Automatic reset 3d trimming test hardware and method for to356 test chip

Abstract

This invention discloses an automatic reset three-dimensional fine-tuning test hardware and method adapted to TO356 test chips, belonging to the field of chip testing technology. It includes a universal three-dimensional fine-tuning base and a detachable TO356 test socket mounted on top of it. The universal three-dimensional fine-tuning base is quickly fixed to the test equipment via a basic mounting locking component, and achieves precise alignment along the XYZ axes through the three-dimensional fine-tuning component. The TO356 test socket adopts a dual-test-chip independent conductive structure, combined with an automatic reset chip carrier component to achieve rapid chip loading and unloading and stable electrical contact. An anti-displacement fixing component ensures the reliability of high-current testing. This invention also provides corresponding testing methods, covering all dimensions of testing including electrical parameters, performance, reliability, and fault coverage. This invention solves the industry pain points of low alignment accuracy, slow changeover, insufficient current carrying capacity, and low testing efficiency in existing TO356 chip testing, significantly improving testing accuracy and greatly shortening changeover time. It can be widely applied to batch testing scenarios for power semiconductor chips.

Description

Technical Field

[0001] This invention relates to the field of chip testing technology, and in particular to an automatic reset three-dimensional fine-tuning test hardware and method adapted to TO356 test chips. Background Technology

[0002] The TO356 package, with its excellent heat dissipation and mechanical strength, has become the mainstream packaging form for high-power semiconductor chips such as IGBTs and MOSFETs, and is widely used in high-end equipment fields such as new energy vehicle electronic control, industrial motor drives, and photovoltaic inverters. As downstream industries continue to increase their requirements for the current rating, switching speed, and reliability of power devices, chip factory testing has evolved from sampling inspection of single electrical parameters to batch automated testing covering all operating conditions and the entire life cycle. This has placed unprecedentedly stringent requirements on the alignment accuracy, current carrying capacity, testing efficiency, and versatility of test hardware.

[0003] Existing TO356 chip testing hardware is mostly based on traditional single-test-chip integrated structure design. When facing the testing requirements of next-generation high-power chips, it has gradually exposed multiple technical limitations: First, the position adjustment mechanism mostly adopts coarse adjustment or single-axis adjustment methods, which makes it difficult to balance adjustment efficiency and alignment accuracy. The contact consistency between chip pins and test chip is poor, which easily leads to large dispersion of test data. Second, the current carrying capacity and heat dissipation capacity of a single test chip are mutually restrictive. During high-current testing, the temperature rise of the test chip is significant, which not only affects the accuracy of test results, but also accelerates the oxidation and deformation of the test chip and shortens its service life. Third, the chip support mechanism mostly adopts a fixed or semi-automated design, which cannot adapt to the continuous loading and unloading requirements of high-speed automated production lines, making it difficult to further improve testing efficiency. Fourth, the test socket and mounting base are mostly integrated custom structures. Testing different models of chips requires replacing the entire set of hardware, which has a long changeover and high cost, making it difficult to meet the flexible testing requirements of multiple varieties and small batches.

[0004] The aforementioned technical problems are interconnected and mutually restrictive, and cannot be solved by simple improvements to a single structure. How to simultaneously achieve high-precision three-dimensional alignment, stable high-current bearing capacity, automated rapid loading and unloading, and modular universal replacement while ensuring testing reliability has become a key technical challenge that urgently needs to be overcome in this field. Summary of the Invention

[0005] In view of this, this application provides an automatic reset three-dimensional fine-tuning test hardware and method adapted to TO356 test chip to solve the shortcomings of the prior art.

[0006] The first aspect of this application provides an automatic reset three-dimensional fine-tuning test hardware adapted to TO356 test chips, comprising: Three-dimensional fine-tuning universal base 100 and TO356 test socket 200 detachably connected to the top of the three-dimensional fine-tuning universal base 100; The three-dimensional fine-tuning universal base 100 includes a mounting block 110, a base body 101, a basic mounting locking component, and a three-dimensional fine-tuning component. The mounting block 110 is used to fix the base body 101 on the chip testing machine station. The basic mounting locking component detachably locks the base body 101 onto the mounting block 110. The three-dimensional fine-tuning component is used to drive the base body 101 to achieve X-axis and Y-axis translation, and to drive the TO356 test socket 200 to achieve Z-axis position adjustment, thereby completing the three-axis precise alignment of the chip under test 204 and the TO356 test piece. The TO356 test socket 200 includes a test socket body 201, an automatic reset chip carrier assembly, a dual test piece mounting assembly, and an anti-displacement fixing assembly. The test socket body 201 is in transmission cooperation with the three-dimensional fine-tuning assembly. The dual test piece mounting assembly is configured with two independent TO356 test pieces, each corresponding to a different pin partition of the chip under test 204. The automatic reset chip carrier assembly is used to place the chip under test 204, and slides vertically to a limited position under downward pressure to achieve electrical contact between the pins of the chip under test 204 and the test piece, and automatically springs back to reset after the downward pressure is removed. The anti-displacement fixing assembly is used to limit and clamp the test piece.

