, so as to solve the existing problems of being unable to perform voltage testing on thermoelectric film samples prepared on an insulating substrate and being unable to test the voltage of smaller thermoelectric films.

[0006] The sample stage includes an insulating thermally conductive substrate with pyroelectric properties, which is used to place the thermoelectric film sample. When the thermoelectric film sample is subjected to a voltage test, the insulating thermally conductive substrate with pyroelectric properties is used to amplify the voltage of the thermoelectric film sample.

[0007] In one implementation, the detection system further includes:

[0008] a heat source monitoring device, the heat source monitoring device being disposed on the sample stage and being used to supply a non-uniform temperature field to the thermoelectric thin film sample;

[0009] A data acquisition device, wherein the data acquisition device is used to collect the voltage of the thermoelectric thin film sample;

[0010] A probe station, wherein the probe station is provided with a plurality of probe placement parts;

[0011] A plurality of probes, one end of each probe is arranged on the probe placement portion, and the other end is connected to the data acquisition device.

[0012] In one implementation, a spring is disposed in the probe.

[0013] In one implementation, the detection system further includes a translation stage, the sample stage is disposed on the translation stage, and the translation stage drives the sample stage to move horizontally.

[0014] In one implementation, a first temperature detection device is provided on the sample stage, and the first temperature detection device is used to detect the damage degree of the thermoelectric thin film sample.

[0015] In one implementation, the insulating thermally conductive substrate is one of barium titanate, lithium niobate, lithium tantalate, and lead titanate.

[0016] In one implementation, the heat source monitoring device includes:

[0017] A heating device, wherein the heating device is arranged on the sample stage;

[0018] a second temperature detection device, the second temperature detection device being disposed on the heating device;

[0019] A temperature control device is connected to the heating device.

[0020] In one implementation, when the heating device is a thermoelectric plate, the temperature control device is a DC power supply.

[0021] In one implementation, when the heating device is a laser, the temperature control device is a modulator.

[0022] In one implementation, the data acquisition device includes:

[0023] A data acquisition card having a plurality of data acquisition channels connected to the probes;

[0024] A host computer is connected to the data acquisition card and is used for data collection and analysis.

[0025] Beneficial effect: This embodiment adopts an insulating thermal conductive substrate with pyroelectric properties to place the thermoelectric thin film sample. When the thermoelectric thin film sample is subjected to voltage testing, the insulating thermal conductive substrate with pyroelectric properties can amplify the voltage of the thermoelectric thin film sample, thereby realizing voltage testing of the thermoelectric thin film sample with a small size and on the insulating conductive substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without inventive work.

[0027] Figure 1 This is a schematic diagram of the structure of the thermoelectric film performance detection system provided in this application.

[0028] Figure 2 This is a schematic structural diagram of a thermoelectric film sample to be tested in the thermoelectric film performance detection system provided in this application.

[0029] Figure 3 This is a schematic structural diagram of a thermoelectric film sample to be tested placed on a sample stage in the thermoelectric film performance detection system provided in this application.

[0030] Figure 4 This is a schematic diagram of the material composition distribution of the thermoelectric thin film sample on the sample stage in the thermoelectric thin film performance detection system provided in this application.

[0031] Figure 5 This is a schematic diagram of monitoring the operation of the heating device by the second temperature detection device in the thermoelectric film performance detection system provided in this application.

[0032] Figure 6 This is a voltage distribution diagram of thermoelectric film samples at various positions on some sample stages in the thermoelectric film performance detection system provided in this application.

[0033] In the figure: 01, thermoelectric thin film sample; 10, sample stage; 101, placement slot; 20, probe; 30, translation stage; 401, heating device; 402, second temperature detection device; 403, temperature control device; 501, data acquisition card; 502, host computer. DETAILED DESCRIPTION

[0034] This application provides a thermoelectric thin film performance detection system. To make the purpose, technical solution, and effects of this application more clear and explicit, the application is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific examples described here are only for the purpose of explaining this application and are not intended to limit this application.

[0035] It will be understood by those skilled in the art that, unless expressly stated otherwise, the singular forms "a", "an", "said" and "the" used herein may also include the plural forms. It should be further understood that the term "comprising" used in the specification of the present application refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. In addition, "connected" or "coupled" as used herein may include wireless connections or wireless couplings. The term "and / or" used herein includes all or any units and all combinations of one or more associated listed items.

[0036] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0037] The application content will be further explained below through description of embodiments in conjunction with the accompanying drawings.

