CN111812482A - Reliability test system for laser chips - Google Patents

Abstract

The invention discloses a reliability test system for a laser chip, which comprises a substrate, a carrier plate and a first PCB, wherein a chip groove is formed in the carrier plate, a chip probe is arranged on the first PCB, a TEC is arranged between the substrate and the carrier plate, a heat insulation plate is arranged between the substrate and the first PCB, and a heat insulation through groove is formed in the heat insulation plate; the second PCB is provided with a connecting contact, a testing contact, a welding contact and a power supply contact, the first PCB and the base plate are arranged on the base plate through a fixing screw, the base plate is also provided with a limiting rod, a limiting spring is sleeved on the limiting rod, a limiting hole for the limiting rod to be embedded in is formed in the base plate, a strip-shaped guide hole is communicated with the base plate on one side of the limiting hole, and the strip-shaped guide hole is positioned on one side, close to the chip, of the base plate; the welding contact is positioned on the bottom surface of the second PCB, and a welding through hole corresponding to the welding contact is formed in the bottom surface of the substrate. The invention can not only improve the temperature control precision, but also test a plurality of chips at a time, thereby effectively improving the test efficiency.

Description

Reliability test system for laser chips

technical field

The invention relates to a reliability testing system for laser chips, belonging to the technical field of chip processing.

Background technique

Chip burn-in is an electrical stress test method that uses voltage and high temperature to accelerate electrical failure of the device, where the burn-in process essentially simulates running the entire life of the chip because the electrical excitation applied during burn-in reflects the worst-case scenario of chip operation .

The burn-in test can be used as a device reliability test or as a production window to find the early failure of the device. Generally, the device used for chip burn-in test works together with an external circuit board through a test socket. In the existing burn-in test fixture, The heating source that provides the temperature is far away from the chip, the temperature control accuracy is poor, and only a single chip can be tested at a time, which is very troublesome.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a reliability test system for laser chips, which can not only improve the temperature control accuracy, but also test multiple chips at a time, thereby effectively improving the test efficiency.

In order to achieve the above object, the technical solution adopted in the present invention is: a reliability testing system for a laser chip, comprising a substrate, a carrier board mounted on the substrate, and a first PCB mounted on the carrier board, and the carrier board opens There are chip grooves for chips to be embedded in, the first PCB has chip probes corresponding to the chip grooves, a number of TECs are installed between the substrate and the carrier board, and the TECs are located directly below the chip grooves, and the substrate A heat shield is installed between the first PCB and the heat shield, and the heat shield is provided with a heat shield through slot for embedding the TEC;

The first PCB is mounted on the heat shield, and a second PCB is mounted on the substrate, and the second PCB has connection contacts, test contacts communicating with the connection contacts, soldering contacts and soldering contacts Connected power supply contacts, the first PCB has connection probes corresponding to the connection contacts, the test contacts are used to connect external equipment, and the electricity connection pins of the TEC are welded on the welding contacts;

A backing plate is installed between the first PCB and the heat insulation board. The backing plate is provided with a probe through hole for the chip probe and the connection probe to pass through. The first PCB and the backing plate are installed by a fixing screw. On the base plate, the base plate is also provided with a limit rod, the limit rod is sleeved with a limit spring located between the backing plate and the carrier plate, and the backing plate is provided with a limit hole for the limit rod to be embedded in , the backing plate on one side of the limiting hole is also connected with a strip-shaped guide hole, and the strip-shaped guide hole is located on the side of the backing plate close to the chip;

The soldering contacts are located on the bottom surface of the second PCB, and the bottom surface of the substrate is provided with soldering through holes corresponding to the soldering contacts.

The further improved scheme in the above technical scheme is as follows:

1. In the above solution, the top surface of the substrate is provided with a mounting groove for the TEC to be embedded.

2. In the above solution, the installation grooves are separated by two, and the carrier plates are arranged in two and are respectively located in the two installation grooves.

3. In the above solution, the number of TECs in one of the slots is four, and two of the chip slots correspond to one TEC.

4. In the above solution, the side edge of the top surface of the base plate is provided with a heat insulation groove for embedding the heat insulation board, and the installation groove is opened at the bottom of the heat insulation groove.

