High-voltage testing device and method for high-power power electronic chip

Abstract

The invention relates to a high-voltage testing device and method for a high-power power electronic chip. The device comprises a probe assembly, a probe adjusting unit, a wafer positioning platform and a positioning platform movement unit. The wafer positioning platform is used for fixing a chip, and the positioning platform movement unit is used for bearing the chip in the wafer positioning platform to move in a plane range; the probe assembly is used for carrying out connection test on a chip, and the probe adjusting unit is used for controlling the relative position of the probe assembly and the wafer positioning platform; through the design of different specifications of the probe assembly and the wafer positioning platform, high-voltage testing can be carried out on chips of different voltage grades, the distance between a probe and an oil pool can be flexibly adjusted in the testing process through the probe adjusting unit and the positioning platform moving unit, and the testing efficiency of the high-voltage power electronic chip is improved. The problems that the depth of an oil pool cannot be flexibly adjusted, the chip is ignited at high voltage and automatic testing is difficult due to limitation of the design size and specification of a probe in the chip testing process are solved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor chip testing technology, and in particular to a high-voltage testing device and method for high-power power electronic chips. Background Art

[0002] At present, high-power power electronic chips have become very important core components in power systems. These high-power power electronic chips and related modules play an important role in the conversion, control and transmission of electric energy, and are widely used in various power electronic equipment.

[0003] In recent years, as the performance of power chips continues to improve, the voltage level has gradually increased, and the power density has become higher and higher, which can achieve more efficient power conversion. Secondly, the vigorous rise of new materials has also promoted the development of the power electronics chip industry. For example, the use of third-generation wide-bandgap semiconductor materials such as silicon carbide and gallium nitride has significantly improved the performance of power chips under high voltage. At the same time, the investment in fourth-generation semiconductors such as gallium oxide and diamond has also attracted a lot of research.

[0004] However, the current development of high-power power electronic chips still faces problems such as high cost and low reliability. Due to the high cost and low yield rate of high-power power electronic chips, the cost of chip packaging and testing will be further increased, and the cause of chip failure is difficult to locate, which increases time cost and money investment. Therefore, it is particularly important to screen out qualified chips when high-power power electronic chips are in the wafer stage. At present, in the high-voltage testing link of chips, the main focus is on screening the low leakage capacity and extreme withstand voltage parameters of the chips under high voltage, so as to make full use of the chips. However, since the testing process is exposed to the atmospheric environment, even under clean room conditions, arc discharge and chip burnout are very likely to occur, which will further increase the chip mortality rate. In addition, the test tools cannot be shared for different chips, and the test equipment has poor versatility, resulting in high test costs and low test efficiency. Summary of the invention

[0005] In order to overcome the above-mentioned deficiencies of the prior art, the present application provides a high-voltage testing device and method for high-power power electronic chips, which specifically adopts the following technical solutions:

[0006] A high-voltage test device for high-power electronic chips, the device comprising a test host device, a high-voltage test source meter device, a microscopic imaging device, a probe assembly, a probe adjustment unit, a wafer positioning platform, a positioning platform motion unit and a fixed base;

[0007] The wafer positioning platform is used to fix the power electronic chip during the test phase. The wafer positioning platform is placed on the positioning platform motion unit. The positioning platform motion unit carries the chip in the wafer positioning platform to move within a plane. The positioning platform motion unit is installed at the bottom of the fixed base.

[0008] The probe assembly is used to perform connection test on the power electronic chip in the wafer positioning platform. The probe assembly is located above the wafer positioning platform, and the probe assembly is connected to the fixed base through a probe adjustment unit. The relative position of the probe assembly and the wafer positioning platform is controlled by the probe adjustment unit.

[0009] The microscopic imaging device and the high-voltage test source meter device are both arranged above the probe assembly, and the high-voltage test source meter device and the probe assembly are electrically connected, the microscopic imaging device is used to magnify and observe the power electronic chip, and the high-voltage test source meter device is used to apply an electrical signal to the power electronic chip and detect electrical characteristics;

[0010] The test host device is located above the probe assembly and is installed on the top of the fixed base. The test host device is electrically connected to the high-voltage test source meter device, the probe adjustment unit, and the positioning platform motion unit respectively. The test host device is used to control the test process and receive test data.