[0007] Furthermore, the basic mounting locking assembly includes a mounting groove 108 at the bottom of the base body 101, a fixing rod 107 passing through the side wall of the base body 101, a pin 109 fixed on the fixing rod 107, and a limiting spring 111 sleeved on the end of the fixing rod 107; the mounting groove 108 is slidably adapted to the mounting block 110, and the mounting block 110 is provided with a locking groove adapted to the fixing rod 107; the fixing rod 107 is inserted into the locking groove 116 to achieve initial positioning of the base body 101, the fixing rod 107 is rotated to make the pin 109 press against the side wall of the mounting block 110, and the limiting spring 111 provides axial preload force to lock the base body 101 and the mounting block 110 into one unit.

[0008] Furthermore, the three-dimensional fine-tuning component includes an X-axis adjustment unit, a Y-axis adjustment unit, and a Z-axis adjustment unit; The X-axis adjustment unit is a threaded adjustment rod 102. The threaded adjustment rod 102 presses against the mounting block 110 and the base body 101, and drives the base body 101 to move along the X-axis through threaded transmission and achieves self-locking. The Y-axis adjustment unit includes a Y-axis eccentric wheel component 103 and a Y-axis locking component. The Y-axis eccentric wheel component 103 is rotatably mounted on the base body 101. When rotating, it drives the base body 101 to move as a whole along the Y-axis and is positioned by the Y-axis locking component and the locking hole 106. The Z-axis adjustment unit includes a Z-axis eccentric wheel component 104, a Z-axis locking component, and an elongated mounting hole 105 opened on the top of the base body 101. The elongated mounting hole 105 is arranged along the Z-axis adjustment direction. The test seat body 201 is connected to the base body 101 through the elongated mounting hole 105 by fasteners. The Z-axis eccentric wheel component 104 pushes the test seat body 201 along the elongated mounting hole 105 to achieve Z-axis position sliding adjustment and is positioned by the Z-axis locking component. Both the Y-axis eccentric wheel component 103 and the Z-axis eccentric wheel component 104 are coaxially fixed with a scale for visually indicating the displacement.

[0009] Furthermore, the dual test piece mounting assembly includes a first test piece 209, a second test piece 210, and a circuit board 202; The first test piece 209 and the second test piece 210 are independent conductive test pieces, respectively corresponding to the pin arrangement on both sides of the chip under test 204; The first test piece 209 and the second test piece 210 are respectively fixed on the independent circuit partitions of the split circuit board 202, each forming an independent conductive path.

[0010] Furthermore, the first test piece 209 and the second test piece 210 are made of a high conductivity alloy material. The lower end of the test piece is fixedly connected to the split circuit board 202, and the upper end of the test piece is provided with an arc-shaped contact end for flexible contact with the pins of the chip under test 204. The test seat body 201 and the base body 101 fit together and slide to form a lateral limit, which is adapted to the travel range of the elongated mounting hole 105 and can be smoothly slid and finely adjusted along the Z direction.

[0011] Furthermore, the automatic reset chip carrier assembly includes a chip support plate 211, a slider 205, a reset spring 214, and a fixing bracket 206; The chip support plate 211 forms a vertical sliding pair with the fixed bracket 206 via the slider 205, and the reset spring 214 is assembled between the sliding strokes to provide reset elasticity; The chip support plate 211 is provided with a positioning groove 212 that is adapted to the shape of the chip under test 204; The chip support plate 211 has a limiting structure 213 at its bottom, which limits its downward sliding limit.

[0012] Furthermore, the anti-displacement fixing assembly includes a test plate pressure plate 203 and a locking fastener 207; The lower surface of the test piece pressure plate 203 is provided with a limiting groove 208 that matches the shape of the two test pieces. The test piece pressure plate 203 is pressed and fixed on the test seat body 201 by a locking fastener 207. The limiting groove 208 covers the outer side of the test piece to form a gap limiting fit.

[0013] The second aspect of this application provides an automatic reset three-dimensional fine-tuning test method for adapting to TO356 test chips, implemented using the test hardware described in any of the above claims, including the following steps: S100. Fix the mounting block 110 to the preset station of the chip tester, slide the base body 101 onto the mounting block 110 through the bottom mounting groove 108, and operate the basic mounting locking component to lock and fix the base body 101. S200: Sequentially operate the X-axis, Y-axis and Z-axis adjustment units of the three-dimensional fine-tuning component to adjust the spatial position of the test base body 201 and the test piece, and lock each adjustment unit after the test piece pins are precisely aligned with the pins of the chip under test 204. S300: Perform continuity testing on each test piece of the dual test piece mounting assembly to check for pin open circuits and short circuits. S400: Place the chip under test 204 in the positioning groove 212 of the chip support plate 211, press the chip down with the nozzle of the test machine, and make the chip support plate 211 slide vertically. The chip pins and the test chip pins make reliable contact and conduction, and carry out various tests on the chip. S500 After the test is completed, the pressure is removed, and the reset spring 214 drives the chip support plate 211 to automatically spring back and reset, and the tested chip is taken away to complete the sorting and unloading.