5. In the above solution, arc openings are opened at the corners of the heat insulating grooves.

6. In the above solution, the side edge of the top surface of the heat insulation board is provided with a stepped groove for embedding the carrier board.

7. In the above solution, a positioning rod is provided on the base plate, and positioning holes for embedding the positioning rod are formed on the heat insulation plate, the carrier plate and the backing plate.

Due to the application of the above-mentioned technical solutions, the present invention has the following advantages compared with the prior art:

1. In the reliability testing system for laser chips of the present invention, several TECs are installed between the substrate and the carrier board, and the TECs are located directly below the chip groove. And install the carrier board for placing the chip on the TEC, and directly place the chip on the TEC used for heating and temperature control, the TEC can directly heat the chip, not only fast heating, high efficiency, but also high temperature control accuracy, each The test results of the chip are less affected by temperature fluctuations; a heat shield is installed between the substrate and the first PCB, and the heat shield has a heat shield through slot for the TEC to be embedded. In the thermal insulation channel of the active thermal insulation board, on the one hand, the heat generated by the TEC can be prevented from dissipating to the surroundings by the thermal insulation board, and the heating efficiency can be improved. It is limited to the chip slot of the carrier board, which makes the temperature control accuracy of the TEC higher, and reduces the temperature fluctuation range caused by energy dissipation to the surroundings, further reducing the impact of temperature fluctuation on the test accuracy.

2. In the reliability testing system for laser chips of the present invention, the first PCB is installed on the heat insulation board, and a second PCB is installed on the substrate, and the second PCB has connection contacts and is connected with the connection contacts. Contacts, soldering contacts, and power supply contacts communicating with the soldering contacts, the first PCB has connection probes corresponding to the connection contacts, the test contacts are used to connect external devices, and the connection of the TEC The electrical pins are welded on the welding contacts. Since the TEC component requires an external power supply, the PCB not only needs to be connected to the TEC for integrated power supply, but also needs to be connected to the chip during use, which is convenient for the staff to test the chip. However, when disassembling and installing the chip , Need to move to release the contact between the PCB probe and the chip. On the one hand, the PCB connected to the chip is required to be able to move relative to the substrate. On the other hand, the PCB fixed to the TEC must not be moved to avoid affecting the heating and temperature control function of the TEC. , therefore, by modularizing the PCB into a first PCB with chip probes and connection probes and a second PCB with connection contacts, test contacts, solder contacts and power supply contacts, the use of movable The first PCB of the device is connected and disconnected from the chip, and then the chip is tested by means of the connection between the first PCB and the second PCB, so as to meet the multiple requirements of power supply, testing, disassembly and assembly, which is very convenient.

3. In the reliability testing system for laser chips of the present invention, the first PCB and the backing plate are mounted on the base plate through a fixing screw, and the base plate is also provided with a limit rod. The limit spring between the plates, the backing plate has a limit hole for the limit rod to be embedded, and the backing plate on one side of the limit hole is also connected with a strip guide hole, and the strip guide hole Located on the side of the backing plate close to the chip, the first PCB can be stably communicated with the chip through the setting of the fixing screws, and the limit spring still has a certain thickness after being compressed, so that the limit spring in the compressed state isolates the carrier board And the backing plate to form a light gap, which is convenient for the laser chip to complete the photoelectric test. At the same time, after the fixing screw is loosened, the limit spring can automatically push up the backing plate, so that the chip probe of the first PCB can be separated from the chip, which is convenient for the staff to operate. The chip in the chip slot, and the limit rod passing through the limit hole can slide along the strip guide hole communicated with the limit hole, so that the backing plate and the first PCB board are far away from the chip slot and avoid the chip The probes, the pad and the first PCB affect the disassembly and assembly of the chip.