[0011] Optional: The wafer positioning platform includes an oil pool made of high-conductivity metal material and a vacuum adsorption chuck, a receiving cavity for placing the power electronic chip is provided in the middle of the oil pool, and at least one clamp structure is provided on the upper edge of the side wall of the receiving cavity, and the power electronic chip is pressed tightly against the bottom of the receiving cavity through the clamp structure; the vacuum adsorption chuck is fixedly connected to the positioning platform motion unit, and a plurality of through holes are provided on the surface of the vacuum adsorption chuck, and a vacuum pipeline connecting the through holes is provided under the vacuum adsorption chuck.

[0012] Optionally: a positioning through hole is provided on the side of the vacuum adsorption chuck, a connector that cooperates with the vacuum adsorption chuck is provided at the bottom of the oil pool, and a positioning bolt that cooperates with the positioning through hole is provided on the connector, and the oil pool is fixed to the vacuum adsorption chuck through the positioning bolt and the positioning through hole.

[0013] Optionally: at least one thin groove is provided at the bottom of the oil pool, and the groove is used to assist the power electronic chip to separate from the bottom of the oil pool.

[0014] Optionally: the depth of the accommodating cavity of the oil pool is adapted according to the test voltage level of the power electronic chip, and the higher the test voltage level of the power electronic chip, the deeper the depth of the accommodating cavity.

[0015] Optionally: the probe adjustment unit includes a probe support platform and a height adjustment unit, and the probe support platform is adjusted in height in the up and down directions through the height adjustment unit; the upper surface of the probe support platform is provided with a magnetic metal layer, and the lower surface of the probe support platform is provided with an insulating layer made of a high dielectric constant insulating medium material; the height adjustment unit adopts a mechanical positioning slot or an automatic lifting method.

[0016] Optionally: the probe assembly includes a test probe and a needle holder, the needle holder is fixed to the probe support platform by magnetic attraction, and the needle holder is provided with a cable for transmitting electrical signals; the test probe is fixed on the needle holder, and the test probe is electrically connected to the cable on the needle holder.

[0017] Optionally, the curvature radius of the tip of the test probe is smaller than the minimum electrode area of ​​the power electronic chip.

[0018] Optionally: A honeycomb vibration isolation structure is provided at the bottom of the fixed base, and the honeycomb vibration isolation structure is used to eliminate the vibration influence of the outside world on the test process.

[0019] In addition, the present application also discloses a high-voltage test method for a high-power power electronic chip, the method is applied to the high-voltage test device for a high-power power electronic chip as described above, and the method comprises the following steps:

[0020] Before testing, the probe adjustment unit is raised and the wafer positioning platform is fixed on the positioning platform motion unit;

[0021] Place the power electronic chip into the oil pool of the wafer positioning platform and lower the probe adjustment unit to a preset height;

[0022] Select a probe assembly that matches the oil pool and install it on the probe adjustment unit, and level the wafer positioning platform;

[0023] Inject a preset height of an isolation dielectric into the oil pool of the wafer positioning platform, connect the probe assembly to the high-voltage test source meter device, and set test parameters for the high-voltage test source meter device;

[0024] The probe assembly performs connection tests on the power electronic chips in the wafer positioning platform in sequence according to a preset test sequence;

[0025] After each test of an area of ​​the power electronic chip is completed, the probe assembly is raised and the test data is saved; then the next area of ​​the power electronic chip is replaced and the test is continued until all areas of the power electronic chip are tested;

[0026] After all areas of the power electronic chip are tested, the probe adjustment unit is raised, the oil pool is removed, the next power electronic chip is replaced and the test continues.

