A semiconductor laser chip test fixture and method of using the same

Abstract

This invention provides a semiconductor laser chip test fixture and its usage method, which can solve the technical problems of poor chip-to-base contact consistency, high maintenance costs, and weak adaptability to chips of different sizes in existing herringbone-type fixtures. The test fixture includes at least one replaceable conductive compensation layer, which is laid on the base plate and located between the base plate and the chip under test. The conductive compensation layer is made of a ductile conductive and thermally conductive material. The conductive compensation layer is configured to undergo plastic deformation when the cover plate presses the chip under test to compensate for the microscopic gap between the base plate and the chip under test, so that the chip under test forms an electrical connection and thermal conductive contact with the base plate through the conductive compensation layer.

Description

Technical Field

[0001] This invention relates to the field of semiconductor laser chip testing technology, and more specifically to a semiconductor laser chip testing fixture and its usage method. Background Technology

[0002] Optical modules are the core components of optical communication systems, enabling the conversion between photoelectric and electrical signals. Semiconductor laser chips, packaged in COC (Chip On Carrier) form, are the key light-emitting devices in optical modules. Performance testing of semiconductor laser chips, especially high-temperature power aging testing, is a critical quality control step in the optical module manufacturing process. Its purpose is to expose potential internal defects by simulating the actual operating conditions of the device under a set high-temperature environment, thus screening out defective chips. Testing of semiconductor laser chips typically employs specialized fixtures to achieve rapid positioning, clamping, and electrical connection of chips in batches. Among these, the herringbone fixture is widely used due to its compact structure, high chip density, and ease of operation.

[0003] Existing herringbone clamps generally include a base plate, a cover plate, and several elastic pressure claws. In use, the semiconductor laser chip is placed in the positioning groove machined on the base plate. The cover plate presses down to drive the elastic pressure claws to press against the semiconductor laser chip from above, so that the electrodes on the bottom surface of the semiconductor laser chip contact the corresponding test lines on the top surface of the base plate, thus completing the electrical connection and positioning.

[0004] However, during actual use, the applicant discovered the following defects in the existing herringbone clamps: First, it is difficult to guarantee the consistency of contact between the chip and the base plate. As the bearing surface and the basic plane for electrical contact, the surface flatness of the base plate is limited by the processing accuracy and deteriorates with wear over long-term use, making it difficult to maintain absolute consistency. When multiple semiconductor laser chips are placed on the base plate at the same time, there are micron-level differences in the contact state between the bottom surface of each semiconductor laser chip and the base plate, resulting in inconsistent contact impedance of the grounding circuit, introducing test noise, affecting the accuracy of photoelectric parameter testing, and during high-temperature aging, poor contact will cause poor local heat dissipation, further aggravating the dispersion of test results between chips.

[0005] Second, the maintenance cost is high. The base plate is a high-cost precision machined part. Once local wear or indentation occurs on its surface, resulting in poor contact, the existing solution requires the entire base plate to be replaced. After replacement, the positional relationship between the base plate and the elastic clamping component must be recalibrated. The cost of spare parts and downtime are both high, which seriously affects the production cycle.

[0006] Third, the existing rigid base plate has poor adaptability to the size differences of different semiconductor laser chips. It cannot adaptively compensate for the slight thickness differences between different batches of COC chips. It only relies on the upper elastic pressure claw to press the COC chip tightly against the base plate, which can easily cause stress concentration inside the chip or unstable contact state, affecting the chip reliability. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a semiconductor laser chip testing fixture and its usage method, which can solve the technical problems of poor chip-to-base contact consistency, high maintenance costs, and weak adaptability to chips of different sizes in existing herringbone fixtures.

[0008] The technical solution is as follows: A test fixture for semiconductor laser chips includes a base plate and a cover plate. The upper surface of the base plate has multiple chip-carrying areas for carrying the chip to be tested. The cover plate is disposed above the base plate and detachably connected to the base plate. An elastic clamping assembly for pressing and positioning the chip to be tested is disposed between the cover plate and the base plate. The feature is that: The test fixture includes at least one replaceable conductive compensation layer, which is laid on the base plate and located between the base plate and the chip under test. The conductive compensation layer is made of a ductile, conductive, and thermally conductive material. The conductive compensation layer is configured to undergo plastic deformation when the cover plate is pressed against the chip under test by an elastic clamping assembly to compensate for the microscopic gap between the base plate and the chip under test, so that the chip under test forms an electrical connection and thermal conductive contact with the base plate through the conductive compensation layer.