4. In the reliability testing system for laser chips of the present invention, the welding contacts are located on the bottom surface of the second PCB, and the bottom surface of the substrate is provided with welding through holes corresponding to the welding contacts. Therefore, in order to avoid the problem of poor quality during the TEC welding process, it is difficult to maintain each TEC in the same reference plane after the TEC welding is completed, resulting in the carrier board mounted on multiple TECs and the There are gaps of different sizes between the TECs, which are difficult to fit completely, which will not only affect the installation of the carrier board, but also cause the chips corresponding to different TECs to be in different temperature ranges due to the existence of gaps of different sizes, and the test accuracy of a single chip is poor. , the test results of the same batch of chips are quite different, which affects the use of the fixture. Therefore, the soldered through holes on the substrate expose the soldered contacts, and the heat insulation board, the carrier board and the TEC are assembled in advance and installed into the heat insulation board. In the tank, the staff can not only directly realize the welding of the power-connecting pins and the welding contacts, but also avoid the deviation of the TEC due to the welding work, thereby ensuring the uniformity of the TEC heating and temperature control.

5. The reliability testing system for laser chips of the present invention has two mounting slots spaced apart, two of the carrier boards are arranged in the two mounting slots, and the number of TECs in one of the mounting slots is four. Each of the two chip slots corresponds to one TEC. By setting multiple TECs in the mounting slot, the heating efficiency and density of the heat source are further increased, so that more chip slots can be opened on the carrier board, and the first The cooperation of the PCB and the second PCB integrates the connection and testing of each chip, thereby improving the testing efficiency of the chip and reducing the testing cost.

Description of drawings

1 is a schematic diagram of the overall structure of the reliability testing system for laser chips according to the present invention;

Accompanying drawing 2 is a partial exploded view of the reliability testing system for laser chips;

Accompanying drawing 3 is the exploded view of A part in accompanying drawing 2;

Accompanying drawing 4 is the partial exploded view of another angle of view of the reliability test system for laser chips;

5 is a schematic diagram of the bottom structure of the reliability testing system for laser chips;

Figure 6 is a schematic diagram of the explosion structure of the backing plate and the first PCB part.

In the above drawings: 1, base plate; 11, limit rod; 12, limit spring; 16, welding through hole; 101, installation groove; 106, positioning rod; 107, positioning hole; 108, heat insulation groove; 109, Arc mouth; 2, carrier board; 201, chip slot; 3, first PCB; 31, chip probe; 32, connection probe; 4, TEC; 41, electrical pin; 5, heat shield; 51 , heat insulation through slot; 501, stepped slot; 6, second PCB; 61, connection contact; 62, test contact; 63, welding contact; 64, power supply contact; 7, backing plate; 71, fixing screw ; 72, limit hole; 73, strip guide hole; 701, probe through hole.

Detailed ways

Embodiment 1: A reliability testing system for laser chips, referring to Figures 1-6, includes a substrate 1, a carrier board 2 mounted on the substrate 1, and a first PCB 3 mounted on the carrier board 2, the carrier board 2 is provided with a chip slot 201 for chip embedding, the first PCB 3 has chip probes 31 corresponding to the chip slot 201, and several TEC4 are installed between the substrate 1 and the carrier board 2, and this TEC4 is located in the chip. Just below the groove 201, a heat insulation board 5 is installed between the substrate 1 and the first PCB 3, and the heat insulation board 5 is provided with a heat insulation through groove 51 for the TEC4 to be embedded;

The first PCB3 is mounted on the heat shield 5, and a second PCB6 is mounted on the substrate 1. The second PCB6 has connection contacts 61, test contacts 62 communicating with the connection contacts 61, and solder contacts. 63 and the power supply contact 63 communicated with the solder contact 63, the first PCB3 has a connection probe 32 corresponding to the connection contact 61, the test contact 62 is used to connect external equipment, the connection of the TEC4 The electrical pins 41 are welded on the welding contacts 63;

A backing plate 7 is installed between the first PCB 3 and the heat insulating plate 5, and the backing plate 7 is provided with a probe through hole 701 for the chip probe 31 and the connection probe 32 to pass through. The first PCB 3 and the pad The plate 7 is mounted on the base plate 1 by a fixing screw 71, and the base plate 1 is also provided with a limit rod 11. The limit rod 11 is sleeved with a limit spring 12 located between the backing plate 7 and the carrier plate 2, so The spacer plate 7 is provided with a limit hole 72 for the limit rod 11 to be embedded in. The spacer plate 7 on one side of the limit hole 72 is also connected with a strip guide hole 73, and the strip guide hole 73 is located in the spacer. The side of the board 7 close to the chip;

The soldering contacts 63 are located on the bottom surface of the second PCB 6 , and soldering through holes 16 corresponding to the soldering contacts 63 are opened on the bottom surface of the substrate 1 .