[0027] Beneficial Effects

[0028] The technical solution of this application has the following beneficial effects:

[0029] The present application is used for a high-power power electronic chip high-voltage test device to solve the current high-voltage chip testing process, which is limited by the design size and specifications of the probe platform, resulting in the inability to flexibly adjust the oil pool depth, causing high-voltage sparking of the chip and difficulty in automated testing. Through the different specification designs of the probe assembly and the wafer positioning platform, high-voltage testing can be performed on chips of different voltage levels, and the probe adjustment unit and the positioning platform motion unit can be used to flexibly adjust the distance between the probe and the oil pool during the test process, thereby improving the test efficiency of the high-voltage power electronic chip, and then qualified chips can be screened out at the wafer stage, preparing the chips for subsequent packaging and testing processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a structural diagram of a high-power power electronic chip high-voltage testing device using a mechanical clamping slot in an embodiment of the present application.

[0031] Figure 2 This is a structural diagram of a high-power power electronic chip high-voltage testing device that uses an automatic lifting method in an embodiment of the present application.

[0032] Figure 3 This is a structural diagram of the oil pool in the wafer positioning platform according to an embodiment of the present application.

[0033] The meanings of the reference numerals in the accompanying drawings are:

[0034] 1-fixed base; 2-test host device; 3-high voltage test source meter device; 4-microscope imaging device; 5-probe assembly; 6-probe adjustment unit; 601-probe support platform; 602-height adjustment unit; 7-wafer positioning platform; 71-oil pool; 701-fixture structure; 702-groove; 703-positioning bolt; 72-vacuum adsorption chuck; 8-positioning platform motion unit. DETAILED DESCRIPTION

[0035] The present application is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and cannot be used to limit the scope of protection of the present application. It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanation of the present application.

[0036] At present, in order to deal with arc discharge and chip burnout in the high-voltage test of high-power power electronic chips, the main approach is to increase the critical breakdown field strength of the contact medium. There are two traditional methods: one is to drip liquid isolation insulating medium (generally electronic fluoride liquid) on the power electronic chip or immerse it in the isolation insulating medium, and the other is to use high-pressure and high-purity inert gas as a protective gas, and perform inert gas high-pressure purge during the test to reduce the risk of discharge and ignition, and improve test efficiency and safety. However, as the voltage level of power electronic chips gradually increases, the effect of inert gas high-pressure purge is difficult to support ultra-high voltage testing, and the method of dripping liquid isolation insulating medium cannot meet the requirements of ultra-high voltage testing. In addition, the oil pool containing liquid isolation insulating medium in the existing test device lacks flexibility. Generally, the amount of isolation insulating medium in the oil pool needs to be continuously adjusted according to the voltage level of the chip, and the depth of the corresponding oil pool is largely limited by the design size and specifications of the test probe itself, resulting in the existing device being difficult to flexibly cope with tests of different voltage levels. Therefore, the present application proposes a high-voltage testing device for high-power power electronic chips, which has the characteristics of adjustable distance between the test probe and the oil pool, changeable oil pool height, and replaceable test probe to meet the automation requirements of high-voltage testing of high-power power electronic chips.

[0037] Combination Figure 1 and Figure 2 As shown, an embodiment of the present application discloses a high-voltage testing device for high-power power electronic chips, the device comprising a test host device 2, a high-voltage test source meter device 3, a microscopic imaging device 4, a probe assembly 5, a probe adjustment unit 6, a wafer positioning platform 7, a positioning platform motion unit 8 and a fixed base 1.

[0038] Specifically, the wafer positioning platform 7 is used to fix the power electronic chip during the testing phase. The wafer positioning platform 7 is placed on the positioning platform motion unit 8. The positioning platform motion unit 8 carries the chip in the wafer positioning platform 7 to move within a plane. The positioning platform motion unit 8 is installed at the bottom position of the fixed base 1.