[0038] If you choose to use the Seebeck effect to study the performance of thermoelectric materials, you should know that the Seebeck coefficient is an important coefficient that characterizes the performance of thermoelectric materials. A large Seebeck coefficient indicates that the thermoelectric material has good performance. The Seebeck effect is specifically manifested as an electric potential difference generated at the two ends of an object with a temperature difference. The Seebeck coefficient is proportional to the electromotive force and inversely proportional to the temperature difference. Currently, the performance test of thermoelectric materials mainly relies on commercial conductivity-Seebeck coefficient scanning probes. The thermoelectric materials that can be tested need to have a certain thickness, so that the thermoelectric materials have a certain temperature difference and thus generate a testable potential difference. This application cannot test smaller thermoelectric films. In addition, since the voltage of the thermoelectric material prepared on the insulating substrate is too small, this application cannot test the thermoelectric material prepared on the insulating substrate.

[0039] like Figure 1-3As shown, this embodiment provides a detection system for the performance of thermoelectric thin films, the detection system includes a sample stage 10, the sample stage 10 includes an insulating thermal conductive substrate with pyroelectric properties, the sample stage 10 is provided with a placement groove 101, and the thermoelectric thin film samples 01 are arranged on the placement groove 101 in a matrix manner. In this embodiment, the thermoelectric thin film samples 01 are placed on the insulating thermal conductive substrate with pyroelectric properties. When the thermoelectric thin film samples 01 are subjected to a voltage test, the insulating thermal conductive substrate with pyroelectric properties can amplify the voltage of the thermoelectric thin film samples 01, thereby realizing voltage testing of the thermoelectric thin film samples 01 that are small in size and on the insulating conductive substrate.

[0040] In one embodiment, depending on the test temperature, the insulating thermally conductive substrate may be one of barium titanate, lithium niobate, lithium tantalate, and lead titanate. Of course, this embodiment is not limited to the above.

[0041] like Figure 1 As shown, in one embodiment, the detection system further includes a heat source monitoring device and a data acquisition device. The heat source monitoring device is arranged on the sample stage 10, and the heat source monitoring device is used to provide a non-uniform temperature field for the thermoelectric film sample 01, so that the thermoelectric film sample 01 on the sample stage 10 can generate a temperature difference and thus generate an electromotive force (voltage); the data acquisition device is used to collect the voltage generated by the temperature difference of the thermoelectric film sample 01. Compared with the traditional detection method of a single probe 20, this embodiment is provided with a probe stage and a plurality of probes 20, and a plurality of probe 20 placement parts are provided on the probe stage. One end of the probe 20 is arranged on the probe 20 placement portion (not shown in the figure), and the other end is connected to the data acquisition device. That is to say, by setting up a probe station, the probe station can accommodate several probes 20 at the same time. Correspondingly, the sample stage 10 also accommodates several thermoelectric film samples 01. The thermoelectric film samples 01 on the sample stage 10 belong to different components. Among them, the preparation of the thermoelectric film sample 01 used in this embodiment is based on magnesium, bismuth and tin as main components, and titanium, copper and the like as doping elements. High-flux thermoelectric films with different components are prepared on a substrate using electron beam evaporation combined with a mask, such as Figure 4 As shown, when in use, the probes 20 on the probe station are simultaneously inserted into the corresponding thermoelectric film samples 01 on the sample stage 10, and the data acquisition device collects and measures the voltage of the thermoelectric film sample 01 on the sample stage 10 through the probes 20, thereby realizing rapid screening of the thermoelectric film sample 01. Through the setting of the probe station, higher test efficiency is achieved.

[0042] like Figure 1As shown, optionally, the number of probes 20 of the probe station can be equal to the number of thermoelectric film samples 01 on the sample stage 10, and the number of probes 20 of the probe station can be less than the number of thermoelectric film samples 01 on the sample stage 10. In order to improve the applicability between the sample stage 10 and the probe station, this embodiment selects that the number of probes 20 of the probe station can be less than the number of thermoelectric film samples 01 on the sample stage 10. It can be understood that the area of ​​the probe station will be smaller than the area of ​​the sample stage 10. Then, in this case, the spacing between the probes 20 on the probe station can be equal to the spacing between the thermoelectric film samples 01 on the sample stage 10, and the spacing between the probes 20 on the probe station can be equal to the spacing between the thermoelectric film samples 01 on the sample stage 10. The spacing between them may also not be equal to the spacing between the thermoelectric film samples 01 on the sample stage 10. When the spacing between the probes 20 on the probe stage is not equal to the spacing between the thermoelectric film samples 01 on the sample stage 10, the probes 20 on the probe stage can be set to have an adjustable spacing, so that they can not only adapt to the current tested sample stage 10 through adjustment, but also adapt to other models of sample stages 10, thereby improving the applicability of the probe stage, wherein the spacing adjustment range between the probes 20 on the probe stage is 1-5mm; the diameter of the probe 20 is 0.2-2mm; the length of the probe 20 is 15-20mm; the needle tip of the probe 20 is round or square.