The top surface of the above-mentioned base plate 1 is provided with installation grooves 101 for TEC4 to be embedded; the above-mentioned installation grooves 101 are spaced apart by two, and the above-mentioned carrier plates 2 are arranged in two and are respectively located in the two installation grooves 101; one TEC4 in the above-mentioned installation groove The number is four, and two of the above-mentioned chip slots 201 correspond to one TEC4.

The side edge of the top surface of the above-mentioned base plate 1 is provided with a heat insulation groove 108 for the heat insulation plate 5 to be embedded in, the above-mentioned installation groove 101 is opened at the bottom of the heat insulation groove 108; the corner of the above-mentioned heat insulation groove 108 is opened with an arc-shaped opening 109 .

The side edge of the top surface of the heat insulating plate 5 is provided with a stepped groove 501 for embedding the carrier plate 2; The positioning hole 107 into which the positioning rod 106 is inserted.

Embodiment 2: A reliability testing system for laser chips, referring to Figures 1-6, includes a substrate 1, a carrier 2 mounted on the substrate 1, and a first PCB 3 mounted on the carrier 2, the carrier 2 is provided with a chip slot 201 for chip embedding, the first PCB 3 has chip probes 31 corresponding to the chip slot 201, and several TEC4 are installed between the substrate 1 and the carrier board 2, and this TEC4 is located in the chip. Just below the groove 201, a heat insulation board 5 is installed between the substrate 1 and the first PCB 3, and the heat insulation board 5 is provided with a heat insulation through groove 51 for the TEC4 to be embedded;

The first PCB3 is mounted on the heat shield 5, and a second PCB6 is mounted on the substrate 1. The second PCB6 has connection contacts 61, test contacts 62 communicating with the connection contacts 61, and solder contacts. 63 and the power supply contact 63 communicated with the solder contact 63, the first PCB3 has a connection probe 32 corresponding to the connection contact 61, the test contact 62 is used to connect external equipment, the connection of the TEC4 The electrical pins 41 are welded on the welding contacts 63;

A backing plate 7 is installed between the first PCB 3 and the heat insulating plate 5, and the backing plate 7 is provided with a probe through hole 701 for the chip probe 31 and the connection probe 32 to pass through. The first PCB 3 and the pad The plate 7 is mounted on the base plate 1 by a fixing screw 71, and the base plate 1 is also provided with a limit rod 11. The limit rod 11 is sleeved with a limit spring 12 located between the backing plate 7 and the carrier plate 2, so The spacer plate 7 is provided with a limit hole 72 for the limit rod 11 to be embedded in. The spacer plate 7 on one side of the limit hole 72 is also connected with a strip guide hole 73, and the strip guide hole 73 is located in the spacer. The side of the board 7 close to the chip;

The soldering contacts 63 are located on the bottom surface of the second PCB 6 , and soldering through holes 16 corresponding to the soldering contacts 63 are opened on the bottom surface of the substrate 1 .

The top surface of the above-mentioned base plate 1 is provided with installation grooves 101 for TEC4 to be embedded; the above-mentioned installation grooves 101 are spaced apart by two, and the above-mentioned carrier plates 2 are arranged in two and are respectively located in the two installation grooves 101; one TEC4 in the above-mentioned installation groove The number is four, and two of the above-mentioned chip slots 201 correspond to one TEC4.

The side edge of the top surface of the above-mentioned base plate 1 is provided with a heat insulation groove 108 for the heat insulation plate 5 to be embedded in, the above-mentioned installation groove 101 is opened at the bottom of the heat insulation groove 108; the corner of the above-mentioned heat insulation groove 108 is opened with an arc-shaped opening 109 The side edge of the top surface of the heat insulating plate 5 is provided with a stepped groove 501 into which the carrier plate 2 is embedded.