[0039] In more detail, the wafer positioning platform 7 described in the present application includes an oil pool 71 made of a high-conductivity metal material and a vacuum adsorption chuck 72, wherein the oil pool 71 is made of a high-conductivity metal material in order to minimize the contact resistance between the oil pool 71 and the chip; the surface of the vacuum adsorption chuck 72 is also made of a high-conductivity metal material, preferably a high-conductivity material such as gold plating or pure gold, to reduce the contact resistance between the oil pool 71 and the vacuum adsorption chuck 72. A accommodating cavity for placing a power electronic chip is provided in the middle of the oil pool 71, and the accommodating cavity is used to contain the chip and a liquid isolation insulating medium. In addition, at least one clamp structure 701 is provided on the upper edge of the side wall of the accommodating cavity, and the power electronic chip is held close to the bottom of the accommodating cavity through the clamp structure 701, such as Figure 3 As shown, in this embodiment, two clamp structures 701 are provided on the upper edge of the side wall of the accommodating cavity, and the two clamp structures 701 are arranged opposite to each other. It should be noted that the specific structure of the clamp structure 701 is not limited, and it can play the role of applying pressure to the power electronic chip to make the chip close to the bottom of the accommodating cavity, such as a spring pressure piece with a certain elastic force. In addition, the clamp structure 701 is generally made of high insulation materials, including but not limited to polytetrafluoroethylene and other materials.

[0040] The vacuum adsorption chuck 72 is fixedly connected to the positioning platform motion unit 8, and a plurality of through holes are provided on the surface of the vacuum adsorption chuck 72, and a vacuum pipeline connecting the through holes is provided under the vacuum adsorption chuck 72. Negative pressure is provided by the vacuum pipeline to discharge the air between the oil pool 71 and the vacuum adsorption chuck 72, so that the oil pool 71 is stably fixed on the vacuum adsorption chuck 72. Furthermore, in this embodiment, a positioning through hole connected to the oil pool 71 is provided on the side of the vacuum adsorption chuck 72, and a connector matching the vacuum adsorption chuck 72 is provided at the bottom of the oil pool 71. A positioning bolt 703 matching the positioning through hole is provided on the connector, and the oil pool 71 is fixed to the vacuum adsorption chuck 72 by the positioning bolt 703 and the positioning through hole. At the same time, the oil pool 71 and the vacuum adsorption chuck 72 can be connected to the same potential by the positioning bolt 703 to reduce the direct contact resistance between the oil pool 71 and the vacuum adsorption chuck 72.

[0041] It should be noted that, in this embodiment, the positioning platform motion unit 8 mainly carries the chip to move in the X direction, Y direction and θ (rotation) direction, so as to realize the positioning and mobile testing of the chips at different positions. The specific structure of the positioning platform motion unit 8 is not limited in detail, and any structure that can realize translation and rotation within the plane range is possible, such as a slewing bearing and guide rail combination structure. In addition, the bottom of the accommodating cavity of the oil pool 71 in this embodiment needs to be processed very flat to ensure that the chip and the oil pool 71 fit closely and reduce the contact resistance to the greatest extent. And at least one thin strip-shaped groove 702 is provided at the bottom of the oil pool 71, and the groove 702 can assist the power electronic chip to detach from the bottom of the oil pool 71. For example, in this embodiment, one or two thin strip-shaped grooves 702 are designed, and the length of the groove 702 is 20 mm, and the width and depth are 0.5 mm.

[0042] The probe assembly 5 described in the present application is used to perform connection testing on the power electronic chip in the wafer positioning platform 7. The probe assembly 5 is located above the wafer positioning platform 7, and the probe assembly 5 is connected to the fixed base 1 through the probe adjustment unit 6. The relative position of the probe assembly 5 and the wafer positioning platform 7 is controlled by the probe adjustment unit 6.