[0009] Furthermore, the conductive compensation layer is a metal sheet, and the material of the metal sheet is any one of pure tin, tin alloy, indium, indium alloy, silver, or silver alloy.

[0010] Furthermore, the thickness of the conductive compensation layer is 0.03 mm to 0.5 mm.

[0011] Furthermore, the conductive compensation layer is a non-adhesive metal sheet, and the conductive compensation layer is fixed to the base plate by the clamping force between the cover plate and the base plate.

[0012] Furthermore, the base plate is provided with positioning marks for indicating the placement range of the conductive compensation layer. The conductive compensation layer covers the base plate according to the positioning marks, and the outer contour of the conductive compensation layer matches the range defined by the positioning marks, so that multiple chips under test can contact the same conductive compensation layer at the same time.

[0013] Furthermore, the conductive compensation layer is configured as a replaceable component; after one or a batch of tests are completed, the conductive compensation layer that has undergone permanent plastic deformation is removed and replaced with a new conductive compensation layer.

[0014] Furthermore, the elastic clamping assembly includes, from bottom to top, a scratch-resistant steel sheet layer, a positioning steel sheet layer, a spring sheet layer, and a feather pressure sheet layer stacked on top of the conductive compensation layer; the spring sheet layer includes multiple elastic pressure claws corresponding one-to-one with each chip to be tested on the chip carrier area, and the ends of the elastic pressure claws abut against the chip to be tested; chip placement grooves are provided on both sides of the scratch-resistant steel sheet layer, and the chip placement grooves cooperate with the base plate to form the chip carrier area; the positioning steel sheet layer has positioning grooves corresponding to the elastic pressure claws; the feather pressure sheet layer includes multiple comb-shaped pressure plates, and the comb-shaped pressure plates are used to apply uniform downward pressure to the elastic pressure claws; the cover plate is detachably connected to the base plate by fasteners, and the fasteners are distributed at both ends of the cover plate.

[0015] A method for using a semiconductor laser chip test fixture, the method being implemented based on the aforementioned semiconductor laser chip test fixture, characterized by comprising the following steps: Step S1: Lay the conductive compensation layer on the upper surface of the base plate; Step S2: Install each layer of the elastic clamping assembly sequentially; Step S3: Place multiple chips to be tested in the chip carrier area and on the upper surface of the conductive compensation layer; Step S4: Cover the cover plate on top of the base plate and connect the cover plate to the base plate with fasteners; apply a pre-compression force in the vertical direction to the conductive compensation layer to initially stabilize the conductive compensation layer, and then apply a working compression force in the vertical direction to cause the conductive compensation layer to undergo plastic deformation under the compression force.

[0016] Furthermore, the magnitude of the working clamping force is configured such that the maximum static friction between the conductive compensation layer and the base plate and the chip under test is greater than 1.5 times the maximum horizontal disturbance force that the test fixture experiences during operation.

[0017] Furthermore, the method also includes a step of replacing the conductive compensation layer: Use a torque tool to loosen the fasteners one by one in a diagonal sequence to detach the cover plate from the base plate; Remove each layer of the elastic clamping assembly in sequence to separate the elastic clamping assembly from the base plate; Remove the old conductive compensation layer that has undergone plastic deformation; Lay the new conductive compensation layer within the area defined by the positioning marks on the base plate; Reassemble the elastic clamping assembly and cover plate.

[0018] Compared with the prior art, the present invention has the following advantages: This invention adds a conductive compensation layer made of a plastically deformable thermally and electrically conductive material between the base plate and the semiconductor laser chip. Under the action of clamping force, the conductive compensation layer undergoes plastic deformation, which can adaptively fill the microscopic gaps formed by the flatness deviation of the base plate surface and the thickness differences between different chips at the microscale, so that all chips can form a uniform and tight surface contact with the base plate. This can reduce the dispersion of the contact impedance of the grounding circuit of each chip, improve the contact consistency of the fixture, make the heat dissipation conditions of each chip more consistent during the high-temperature aging process, effectively reduce the dispersion of test results, improve test accuracy and the effectiveness of aging screening, and significantly improve the test consistency between chips. The conductive compensation layer used in this invention is a thin sheet that is inexpensive and simple in structure, and can be disassembled and replaced independently of the base plate. By transferring the wear and tear of easily worn parts on the base plate to the conductive compensation layer, the service life of the base plate is significantly extended. When the conductive compensation layer deteriorates due to long-term use, the contact performance of the clamp can be restored simply by quickly replacing the conductive compensation layer. Moreover, the replacement process does not require recalibrating the positional relationship between the base plate and the elastic clamping components, which greatly reduces spare parts costs and downtime, and can significantly reduce maintenance costs. The plastic deformation of the conductive compensation layer in this invention can automatically adapt to the slight thickness differences between different batches of chips at the microscale, avoiding stress concentration caused by the different chip thicknesses when relying solely on elastic clamping, reducing the risk of chip damage during testing, improving the compatibility of the fixture and the yield of the tested samples, and improving the adaptability to chips of different sizes. The conductive compensation layer in this invention has a simple structure and can be directly laid in the area defined by the positioning marks on the base plate without the need for complex modifications to the existing herringbone clamp, making it easy to promote and apply. Furthermore, through the two-stage loading of pre-clamping force and working clamping force, it can be ensured that the conductive compensation layer does not shift during clamping and subsequent work, without the need for any additional limiting structure. Attached Figure Description