[0043] like Figure 1 As shown, in one embodiment, when the number of probes 20 of the selected probe station is less than the number of thermoelectric thin film samples 01 on the sample stage 10, that is, when the area of ​​the probe station is smaller than the area of ​​the sample stage 10, the detection system further includes a displacement stage 30, the displacement stage 30 is arranged on the test table, the sample stage 10 is arranged on the displacement stage 30, the displacement stage 30 can drive the sample stage 10 to move horizontally, and the probe station can move vertically, so that the data acquisition device collects and analyzes a part of the thermoelectric thin film samples 01 on the sample stage 10 through the probe 20 of the probe station. 1, the probe stage can be first moved up, and then the sample stage 10 is moved horizontally to the position of the probe stage corresponding to the untested thermoelectric thin film sample 01 on the sample stage 10 under the drive of the displacement stage 30, and the probe stage is moved down so that the probe 20 on the probe stage can be inserted into the corresponding thermoelectric thin film sample 01 to continue testing the untested thermoelectric thin film sample 01. The displacement stage 30 only needs to satisfy the function of driving the sample to move horizontally and does not need other functions. Since the displacement stage 30 is a prior art, the specific structure of the displacement stage 30 will not be elaborated in detail.

[0044] Furthermore, a spring (not shown in the figure) is provided in the probe 20 , and the contact force between the probe 20 and the thermoelectric thin film sample 01 can be adjusted by the provision of the spring.

[0045] In one embodiment, a first temperature detection device (not shown in the figure) is provided on the sample stage 10. The first temperature detection device is used to detect the degree of damage of the thermoelectric film sample 01. When the first temperature detection device detects that the temperature difference of the thermoelectric film sample 01 on the sample stage 10 is too large, it is determined that the thermoelectric film sample 01 is a damaged sample. The first temperature detection device can be used to exclude some damaged samples, thereby reducing useless data measurement and calculation. The first temperature detection device is an infrared camera.

[0046] like Figure 1 As shown, in one embodiment, the heat source monitoring device includes a heating device 401, a second temperature detection device 402 and a temperature control device 403. The heating device 401 is arranged on the displacement stage 30. It can be understood that the heating device 401 is arranged on the sample stage 10 through the displacement stage 30, and the second temperature detection device 402 is arranged on the heating device 401. The temperature control device 403 is connected to the heating device 401 and controls the heating of the heating device 401; wherein, the heating device 401 can be a thermoelectric plate or a laser, etc., the temperature control device 403 can be a DC power supply or a modulator, etc., and the second temperature detection device 402 can be a thermocouple, etc. In specific use, this embodiment Different heating devices 401 and temperature control devices 403 will be selected according to the size of the thermoelectric film sample 01 and the test frequency. For the thermoelectric film sample 01 with a low temperature change frequency during the test, a thermoelectric sheet will be used for heating; and for the thermoelectric film sample 01 with a high temperature change frequency during the test, a laser will be used for heating, and the frequency of the laser includes but is not limited to 808nm, 915nm, and 940nm; when heating with a thermoelectric sheet, a DC power supply will be used for control, and the temperature of the thermoelectric sheet will be changed by changing the output current of the DC power supply; and when heating with a laser, a modulator will be used for control, and the temperature will be controlled by changing the output power of the laser through the modulator, and a thermocouple will be used to monitor the temperature field of the thermoelectric film sample 01; Figure 5 As shown in the figure, when the probes 20 of the probe station are respectively inserted into the thermoelectric thin film sample 01 on the sample stage 10, and then the heating device 401 is used to heat the thermoelectric thin film sample 01 on the sample stage 10 in the form of evenly spaced time periods, the heating curve is formed.

[0047] like Figure 1As shown, in one embodiment, the data acquisition device includes a data acquisition card 501 and a host computer 502. The data acquisition card 501 has several data acquisition channels, and the data acquisition channels are connected to the probe 20; the host computer 502 is connected to the data acquisition card 501, and the host computer 502 can be a control terminal such as a computer. The host computer 502 is installed with data acquisition software. When the data acquisition software collects the voltage of each thermoelectric film sample 01 under the action of the data acquisition card 501 and the probe 20, it is uploaded to the host computer 502 for data collection and analysis. Figure 6 As shown, the figure is a voltage data diagram of the thermoelectric film sample 01 at various positions on the sample stage 10, wherein different colors in the figure mark the magnitude of different voltages; the data acquisition card 501 can be but is not limited to the NI USB-6211 data acquisition card 501779676-01, etc.