[0043] Specifically, the probe adjustment unit 6 includes a probe support platform 601 and a height adjustment unit 602, and the probe support platform 601 is adjusted in height in the up and down directions by the height adjustment unit 602; the upper surface of the probe support platform 601 is provided with a magnetic metal layer, and the lower surface of the probe support platform 601 is provided with an insulating layer made of a high dielectric constant insulating medium material. The probe support platform 601 described in the present application is a table for supporting the probe assembly 5 for uniform placement. The probe support platform 601 is not in direct contact with the vacuum adsorption chuck 72, and because the upper surface of the probe support platform 601 is a magnetic metal layer, such as iron material, it is convenient for the probe assembly 5 to be magnetically attached to the probe support platform 601, and the lower surface is attached with a high dielectric constant insulating medium material, with wood, rubber, etc. as conventional materials, and its purpose is to isolate the high voltage from the items on the probe support platform 601 during chip testing to prevent discharge and sparking due to air breakdown under high voltage conditions, causing safety accidents.

[0044] Further, the probe assembly 5 includes a test probe and a needle holder. The needle holder is fixed on the probe support platform 601 by magnetic attraction, and can flexibly adjust the fixed position. The needle holder has the functions of front and back fine adjustment and up and down adjustment, which is convenient for positioning the chip for needle testing. In addition, the needle holder is provided with a cable for transmitting electrical signals; the test probe is fixed on the needle holder, and the test probe is electrically connected to the cable on the needle holder. In this embodiment, the test probe needs to have pressure resistance and current resistance, and can meet the test requirements of other electrical performance parameters such as high voltage and high current of the chip. It should be emphasized that the radius of curvature of the tip of the test probe in this embodiment is smaller than the minimum electrode area of ​​the power electronic chip, so that the test probe can be connected to the electrodes at different positions to ensure stable electrical connection of the chip during the test. In addition, the length of the probe in this embodiment can be adapted according to the height of the side wall of the oil pool 71, and the depth of the accommodating cavity of the oil pool 71 is adapted according to the test voltage level of the power electronic chip, and the higher the test voltage level of the power electronic chip, the deeper the depth of the accommodating cavity. For example, the height of the oil pool 71 described in this embodiment can be designed to be 5mm, 10mm, 20mm, 30mm, 50mm and other heights of the oil pool 71; and the test probe is made of metal such as tungsten, and test probes of different lengths are designed for oil pools 71 of different heights to match the height specifications of the oil pool 71.

[0045] Furthermore, the height adjustment unit 602 in this embodiment may adopt a mechanical positioning slot or an automatic lifting method. Figure 1 As shown, in this embodiment, a plurality of mechanical positioning slots can be vertically arranged in the middle portion of the fixed base 1, and the plurality of mechanical positioning slots can be designed and processed with equal or unequal spacing. Correspondingly, a mechanical connection block adapted to the mechanical positioning slot is provided on one side of the probe support platform 601. When the probe support platform 601 needs to be raised, the probe support platform 601 can be manually separated from the current mechanical positioning slot, and after being moved upward to an appropriate position, the mechanical connection block of the probe support platform 601 can be re-engaged into the mechanical positioning slot at the corresponding position. Alternatively, as Figure 2 As shown, in this embodiment, an electric screw motor drive structure or a motor and conveyor belt combination structure is set in the middle part of the fixed base 1, and the motor speed and angle are controlled by electrical signals to drive the probe support platform 601 to rise or fall.

[0046] The microscopic imaging device 4 and the high-voltage test source meter device 3 are both arranged above the probe assembly 5, and the high-voltage test source meter device 3 is electrically connected to the probe assembly 5, for example, a connecting line is used to transmit the test probe related signal and the signal between the high-voltage test source meter device 3. The microscopic imaging device 4 is used to magnify and observe the power electronic chip, and the high-voltage test source meter device 3 is used to apply an electrical signal to the power electronic chip and detect the electrical characteristics. In detail, the microscopic imaging device 4 in this embodiment can be raised and lowered, which is convenient for switching between the microscopic focusing state and the macroscopic state of the naked eye, wherein the microscopic imaging device 4 is mainly a stereo microscope or a telephoto optical microscope, which is convenient for long-distance focusing of the chip above the oil pool 71 at different depths. The microscopic imaging device 4 presents the image observed in the lens on the computer monitor through a charge coupled device (CCD), which is convenient for observing and adjusting the chip.