[0014] Furthermore, the X-axis adjustment relies on the self-damping of the thread to achieve position self-locking, while the Y-axis and Z-axis are positioned by stepless fine adjustment through the eccentric wheel component; during continuity testing, the independent paths of the two test pieces are tested separately to check for single-pin open circuits and inter-piece crosstalk short circuits.

[0015] Furthermore, the chip tests performed in step S400 include electrical parameter testing, performance testing, reliability testing, and fault coverage testing; The electrical parameter test utilizes two sets of test chips to apply excitation and acquire signals respectively, and tests the chip's conventional electrical characteristic parameters. The performance test includes conduction loss, switching characteristics and temperature rise monitoring, and the test is automatically paused when the chip temperature rise reaches a certain limit. The reliability test includes a power cycle endurance test, and after the cycle, the contact continuity status of the test chip and the stability of the chip's electrical parameters are verified. The fault coverage test includes overcurrent, overvoltage, and overheat protection function tests, as well as simulated detection of poor internal wiring contact. A complete test data report is automatically generated upon completion of the test.

[0016] Its beneficial effects are as follows: Three-dimensional precise alignment significantly improves testing accuracy: The differentiated transmission design of X-axis thread self-locking + Y / Z-axis eccentric wheel stepless fine adjustment achieves high-precision position adjustment of the three axes, solving the problems of large alignment error and poor contact in existing test seats, and significantly improving the accuracy of test results.

[0017] Dual test pieces with independent current carrying capacity: Two independent test pieces are used to correspond to the collector and emitter pins of the chip respectively, forming an independent conductive path, which greatly improves the current carrying capacity and heat dissipation performance, meets the testing requirements of high-power TO356 chips, and extends the service life of the test pieces.

[0018] Automatic reset structure significantly improves testing efficiency: The chip carrier component with spring reset enables the chip to automatically spring back and reset after the test, eliminating the need for manual material handling. This adapts to the high-speed testing requirements of automated production lines and greatly improves testing efficiency.

[0019] Modular design enables rapid changeover and reduces costs: The three-dimensional fine-tuning universal base and the TO356 test socket adopt a detachable connection design. The universal base can be adapted to various test socket models. When changing models, only the test socket body needs to be replaced, without the need to readjust the base. The changeover time is reduced from several hours to several minutes, which significantly reduces testing costs and production line downtime.

[0020] Anti-displacement fixing structure for high test reliability: The test piece is pressed and fixed by a test piece pressure plate with limiting grooves, which effectively prevents the test piece from shifting during high current testing, ensuring the stability of contact resistance and avoiding the risk of test piece burnout and chip damage. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of an automatic reset three-dimensional fine-tuning test hardware adapted to a TO356 test chip, provided in an embodiment of this application. Figure 2 This is a schematic diagram of the overall three-dimensional fine-tuning universal base provided in the embodiments of this application; Figure 3 This is a schematic diagram of the basic installation locking component provided in an embodiment of this application; Figure 4 This is a schematic diagram of the mounting block structure provided in an embodiment of this application; Figure 5 This is a schematic diagram of the Y-axis eccentric wheel component provided in the embodiments of this application (including the Y-axis dial and the Y-axis knob). Figure 6 This is a schematic diagram of the Z-axis eccentric wheel component provided in the embodiments of this application (including the Z-axis dial and the Z-axis knob). Figure 7 This is a schematic diagram of the TO356 test socket provided in the embodiments of this application; Figure 8 This is a partial schematic diagram of the TO356 test socket provided in an embodiment of this application; Figure 9 This is a schematic diagram of the internal structure of the anti-displacement fixing component provided in the embodiments of this application; Figure 10 This is a partial perspective view of the TO356 test socket provided in an embodiment of this application; Figure 11 This is a side view of the three-dimensional fine-tuning universal base provided in the embodiments of this application; Figure 12 This is a flowchart of an automatic reset three-dimensional fine-tuning test method for adapting to TO356 test pieces, provided in an embodiment of this application.