[0019] Figure 1 This is an exploded view of the components of the test fixture for semiconductor laser chips in Example 1; Figure 2 This is a top view of the test fixture for semiconductor laser chips in Example 1; Figure 3 A schematic diagram of the test curve for PI testing of a COC chip at 75°C using a fixture without a conductive compensation layer. Figure 4This is a schematic diagram of the test curves for PI testing of the same batch of COC chips after the conductive compensation layer was applied, performed at 75°C. Detailed Implementation

[0020] Example 1: See Figure 1 The present invention discloses a test fixture for semiconductor laser chips, comprising a base plate 1 and a cover plate 2. The base plate 1 is an integrally elongated metal plate made of stainless steel or aluminum alloy. The upper surface of the base plate 1 has multiple chip-bearing areas for supporting the chip 100 to be tested. The cover plate 2 is disposed above the base plate 1 and detachably connected to the base plate 1. An elastic clamping assembly for pressing and positioning the chip 100 to be tested is provided between the cover plate 2 and the base plate 1. The test fixture includes at least one replaceable conductive compensation layer 3, which is laid on the base plate 1 and located between the base plate 1 and the chip under test 100. The conductive compensation layer 3 is made of a ductile conductive and thermally conductive material. The conductive compensation layer 3 is configured to undergo plastic deformation when the cover plate 2 presses the chip under test 100 to compensate for the micro gap between the base plate 1 and the chip under test, so that the chip under test 100 forms an electrical connection and thermal conductive contact with the base plate 1 through the conductive compensation layer 3.

[0021] In this embodiment of the invention, the conductive compensation layer 3 is a metal sheet, and the material of the metal sheet is any one of pure tin, tin alloy, indium, indium alloy, silver, or silver alloy. The thickness of the conductive compensation layer 3 is 0.03 mm to 0.5 mm. The conductive compensation layer 3 is a metal sheet without adhesive layer, and the conductive compensation layer is fixed to the base plate 1 by the clamping force between the cover plate 2 and the base plate 1.

[0022] In this embodiment, the conductive compensation layer 3 is specifically a tin sheet. The tin sheet utilizes the excellent ductility, conductivity, and thermal conductivity of tin material, allowing it to undergo plastic deformation under compression to adhere tightly to the microstructure of the upper surface of the base plate 1. The thickness of the tin sheet is 0.05 mm. In other embodiments, the conductive compensation layer 3 can also be made of other thermally and electrically conductive materials with good ductility, such as tin alloy sheets, indium sheets, or silver sheets. The thickness of the conductive compensation layer 3 can be selected within the range of 0.03 mm to 0.5 mm, preferably within the range of 0.05 mm to 0.15 mm. When the thickness is less than 0.03 mm, the range of micro-gaps that can be compensated is insufficient; when the thickness is greater than 0.5 mm, the thermal and electrical conduction paths of the conductive compensation layer 3 itself will become significantly longer, increasing thermal resistance and contact resistance, thus affecting the stability of the test signal.

[0023] In this embodiment of the invention, the base plate 1 is provided with positioning marks for indicating the placement range of the conductive compensation layer 3. The conductive compensation layer 3 covers the base plate according to the positioning marks, and the outer contour of the conductive compensation layer 3 matches the range defined by the positioning marks, so that multiple chips 100 to be tested can contact the same conductive compensation layer at the same time.