[0047] The test host device 2 is located above the probe assembly 5, and the test host device 2 is installed on the top of the fixed base 1. The test host device 2 is electrically connected to the high-voltage test source meter device 3, the probe adjustment unit 6, and the positioning platform motion unit 8, respectively. The test host device 2 is used to control the test process and receive test data. Generally, the test host device 2 includes at least a computer host, a display, a mouse, a keyboard, and a probe station control software, etc., which can control the test probe, including the establishment of a distribution map of the chip, the motion control of the probe station, and chip dotting.

[0048] More specifically, in order to prevent the influence of external vibration on the test results, a honeycomb vibration isolation structure is provided at the bottom of the fixed base 1 in this embodiment, and the influence of external vibration on the test process can be eliminated through the honeycomb vibration isolation structure.

[0049] In addition, based on the above-mentioned high-power electronic chip high-voltage testing device, the present application also discloses a high-voltage testing method for a high-power electronic chip, the method comprising the following steps:

[0050] Before testing, the probe adjustment unit 6 is raised and the wafer positioning platform 7 is fixed on the positioning platform motion unit 8;

[0051] Place the power electronic chip into the oil pool 71 of the wafer positioning platform 7, and lower the probe adjustment unit 6 to a preset height;

[0052] Select a probe assembly 5 that matches the oil pool 71 and install it on the probe adjustment unit 6, and level the wafer positioning platform 7;

[0053] Inject a preset height of an isolation dielectric into the oil pool 71 of the wafer positioning platform 7, connect the probe assembly 5 to the high-voltage test source meter device 3, and set test parameters for the high-voltage test source meter device 3;

[0054] The probe assembly 5 performs connection tests on the power electronic chips in the wafer positioning platform 7 in sequence according to a preset test sequence;

[0055] After each test of an area of ​​the power electronic chip is completed, the probe assembly 5 is raised and the test data is saved; then the next area of ​​the power electronic chip is replaced and the test is continued until all areas of the power electronic chip are tested;

[0056] After all areas of the power electronic chip are tested, the probe adjustment unit 6 is raised, the oil pool 71 is removed, the next power electronic chip is replaced and the test is continued.

[0057] It should be understood that "one embodiment" or "an embodiment" mentioned throughout the specification means that specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application. The above-mentioned sequence numbers of the embodiments of the present application are only for description and do not represent the advantages and disadvantages of the embodiments.

[0058] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0059] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or components can be combined, or can be integrated into another device, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0060] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed on multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0061] In addition, all functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may be a separate unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0062] A person skilled in the art can understand that all or part of the steps of implementing the above method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM), magnetic disks or optical disks, etc., various media that can store program codes.

[0063] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application can essentially or in other words, the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a device (which can be a terminal or a platform, etc.) to execute all or part of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0064] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A high voltage test device for high power electronic chips, characterized in that: The device comprises a test host device, a high voltage test source meter device, a microscopic imaging device, a probe assembly, a probe adjustment unit, a wafer positioning platform, a positioning platform motion unit and a fixed base; The wafer positioning platform is used to fix the power electronic chip during the test phase. The wafer positioning platform is placed on the positioning platform motion unit. The positioning platform motion unit carries the chip in the wafer positioning platform to move within a plane. The positioning platform motion unit is installed at the bottom of the fixed base. The probe assembly is used to perform connection test on the power electronic chip in the wafer positioning platform. The probe assembly is located above the wafer positioning platform, and the probe assembly is connected to the fixed base through a probe adjustment unit. The relative position of the probe assembly and the wafer positioning platform is controlled by the probe adjustment unit. The microscopic imaging device and the high-voltage test source meter device are both arranged above the probe assembly, and the high-voltage test source meter device and the probe assembly are electrically connected, the microscopic imaging device is used to magnify and observe the power electronic chip, and the high-voltage test source meter device is used to apply an electrical signal to the power electronic chip and detect electrical characteristics; The test host device is located above the probe assembly and is installed on the top of the fixed base. The test host device is electrically connected to the high-voltage test source meter device, the probe adjustment unit, and the positioning platform motion unit respectively. The test host device is used to control the test process and receive test data.