[0023] Among them, 100-3D fine-tuning universal base, 200-TO356 test seat, 101-base body, 102-threaded adjustment rod, 103-Y-direction eccentric wheel component, 104-Z-direction eccentric wheel component, 105-long strip mounting hole, 106-locking hole, 107-fixing rod, 108-mounting slot, 109-pin, 110-mounting block, 111-limiting spring, 112-Y-direction dial, 113-Y-direction knob, 114-... - Z-axis dial, 115- Z-axis knob, 116- Locking groove, 201- Test base body, 202- Circuit board, 203- Test piece pressure plate, 204- Chip under test, 205- Slider, 206- Fixing bracket, 207- Locking fastener, 208- Limiting groove, 209- First test piece, 210- Second test piece, 211- Chip support plate, 212- Positioning groove, 213- Limiting structure, 214- Reset spring. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] In this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0026] Example The existing TO356 chip testing hardware has the following core defects: Low alignment accuracy and difficult adjustment: Most test sockets adopt a fixed installation method, which cannot achieve three-dimensional fine adjustment, or can only achieve single-axis / dual-axis coarse adjustment. The alignment error between chip pins and test pieces is large, which can easily lead to problems such as poor contact and pin deformation, resulting in distorted test results. Insufficient current carrying capacity: The test chip is generally integrated into a single test chip structure. During high current testing, the test chip heats up severely, is prone to oxidation and deformation, has a short service life, and cannot meet the testing requirements of high-power TO356 chips. No automatic reset function: After the test is completed, the chip needs to be removed manually, which results in low testing efficiency, cannot meet the high-speed testing requirements of automated production lines, and manual operation is prone to chip damage. High cost and long cycle for switching: Testing different chip models requires replacing the entire test socket, resulting in low standardization and long debugging time for switching, which increases testing costs and production line downtime. Test piece is prone to displacement: During high current testing, the test piece is prone to displacement due to electromagnetic force and thermal stress, which leads to increased contact resistance, affects test accuracy, and in severe cases, can cause the test piece to burn out. Therefore, this application provides an automatic reset three-dimensional fine-tuning test hardware adapted to the TO356 test chip, the overall structure of which is as follows: Figure 1As shown, it mainly consists of two parts: a 3D fine-tuning universal base 100 and a TO356 test socket 200. The TO356 test socket 200 is detachably mounted on top of the 3D fine-tuning universal base 100. The 3D fine-tuning universal base 100 is responsible for enabling quick installation and 3D position fine-tuning, while the TO356 test socket 200 is responsible for chip support, electrical contact, and automatic reset. Together, they complete the entire testing process for the TO356 chip.

[0027] The specific structure of the 3D fine-tuning universal base 100 is as follows: like Figure 2 As shown, the three-dimensional fine-tuning universal base 100 includes a mounting block 110, a base body 101, a basic mounting locking component, and a three-dimensional fine-tuning component.

[0028] 1. Basic installation locking components like Figure 3 and Figure 4 As shown, the basic mounting locking assembly includes a mounting groove 108, a fixing rod 107, a pin 109, and a limiting spring 111. The mounting groove 108 is formed at the bottom of the base body 101 and slides to fit the upper part of the mounting block 110. The side of the mounting block 110 has a locking groove 116 that matches the diameter of the fixing rod 107. The fixing rod 107 is horizontally inserted through the side wall of the base body 101, the pin 109 is vertically fixed to the middle of the fixing rod 107, and the limiting spring 111 is sleeved on the front end of the fixing rod 107, located between the end of the fixing rod 107 and the inner wall of the base body 101.

[0029] During installation, the base body 101 is pushed horizontally into the mounting block 110 through the bottom mounting groove 108. When the fixing rod 107 is engaged in the locking groove of the mounting block 110, the base body 101 is initially limited in the Y-axis and Z-axis directions. At this time, the fixing rod 107 is rotated so that the end of the pin 109 abuts against the side wall of the mounting block 110. The limiting spring 111 is compressed and provides axial preload, which firmly locks the base body 101 and the mounting block 110 together to prevent shaking during the test.

[0030] 2. Three-dimensional fine-tuning component The three-dimensional fine-tuning component includes an X-axis adjustment unit, a Y-axis adjustment unit, and a Z-axis adjustment unit, which respectively realize position adjustment along the three axes.

[0031] X-axis adjustment unit: A threaded adjustment rod 102 is horizontally mounted on the side wall of the base body 101, with its end pressing against the side of the mounting block 110. When the threaded adjustment rod 102 is rotated, the base body 101 is moved along the X-axis direction through threaded transmission. After adjustment, the position is self-locked by the damping of the thread itself, without the need for additional locking components.

[0032] Y-axis adjustment unit: such as Figure 5 As shown, the system includes a Y-axis eccentric wheel component 103 and a Y-axis locking component. The Y-axis eccentric wheel component 103 is coaxially fixed by a Y-axis dial 112 and a Y-axis knob 113, and is rotatably mounted on the upper part of the base body 101. When the Y-axis knob 113 is rotated, the eccentric wheel portion of the Y-axis eccentric wheel component 103 pushes the base body 101 to move as a whole along the Y-axis direction. The Y-axis dial 112 is evenly marked with graduations, which can intuitively indicate the displacement. After adjustment, the Y-axis locking component is tightened so that it is inserted into the locking hole 106 on the base body 101 to lock the Y-axis position.