[0024] The positioning marks set on the base plate 1 can be formed by laser marking, screen printing, etching or mechanical engraving, etc. This embodiment does not limit the specific formation method of the positioning marks. The area defined by the positioning marks can be slightly larger than the outer size of the conductive compensation layer 3, based on matching the range defined by the positioning marks, so that the operator can quickly and accurately lay the conductive compensation layer 3 in the correct position, ensuring that the conductive compensation layer 3 replaced in different times has the same or approximately the same coverage area on the base plate 1, thereby ensuring the consistency of the clamping force distribution of the fixture after multiple replacements.

[0025] The conductive compensation layer 3 is configured as a replaceable component; after a test or a batch of tests is completed, the conductive compensation layer that has undergone permanent plastic deformation is removed and replaced with a new conductive compensation layer.

[0026] In an embodiment of the present invention, an elastic clamping assembly is disposed between the cover plate 2 and the base plate 1. The elastic clamping assembly is used to press and position each semiconductor laser chip on the base plate 1. The elastic clamping assembly includes, from bottom to top, a scratch-resistant steel sheet layer 4, a positioning steel sheet layer 5, a spring sheet layer 6, and a feather pressing sheet layer 7 stacked on top of the conductive compensation layer 3. The spring sheet layer 6 includes a plurality of elastic claws 61 corresponding one-to-one with each chip 100 to be tested on the chip carrying area. The ends of the elastic claws 61 press against the chip 100 to be tested. Chip placement grooves 41 are provided on both sides of the scratch-resistant steel sheet layer 4. The chip placement grooves 41 cooperate with the base plate 1 to form a chip carrying area. The positioning steel sheet layer 5 is provided with positioning grooves 51 corresponding to the elastic claws 61. The feather pressing sheet layer 7 includes a plurality of comb-shaped pressing sheets 71. The comb-shaped pressing sheets are used to apply uniform downward pressure to the elastic claws 61. The cover plate 2 is disposed above the base plate 1. The cover plate 2 is detachably connected to the base plate 1 by a plurality of fasteners. In this embodiment, the fastener is a bolt, which is symmetrically arranged at both ends of the cover plate 2, and the bottom plate 1 is provided with threaded holes that mate with the bolts.

[0027] In an embodiment of the present invention, a method for using a semiconductor laser chip test fixture is also provided. The method is implemented based on the above-described semiconductor laser chip test fixture and includes the following steps: S1. Lay the conductive compensation layer on the upper surface of the base plate and position the conductive compensation layer within the area defined by the positioning marks on the base plate. In this embodiment, the conductive compensation layer is a 0.05mm thick tin sheet. The size of the tin sheet is basically matched with the area defined by the positioning marks. When laying, the tin sheet covers the base plate to ensure that the chips to be tested at multiple stations on the base plate can contact the tin sheet and that the clamping force on each chip to be tested is consistent. S2. Install each layer of the elastic clamping assembly in sequence; S3. Place multiple chips to be tested in the chip carrier area and on the upper surface of the conductive compensation layer, so that each chip to be tested is in contact with the conductive compensation layer and the lower surface of the chip to be tested is above the conductive compensation layer. S4. Place the cover plate on top of the base plate and connect the cover plate to the base plate with fasteners. Apply a vertical pre-compression force to the conductive compensation layer to initially stabilize it. Then apply a vertical working compression force to cause the conductive compensation layer to undergo plastic deformation under the compression force. The upper and lower surfaces of the conductive compensation layer form static friction contact with the chip under test and the base plate, respectively. The conductive compensation layer, which undergoes plastic deformation, compensates for the micro gap between the chip under test and the base plate, so that the chip under test and the base plate form a consistent electrical connection and thermal conduction contact.

[0028] In this embodiment of the invention, the working clamping force is configured such that the maximum static friction between the conductive compensation layer and the base plate and the chip under test is greater than 1.5 times the maximum horizontal disturbance force that the fixture experiences during operation. This ensures that the conductive compensation layer does not shift during clamping and subsequent testing without any additional limiting structure.