[0048] In one embodiment, a sample fixing fixture (not shown in the figure) is provided on the sample stage 10, and the sample fixing fixture is used to fix the thermoelectric film sample 01 to prevent the probe 20 from being offset when inserted into the corresponding thermoelectric film sample 01 during the test of the thermoelectric film sample 01. This setting avoids affecting the accuracy of the voltage test of the thermoelectric film sample 01. It is worth noting that as long as the sample fixing fixture can achieve the function of fixing the thermoelectric film sample 01, it is not limited to a specific structure.

[0049] The detection process of the thermoelectric film performance detection system is as follows: during the test, the thermoelectric film sample 01 is first placed in the placement slot 101 of the sample stage 10, and then the thermoelectric film sample 01 is fixed with a sample fixing fixture, and the probe 20 on the probe stage is brought into contact with the corresponding thermoelectric film sample 01. Then, the heat source monitoring device is controlled to provide a different test temperature for the thermoelectric film sample 01 and provide a periodic temperature field. The voltage values ​​of the thermoelectric film samples 01 of different compositions on the sample stage 10 are collected using a data acquisition device. This embodiment can measure the voltage at several different test positions of the thermoelectric film sample 01. Combined with the correlation between the thermoelectric voltage and the Seebeck coefficient, it can realize the screening of thermoelectric properties at different positions, realize the rapid characterization of high-throughput thermoelectric materials, and improve the research and development efficiency of thermoelectric materials.

[0050] In summary, this embodiment provides a detection system for the performance of thermoelectric thin films, which includes a sample stage 10, wherein the sample stage 10 includes an insulating thermally conductive substrate with pyroelectric properties. The sample stage 10 is provided with a placement groove 101, and the thermoelectric thin film samples 01 are arranged on the placement groove 101 in a matrix manner. This embodiment uses an insulating thermally conductive substrate with pyroelectric properties to place the thermoelectric thin film samples 01. When the thermoelectric thin film samples 01 are subjected to a voltage test, the insulating thermally conductive substrate with pyroelectric properties can amplify the voltage of the thermoelectric thin film samples 01, thereby realizing voltage testing of the thermoelectric thin film samples 01 that are small in size and on the insulating conductive substrate.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A thermoelectric film performance detection system, characterized in that: The detection system comprises: A sample stage, comprising an insulating thermally conductive substrate with pyroelectric properties, for placing a thermoelectric thin film sample. When performing a voltage test on the thermoelectric thin film sample, the insulating thermally conductive substrate with pyroelectric properties is used to amplify the voltage of the thermoelectric thin film sample, thereby enabling voltage testing of the thermoelectric thin film sample on the small insulating substrate; a heat source monitoring device, the heat source monitoring device being disposed on the sample stage and being used to supply a non-uniform temperature field to the thermoelectric thin film sample; A data acquisition device, wherein the data acquisition device is used to collect the voltage of the thermoelectric thin film sample; A probe station, wherein the probe station is provided with a plurality of probe placement parts; A plurality of probes, one end of each probe being disposed on the probe placement portion and the other end being connected to a data acquisition device; The insulating thermally conductive substrate is one of barium titanate, lithium niobate, lithium tantalate and lead titanate.

2. The thermoelectric film performance detection system according to claim 1, characterized in that: A spring is arranged in the probe.

3. The thermoelectric film performance detection system according to claim 1, characterized in that: The detection system further includes a displacement stage, the sample stage is arranged on the displacement stage, and the displacement stage drives the sample stage to move horizontally.

4. The thermoelectric film performance detection system according to claim 1, characterized in that: The sample stage is provided with a first temperature detection device, which is used to detect the damage degree of the thermoelectric thin film sample.

5. The thermoelectric film performance detection system according to claim 1, characterized in that: Heat source monitoring equipment includes: A heating device, wherein the heating device is arranged on the sample stage; a second temperature detection device, the second temperature detection device being disposed on the heating device; A temperature control device is connected to the heating device.

6. The thermoelectric film performance detection system according to claim 5, characterized in that: When the heating device is a thermoelectric plate, the temperature control device is a DC power supply.

7. The thermoelectric film performance detection system according to claim 5, characterized in that: When the heating device is a laser, the temperature control device is a modulator.

8. The thermoelectric film performance detection system according to claim 1, characterized in that: The data acquisition device includes: A data acquisition card having a plurality of data acquisition channels connected to the probes; A host computer is connected to the data acquisition card and is used for data collection and analysis.

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