[0033] Z-axis adjustment unit: such as Figure 6 and Figure 11 As shown, the device includes a Z-axis eccentric wheel component 104, a Z-axis locking component, and a long mounting hole 105. The long mounting hole 105 is located on the top of the base body 101 and extends along the Z-axis adjustment direction. The test seat body 201 is connected to the base body 101 via bolts or other fasteners passing through the long mounting hole 105. The Z-axis eccentric wheel component 104 is coaxially fixed by a Z-axis dial 114 and a Z-axis knob 115, and is rotatably mounted at the end of the base body 101, with its eccentric wheel portion pressing against the side of the test seat body 201. When the Z-axis knob 115 is rotated, the Z-axis eccentric wheel component 104 pushes the test seat body 201 to translate along the length direction of the long mounting hole 105, and the Z-axis dial 114 is used to indicate the displacement. After adjustment, the fasteners in the Z-axis locking component and the long mounting hole 105 are tightened to lock the Z-axis position.

[0034] The bottom surface of the test base body 201 is closely fitted and slidably engaged with the top surface of the base body 101. The top surface of the base body 101 has raised lateral limiting edges on both sides to limit the offset of the test base body 201 in the Y-axis direction, ensuring that it can only slide smoothly and make minor adjustments in the Z-axis direction, which is fully compatible with the travel range of the elongated mounting hole 105.

[0035] The specific structure of the TO356 test socket 200 is as follows: like Figure 7 and Figure 8 As shown, the TO356 test socket 200 includes a test socket body 201, an automatic reset chip carrier assembly, a dual test piece mounting assembly, and an anti-displacement fixing assembly.

[0036] 1. Dual test piece mounting assembly like Figure 9 and Figure 10As shown, the dual test strip mounting assembly includes a first test strip 209, a second test strip 210, and a separate circuit board 202. Both the first test strip 209 and the second test strip 210 are made of highly conductive copper alloy, possessing good conductivity and wear resistance. The two test strips are symmetrically arranged on both sides of the chip support plate 211. The first test strip 209 corresponds to the collector-side pin of the chip under test 204, and the second test strip 210 corresponds to the emitter-side pin of the chip under test 204.

[0037] The lower end of the test piece is soldered to a split circuit board 202, which is divided into two independent circuit partitions, left and right. The first test piece 209 and the second test piece 210 are soldered to their respective partitions, forming independent conductive paths to avoid mutual interference during high-current testing. The upper end of the test piece is designed with an arc-shaped contact tip, which can flexibly fit and conduct with the pins of the chip under test 204, reducing pin damage.

[0038] 2. Automatic reset chip carrier assembly like Figure 10 As shown, the automatic reset chip carrier assembly includes a chip support plate 211, sliders 205, a reset spring 214, and a fixing bracket 206. The fixing bracket 206 is vertically fixed on the test base body 201. Two sliders 205 are symmetrically installed on both sides of the fixing bracket 206. The two sides of the chip support plate 211 are fixedly connected to the sliders 205, and the sliders 205 and the fixing bracket 206 form a vertical sliding pair.

[0039] A reset spring 214 is sleeved on the guide post of the slider 205, with its upper end abutting the bottom of the chip support plate 211 and its lower end abutting the bottom of the fixing bracket 206, providing an upward reset force for the chip support plate 211. The chip support plate 211 has a positioning groove 212 at its center that perfectly matches the shape of the chip under test 204, for precise placement of the chip under test 204. The bottom of the chip support plate 211 has a limiting structure 213. When the chip support plate 211 slides downward to its limit position, the limiting structure 213 abuts against the bottom of the fixing bracket 206, limiting its further downward movement and preventing excessive pressure that could damage the test chip and chip pins.

[0040] 3. Anti-displacement fixing components like Figure 9 As shown, the anti-displacement fixing assembly includes a test piece pressure plate 203 and multiple locking fasteners 207. The test piece pressure plate 203 is a rectangular plate structure, and its lower surface has a limiting groove 208 that perfectly matches the shape of the first test piece 209 and the second test piece 210. During installation, the test piece pressure plate 203 is placed over the two test pieces, so that the upper part of the test piece is embedded in the limiting groove 208, and then the test piece pressure plate 203 is pressed and fixed onto the test base body 201 by the locking fasteners 207.

[0041] The inner wall of the limiting groove 208 forms a small gap limiting fit with the side wall of the test piece, which not only does not affect the installation of the test piece, but also effectively prevents the test piece from being laterally displaced by electromagnetic force and thermal stress during high current testing, thus ensuring the stability of the contact resistance.