[0029] When the conductive compensation layer deteriorates due to use and affects contact consistency, the conductive compensation layer can be replaced. The replacement process includes the following steps: Step a1: Use a torque tool to loosen the fasteners one by one in a diagonal sequence, releasing the preload between the cover plate and the base plate one by one to prevent the cover plate from tilting and jamming due to uneven force; after the fasteners are completely removed, lift the cover plate vertically upwards and smoothly to detach the cover plate from the base plate. Step a2: Remove each layer of the elastic clamping assembly in sequence to separate the elastic clamping assembly from the base plate. In this embodiment, the disassembly order of each layer from top to bottom is: feather pressing sheet layer, spring sheet layer, positioning steel sheet layer, and anti-scratch steel sheet layer. Each pressing sheet is placed flat on a clean table and isolated with clean paper to avoid collision between pressing sheets and deformation. Step a3: Remove the old conductive compensation layer that has undergone plastic deformation. In this embodiment, anti-static tweezers are used to hold the peeled-off area of ​​the conductive compensation layer edge and vertically and steadily remove the old conductive compensation layer, placing it into the waste collection box. Since the conductive compensation layer has undergone permanent plastic deformation during use, its surface has been solidified to form a microstructure that adheres to the chip under test, so the old conductive compensation layer cannot be reused. In this embodiment, the thickness of the conductive compensation layer is only 0.05mm, and there is no residual adhesive layer. Therefore, the removal process does not require any cleaning or chemical treatment and will not damage the surface of the substrate. Step a4: Lay the new conductive compensation layer within the area defined by the positioning marks on the base plate, ensuring that its coverage and placement are consistent with the previous laying. Step a5: Reassemble the elastic clamping assembly and cover plate. Reassemble the anti-scratch steel sheet layer, positioning steel sheet layer, spring sheet layer, feather pressure sheet layer and cover plate in the reverse order of disassembly, and finally tighten them with fasteners.

[0030] To verify the effectiveness of the present invention, this embodiment provides a set of comparative experiments. In the comparative experiments, the same batch of semiconductor laser chips were subjected to high-temperature power aging tests at an ambient temperature of 75°C. The PI characteristic curve test has high sensitivity to the contact consistency between the chip and the fixture and the heat dissipation conditions. The control group used a conventional herringbone fixture without a conductive compensation layer for testing, and the results are as follows. Figure 3 As shown; the example group used the fixture with a conductive compensation layer from Example 1 of the present invention for testing, and the results are as follows. Figure 4 As shown.

[0031] Depend on Figure 3 It is evident that the PI curves of each chip in the comparison group exhibit significant dispersion at high temperatures, with some curves showing power saturation or power dips due to inconsistent contact and poor heat dissipation. Figure 4 As can be seen, the PI curves of the same batch of chips in the example group exhibit good consistency at high temperatures, with the curves basically overlapping, and there is no power saturation or dip phenomenon caused by heat dissipation issues. The results show that after adding the conductive compensation layer, the contact consistency and heat dissipation consistency of the same batch of chips at high temperatures are significantly improved, which improves the reliability of testing and the yield of aging screening; at the same time, since the conductive compensation layer is easy to replace, the wear and replacement cost of the substrate is significantly reduced.

[0032] Example 2: This embodiment is basically the same as Embodiment 1, except that the conductive compensation layer is replaced by an indium sheet instead of a tin sheet, and the thickness of the indium sheet is 0.10 mm. Indium material has better ductility and lower hardness than tin, and can produce sufficient plastic deformation under smaller clamping forces. Therefore, the fixture provided in this embodiment has good compatibility in working conditions where the lower surface of the chip is relatively fragile and sensitive to clamping forces.

[0033] Example 3: This embodiment is basically the same as Embodiment 1, except that the conductive compensation layer is replaced by a silver sheet instead of a tin sheet, and the thickness of the silver sheet is 0.08 mm. Silver has better electrical and thermal conductivity than tin. Therefore, in situations where the chip operates at high power and the requirements for heat dissipation and conductivity of the fixture are high, the fixture provided in this embodiment has better testing performance.

[0034] The semiconductor laser chip test fixture and its usage method provided in this invention add a plastically deformable conductive compensation layer between the base plate and the semiconductor laser chip. Under clamping force, the conductive compensation layer undergoes plastic deformation, adaptively filling the microscopic gap between the upper surface of the base plate and the lower surface of the chip at a microscale, ensuring uniform and reliable contact between each chip and the base plate. Simultaneously, the cost of the conductive compensation layer is significantly lower than that of the base plate, and replacement can be completed without recalibrating other parts of the fixture, greatly reducing maintenance costs and downtime. The semiconductor laser chip test fixture provided by this invention has the advantages of simple structure and ease of implementation, and can be widely applied in the testing of semiconductor laser chips and other devices requiring improved contact consistency between the chip and the fixture.