2. The high voltage testing device for high power electronic chips according to claim 1 is characterized in that: The wafer positioning platform includes an oil pool made of high-conductivity metal material and a vacuum adsorption chuck. A accommodating cavity for placing a power electronic chip is provided in the middle of the oil pool. At least one clamp structure is provided on the upper edge of the side wall of the accommodating cavity, and the power electronic chip is pressed tightly against the bottom of the accommodating cavity through the clamp structure; the vacuum adsorption chuck is fixedly connected to the positioning platform motion unit, and a plurality of through holes are provided on the surface of the vacuum adsorption chuck, and a vacuum pipeline connecting the through holes is provided under the vacuum adsorption chuck.

3. The high voltage testing device for high power electronic chips according to claim 2 is characterized in that: A positioning through hole is provided on the side of the vacuum adsorption chuck, a connector matching the vacuum adsorption chuck is provided at the bottom of the oil pool, and a positioning bolt matching the positioning through hole is provided on the connector. The oil pool is fixed to the vacuum adsorption chuck through the positioning bolt and the positioning through hole.

4. The high voltage testing device for high power electronic chips according to claim 2 is characterized in that: The bottom of the oil pool is provided with at least one groove in the form of a thin strip, and the groove is used to assist the power electronic chip to separate from the bottom of the oil pool.

5. The high voltage testing device for high power electronic chips according to claim 2 is characterized in that: The depth of the accommodating cavity of the oil pool is adapted according to the test voltage level of the power electronic chip, and the higher the test voltage level of the power electronic chip, the deeper the depth of the accommodating cavity.

6. The high voltage testing device for high power electronic chips according to claim 1, characterized in that: The probe adjustment unit includes a probe support platform and a height adjustment unit, and the probe support platform is adjusted in height in the up and down directions through the height adjustment unit; the upper surface of the probe support platform is provided with a magnetic metal layer, and the lower surface of the probe support platform is provided with an insulating layer using a high dielectric constant insulating medium material; the height adjustment unit adopts a mechanical positioning slot or an automatic lifting method.

7. The high voltage testing device for high power electronic chips according to claim 6 is characterized in that: The probe assembly includes a test probe and a needle holder. The needle holder is fixed to the probe support platform by magnetic attraction. The needle holder is provided with a cable for transmitting electrical signals. The test probe is fixed on the needle holder, and the test probe is electrically connected to the cable on the needle holder.

8. The high voltage testing device for high power electronic chips according to claim 7 is characterized in that: The curvature radius of the tip of the test probe is smaller than the minimum electrode area of ​​the power electronic chip.

9. The high voltage testing device for high power electronic chips according to claim 1, characterized in that: A honeycomb vibration isolation structure is provided at the bottom of the fixed base, and the honeycomb vibration isolation structure is used to eliminate the vibration influence of the outside world on the test process.

10. A high voltage testing method for high power electronic chips, characterized in that: The method is applied to the high-power power electronic chip high-voltage test device according to any one of claims 1 to 9, and the method comprises the following steps: Before testing, the probe adjustment unit is raised and the wafer positioning platform is fixed on the positioning platform motion unit; Place the power electronic chip into the oil pool of the wafer positioning platform and lower the probe adjustment unit to a preset height; Select a probe assembly that matches the oil pool and install it on the probe adjustment unit, and level the wafer positioning platform; Inject a preset height of an isolation dielectric into the oil pool of the wafer positioning platform, connect the probe assembly to the high-voltage test source meter device, and set test parameters for the high-voltage test source meter device; The probe assembly performs connection tests on the power electronic chips in the wafer positioning platform in sequence according to a preset test sequence; After each test is completed on an area of ​​the power electronic chip, the probe assembly is raised and the test data is saved; Then, the next area of ​​the power electronic chip is replaced and the test is continued until all areas of the power electronic chip are tested; After all areas of the power electronic chip are tested, the probe adjustment unit is raised, the oil pool is removed, the next power electronic chip is replaced and the test continues.

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