[0042] Overall working principle and workflow The testing hardware of this invention is used in conjunction with an automated chip testing machine. The complete workflow is as follows: Figure 12 As shown: 1. Hardware installation: Fix the mounting block 110 to the preset position of the chip testing machine with bolts, slide the base body 101 onto the mounting block 110 through the bottom mounting groove 108, push the fixing rod 107 to make it snap into the locking groove of the mounting block 110, and then rotate the fixing rod 107 to make the pin 109 press against the side wall of the mounting block 110 to complete the locking and fixing of the base body 101.

[0043] 2. Three-dimensional alignment adjustment: Activate the vision positioning system of the test machine to identify the positional deviation between the pins of the chip under test 204 and the contact end of the test piece. Rotate the threaded adjustment rod 102, the Y-axis knob 113, and the Z-axis knob 115 sequentially to adjust the positions of the X, Y, and Z axes respectively, reading the displacement through the dial until the pins of the test piece are precisely aligned with the pins of the chip under test 204. After adjustment, tighten the fasteners in the Y-axis locking piece, the Z-axis locking piece, and the elongated mounting hole 105 to lock all adjustment units.

[0044] 3. Pre-test continuity test: The tester applies low-voltage test signals to the first test chip 209 and the second test chip 210 through the split circuit board 202 to check whether all pins of the two test chips are conducting normally, and to check for faults such as single-pin open circuit and inter-chip crosstalk short circuit, to ensure that the test hardware is in good condition.

[0045] 4. Chip Testing: The testing machine's nozzle picks up the chip under test 204 and precisely places it into the positioning groove 212 of the chip support plate 211. The nozzle applies downward pressure, causing the chip support plate 211 to slide downwards along the slider 205 against the force of the return spring 214 until the limiting structure 213 abuts against the fixing bracket 206. At this point, the pins of the chip under test 204 are tightly fitted with the arc-shaped contact end of the test chip, achieving reliable electrical contact. The testing machine automatically starts the testing program and performs various chip tests sequentially.

[0046] 5. Automatic Reset and Unloading: After all tests are completed, the nozzle lifts upwards and the downward pressure is released. The reset spring 214 releases its elasticity, causing the chip support plate 211 and the tested chips to automatically spring back to their initial positions. The nozzle then picks up the chips again and, based on the test results, classifies them into qualified or unqualified trays, completing one test cycle.

[0047] Specific test items and procedures The chip testing performed in step S400 covers four main categories: electrical parameter testing, performance testing, reliability testing, and fault coverage testing. The specific process is as follows: 1. Electrical parameter testing The first test chip 209 applies a test stimulus to the chip, and the second test chip 210 collects the response signal to test the following core electrical parameters in sequence: Saturation voltage drop test: A DC current is applied to the collector of the chip through the first test chip 209, and the voltage between the collector and the emitter is collected through the second test chip 210 to calculate the saturation voltage drop; Reverse breakdown voltage test: With the gate floating, the collector voltage is slowly increased through the first test chip 209. When the collector current reaches the preset value, the reverse breakdown voltage is recorded. Gate threshold voltage test: Apply a gradually increasing voltage through the gate test pin, and record the gate threshold voltage when the collector current reaches a preset value; Leakage current test: With the gate floating and the rated reverse voltage applied, the collector leakage current is measured through the second test chip 210.

[0048] 2. Performance Testing Conduction loss test: The chip is operated in the rated conduction state, and the collector current and collector-emitter voltage are measured at the same time to calculate the conduction loss; Switching characteristic test: Apply a square wave drive signal through the gate test pin, measure the turn-on time and turn-off time of the chip, and calculate the turn-on loss and turn-off loss; Temperature rise monitoring: The chip operates at its rated power, and the surface temperature of the chip is monitored in real time by an infrared thermometer. When the chip temperature rise reaches the preset limit, the test is automatically paused and the test continues after the temperature drops to a safe range to prevent the chip from overheating and being damaged.

[0049] 3. Reliability Testing Perform power cycle endurance testing: The chip is periodically powered on and off at its rated power, with each cycle including a power-on phase and a power-off phase. After completing a preset number of cycles, the contact resistance of the first test chip 209 and the second test chip 210, as well as various electrical parameters of the chip, are measured again to evaluate the durability of the test chips and the stability of the chip parameters.

[0050] 4. Fault coverage test Overcurrent protection test: Apply a current exceeding the rated value through the first test chip 209 to verify whether the chip's overcurrent protection function is triggered normally; Overvoltage protection test: Apply a voltage exceeding the rated value through the first test piece 209 to test whether the chip can withstand it normally or trigger the protection. Overheat protection test: The chip is heated to a preset temperature using a heating device to verify whether the chip's overheat protection function is triggered normally; Internal wiring poor contact test: A pulsed high current is applied through the first test piece 209 to simulate wire detachment or poor contact faults, and to test whether the test system can accurately identify them.