[0035] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0036] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A test fixture for semiconductor laser chips, comprising a base plate and a cover plate, wherein the upper surface of the base plate has a plurality of chip-carrying areas for carrying the chip to be tested, the cover plate is disposed above the base plate and detachably connected to the base plate, and an elastic clamping assembly for pressing and positioning the chip to be tested is disposed between the cover plate and the base plate, characterized in that: The test fixture includes at least one replaceable conductive compensation layer, which is laid on the base plate and located between the base plate and the chip under test. The conductive compensation layer is made of a ductile, conductive, and thermally conductive material and is configured to undergo plastic deformation when the cover plate is pressed against the chip under test by an elastic clamping assembly. This deformation compensates for the microscopic gap between the base plate and the chip under test, allowing the chip under test to form an electrical connection and thermal conductive contact with the base plate through the conductive compensation layer.

2. The test fixture for semiconductor laser chips according to claim 1, characterized in that: The conductive compensation layer is a metal sheet, and the material of the metal sheet is any one of pure tin, tin alloy, indium, indium alloy, silver, or silver alloy.

3. A test fixture for semiconductor laser chips according to claim 1, characterized in that: The thickness of the conductive compensation layer is 0.03 mm to 0.5 mm.

4. A test fixture for semiconductor laser chips according to claim 2, characterized in that: The conductive compensation layer is a non-adhesive metal sheet, and the conductive compensation layer is fixed to the base plate by the clamping force between the cover plate and the base plate.

5. A test fixture for semiconductor laser chips according to claim 1, characterized in that: The base plate is provided with positioning marks for indicating the placement range of the conductive compensation layer. The conductive compensation layer covers the base plate according to the positioning marks, and the outer contour of the conductive compensation layer matches the range defined by the positioning marks, so that multiple chips under test can contact the same conductive compensation layer at the same time.

6. A test fixture for semiconductor laser chips according to claim 1, characterized in that: The conductive compensation layer is configured as a replaceable component; after one or a batch of tests are completed, the conductive compensation layer that has undergone permanent plastic deformation is removed and replaced with a new conductive compensation layer.

7. A test fixture for semiconductor laser chips according to claim 1, characterized in that: The elastic clamping assembly includes, from bottom to top, a scratch-resistant steel sheet layer, a positioning steel sheet layer, a spring sheet layer, and a feather pressure sheet layer stacked on top of the conductive compensation layer; the spring sheet layer includes multiple elastic pressure claws corresponding one-to-one with each chip to be tested on the chip carrier area, and the ends of the elastic pressure claws abut against the chip to be tested; chip placement grooves are provided on both sides of the scratch-resistant steel sheet layer, and the chip placement grooves cooperate with the base plate to form the chip carrier area; the positioning steel sheet layer has positioning grooves corresponding to the elastic pressure claws; the feather pressure sheet layer includes multiple comb-shaped pressure plates, and the comb-shaped pressure plates are used to apply uniform downward pressure to the elastic pressure claws; the cover plate is detachably connected to the base plate by fasteners, and the fasteners are distributed at both ends of the cover plate.

8. A method of using a semiconductor laser chip test fixture, said method being implemented based on the semiconductor laser chip test fixture according to any one of claims 1 to 7, characterized in that, Includes the following steps: Step S1: Lay the conductive compensation layer on the upper surface of the base plate; Step S2: Install each layer of the elastic clamping assembly sequentially; Step S3: Place multiple chips to be tested in the chip carrier area and on the upper surface of the conductive compensation layer; Step S4: Cover the cover plate on top of the base plate and connect the cover plate to the base plate with fasteners; apply a pre-compression force in the vertical direction to the conductive compensation layer to initially stabilize the conductive compensation layer, and then apply a working compression force in the vertical direction to cause the conductive compensation layer to undergo plastic deformation under the compression force.

9. The method of using the semiconductor laser chip test fixture according to claim 8, characterized in that: The working clamping force is configured such that the maximum static friction between the conductive compensation layer and the base plate and the chip under test is greater than 1.5 times the maximum horizontal disturbance force that the test fixture experiences during operation.

10. The method of using a semiconductor laser chip testing fixture according to claim 8, characterized in that: The method also includes a step of replacing the conductive compensation layer: Use a torque tool to loosen the fasteners one by one in a diagonal sequence to detach the cover plate from the base plate; Remove each layer of the elastic clamping assembly in sequence to separate the elastic clamping assembly from the base plate; Remove the old conductive compensation layer that has undergone plastic deformation; Lay the new conductive compensation layer within the area defined by the positioning marks on the base plate; Reassemble the elastic clamping assembly and cover plate.

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