[0051] After all tests are completed, the testing machine automatically generates a complete test report containing all test data, test results, and fault information, which is then stored and uploaded to the production management system.

[0052] Compared with the closest prior art, the distinguishing features of this invention are: the use of a three-dimensional adjustment mechanism with X-axis threaded self-locking and Y / Z-axis eccentric wheel stepless fine adjustment; the use of a dual-test-piece independent current-carrying structure; the use of a spring-driven automatic reset chip-supporting assembly; and the use of a modular and detachable design. These distinguishing features work together to solve several technical problems existing in the prior art.

[0053] This invention addresses the core pain points of existing TO356 chip testing hardware through a systematic and innovative design, achieving significant technological breakthroughs: 1. Breakthrough in alignment accuracy bottleneck: The pioneering three-dimensional adjustment mechanism with X-axis thread self-locking and Y / Z-axis eccentric wheel stepless fine adjustment achieves sub-millimeter level precise alignment, solving the long-standing problems of poor contact and distorted test results that have plagued the industry, and significantly improving test yield.

[0054] 2. Overcame the challenge of high-current testing: Adopting a dual-test-chip independent current-carrying structure, the current-carrying capacity is greatly improved, while the heat dissipation performance is significantly enhanced, meeting the testing requirements of the new generation of high-power TO356 chips and filling a market gap.

[0055] 3. Achieved automated and efficient testing: The design of automatically resetting the chip carrier component completely eliminates the reliance on manual assistance for material handling, significantly shortens the single-chip testing cycle, adapts to the high-speed production rhythm of automated production lines, and greatly increases production capacity.

[0056] 4. A modular and universal testing mode is adopted: The detachable modular design of the universal base and the dedicated test socket realizes a universal testing solution that "one base can be adapted to multiple test sockets", which greatly reduces the procurement cost and replacement cost of test hardware.

[0057] This invention has been practically applied and verified on multiple power semiconductor chip testing production lines. All performance indicators have reached or exceeded the advanced level in the industry, demonstrating extremely high promotional value and economic benefits.

[0058] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0059] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An automatic reset three-dimensional fine-tuning test hardware adapted to TO356 test pieces, characterized in that, Includes a three-dimensional fine-tuning universal base and a TO356 test socket detachably connected to the top of the three-dimensional fine-tuning universal base; The three-dimensional fine-tuning universal base includes a mounting block, a base body, a basic mounting locking component, and a three-dimensional fine-tuning component; the mounting block is used to fix it on the chip testing machine station, and the basic mounting locking component detachably locks the base body onto the mounting block; the three-dimensional fine-tuning component is used to drive the base body to achieve X-axis and Y-axis position translation, and to drive the TO356 test socket to achieve Z-axis position adjustment. The TO356 test socket includes a test socket body, an automatic reset chip carrier assembly, a dual test piece mounting assembly, and an anti-displacement fixing assembly. The test socket body is driven by the three-dimensional fine-tuning assembly. The dual test piece mounting assembly is configured with two independent TO356 test pieces, each corresponding to a different pin partition of the chip under test. The automatic reset chip carrier assembly is used to place the chip under test, and slides vertically to a predetermined position under downward pressure to achieve electrical contact between the pins of the chip under test and the test piece. It automatically springs back to its original position after the downward pressure is removed. The anti-displacement fixing assembly is used to limit and clamp the test piece.

2. The automatic reset three-dimensional fine-tuning test hardware for adapting to TO356 test pieces according to claim 1, characterized in that, The basic mounting locking assembly includes a mounting groove at the bottom of the base body, a fixing rod passing through the side wall of the base body, a pin fixed on the fixing rod, and a limiting spring sleeved on the end of the fixing rod. The mounting groove is slidably adapted to the mounting block, and the mounting block is provided with a locking groove adapted to the fixing rod. The fixing rod is inserted into the locking groove to achieve initial positioning of the base body. Rotating the fixing rod causes the pin to press against the side wall of the mounting block, and the limiting spring provides axial preload force to lock and fix the base body and the mounting block into one piece.

3. The automatic reset three-dimensional fine-tuning test hardware for adapting to TO356 test pieces according to claim 1, characterized in that, The three-dimensional fine-tuning component includes an X-axis adjustment unit, a Y-axis adjustment unit, and a Z-axis adjustment unit; The X-axis adjustment unit is a threaded adjustment rod. The threaded adjustment rod is press-fitted between the mounting block and the base body. The base body is driven to move along the X-axis through threaded transmission and achieves self-locking. The Y-axis adjustment unit includes a Y-axis eccentric wheel component and a Y-axis locking component. The Y-axis eccentric wheel component is rotatably mounted on the base body. When it rotates, it drives the base body to translate along the Y-axis as a whole and is positioned by inserting the Y-axis locking component into the locking hole on the base body. The Z-axis adjustment unit includes a Z-axis eccentric wheel component, a Z-axis locking component, and an elongated mounting hole on the top of the base body. The elongated mounting hole is arranged along the Z-axis adjustment direction. The test seat body is connected to the base body through the elongated mounting hole by fasteners. The Z-axis eccentric wheel component pushes the test seat body along the elongated mounting hole to achieve Z-axis position sliding adjustment and is positioned by the Z-axis locking component. Both the Y-axis eccentric wheel component and the Z-axis eccentric wheel component are coaxially fixed with a scale for visually indicating the displacement.

4. The automatic reset three-dimensional fine-tuning test hardware for adapting to TO356 test pieces according to claim 1, characterized in that, The dual test piece mounting assembly includes a first test piece, a second test piece, and a circuit board; The first test piece and the second test piece are independent conductive test pieces, respectively corresponding to the pin arrangement on both sides of the chip under test; The first test piece and the second test piece are respectively fixed on independent circuit partitions of the split circuit board, each forming an independent conductive path.

5. The automatic reset three-dimensional fine-tuning test hardware for adapting to TO356 test pieces according to claim 4, characterized in that, The first and second test pieces are made of a high-conductivity alloy material. The lower end of the test piece is fixedly connected to the split circuit board, and the upper end of the test piece is provided with an arc-shaped contact end for flexible contact with the pin of the chip under test. The test seat body and the base body fit together and slide to form a lateral limit, which is adapted to the stroke range of the long strip assembly hole and can be smoothly slid and finely adjusted along the Z direction.

6. The automatic reset three-dimensional fine-tuning test hardware for adapting to TO356 test pieces according to claim 1, characterized in that, The automatic reset chip carrier assembly includes a chip support plate, a slider, a reset spring, and a fixing bracket. The chip support plate forms a vertical sliding pair with the slider and the fixed bracket, and the reset spring is assembled between the sliding strokes to provide reset elastic force; The chip support plate is provided with a positioning groove that matches the shape of the chip under test; The bottom of the chip support plate is provided with a limiting structure to limit its downward sliding stroke.

7. The automatic reset three-dimensional fine-tuning test hardware for adapting to TO356 test pieces according to claim 1, characterized in that, The anti-displacement fixing assembly includes a test piece pressure plate and a locking fastener; The lower surface of the test piece pressure plate is provided with a limiting groove that matches the shape of the two test pieces. The test piece pressure plate is pressed and fixed on the test base body by locking fasteners. The limiting groove covers the outer side of the test piece to form a gap limiting fit.

8. An automatic reset three-dimensional fine-tuning test method for adapting to TO356 test pieces, characterized in that, The test is implemented using the test hardware as described in any one of claims 1 to 7, and includes the following steps: S100. Fix the mounting block to the preset station of the chip tester, slide the base body onto the mounting block through the bottom mounting slot, and operate the basic mounting locking component to lock and fix the base body. S200. Sequentially operate the X-axis, Y-axis, and Z-axis adjustment units of the three-dimensional fine-tuning component to adjust the spatial position of the test base body and the test piece, so that the test piece pins are precisely aligned with the pins of the chip under test, and then lock each adjustment unit. S300: Perform continuity testing on each test piece of the dual test piece mounting assembly to check for pin open circuits and short circuits. S400: Place the chip under test in the positioning slot of the chip support board, press down the chip with the nozzle of the tester to make the chip support board slide vertically, and make reliable contact and conduction between the chip pins and the test chip pins to carry out various chip tests. After the S500 test is completed, the pressure is removed, and the reset spring causes the chip support plate to automatically spring back and reset, allowing the tested chips to be removed and sorted.

9. The automatic reset three-dimensional fine-tuning test method for adapting to TO356 test pieces according to claim 8, characterized in that, The X-axis adjustment relies on the self-damping of the thread to achieve position self-locking, while the Y-axis and Z-axis are positioned by stepless fine adjustment through the eccentric wheel component; during continuity testing, the independent paths of the two test pieces are tested separately to check for single-pin open circuits and inter-piece crosstalk short circuits.

10. The automatic reset three-dimensional fine-tuning test method for adapting to TO356 test pieces according to claim 8, characterized in that, The chip tests performed in step S4 include electrical parameter testing, performance testing, reliability testing, and fault coverage testing. The electrical parameter test utilizes two sets of test chips to apply excitation and acquire signals respectively, and tests the chip's conventional electrical characteristic parameters. The performance test includes conduction loss, switching characteristics and temperature rise monitoring, and the test is automatically paused when the chip temperature rise reaches a certain limit. The reliability test includes a power cycle endurance test, and after the cycle, the contact continuity status of the test chip and the stability of the chip's electrical parameters are verified. The fault coverage test includes overcurrent, overvoltage, and overheat protection function tests, as well as simulated detection of poor internal wiring contact. A complete test data report is automatically generated upon completion of the test.

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