When using the above reliability test system for laser chips, by installing a TEC, that is, a semiconductor refrigerator, between the substrate and the PCB, and installing a carrier plate for placing the chip on the TEC, the chip is directly placed in the heating control system. On a warm TEC, the TEC can directly heat the chip, which not only has fast heating speed and high efficiency, but also has high temperature control accuracy. The test results of each chip are less affected by temperature fluctuations; In the heat insulation channel of the hot plate, on the one hand, the heat generated by the TEC can be prevented from dissipating to the surroundings by the heat insulation plate, and the heating efficiency is improved. At the chip slot of the board, the temperature control accuracy of the TEC is higher, and the temperature fluctuation range caused by energy dissipation to the surroundings is reduced, and the impact of temperature fluctuation on the test accuracy is further reduced.

In addition, since the TEC component requires an external power supply, the PCB not only needs to be connected to the TEC for integrated power supply, but also needs to be connected to the chip during use, which is convenient for the staff to test the chip. However, when disassembling and installing the chip, it is necessary to remove the PCB probe and The contact of the chip, on the one hand, requires the PCB connected to the chip to be able to move relative to the substrate, on the other hand, requires that the PCB fixed to the TEC cannot move, so as to avoid affecting the heating and temperature control function of the TEC. Therefore, by modularizing the PCB Divided into a first PCB with chip probes and connection probes and a second PCB with connection contacts, test contacts, solder contacts and power supply contacts, so that the movable first PCB is used to realize the connection with the chip It is very convenient to connect and disconnect, and then use the connection of the first PCB and the second PCB to realize the test of the chip, so as to meet the multiple requirements of power supply, testing, disassembly and assembly.

In addition, through the setting of the fixing screws, the first PCB can be stably communicated with the chip, and the limit spring still has a certain thickness after being compressed, so that the carrier plate and the backing plate are separated by the limit spring in the compressed state to form a light travel gap. , which is convenient for the laser chip to complete the photoelectric test. At the same time, after the fixing screw is loosened, the limit spring can automatically push up the backing plate, so that the chip probe of the first PCB can be separated from the chip, which is convenient for the staff to operate the chip in the chip slot, and , the limit rod passing through the limit hole can slide along the bar-shaped guide hole connected with the limit hole, so as to keep the backing plate and the first PCB board away from the chip groove, and avoid the chip probe, the backing plate and the first PCB board. A PCB affects the disassembly and assembly of the chip

In addition, since it is necessary to solder the power pins of the TEC to the soldering contacts of the second PCB, in order to avoid the problem of poor quality during the TEC soldering process, it is difficult for each TEC to maintain the same reference after the TEC soldering is completed. In the surface, there are gaps of different sizes between the carrier board and the TEC installed on multiple TECs, which is difficult to fit completely. The chips are in different temperature ranges, the test accuracy of a single chip is poor, and the test results of the same batch of chips are quite different, which affects the use of the fixture. Therefore, the soldering through holes on the substrate expose the soldering contacts, and the heat shield , The carrier board and the TEC are assembled into one, and installed in the heat insulation groove, the staff can not only directly realize the welding of the power connection pins and the welding contacts, but also avoid the TEC from offset due to the welding work, so as to ensure the heating of the TEC. Uniformity of temperature control.

In addition, through the arrangement of multiple TECs in the mounting slot, the heating efficiency and density of the heat source are further increased, so that more chip slots can be opened on the carrier board, and the cooperation of the first PCB and the second PCB can be used to integrate each chip. Connect and test, thereby improving the test efficiency of the chip and reducing the test cost.

The above-mentioned embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement them accordingly, and cannot limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be included within the protection scope of the present invention.

Claims (8)

1. A reliability testing system for a laser chip, characterized in that it comprises a substrate (1), a carrier (2) mounted on the substrate (1), and a first PCB (3) mounted on the carrier (2). ), the carrier board (2) is provided with chip grooves (201) for chip embedding, the first PCB (3) has chip probes (31) corresponding to the chip grooves (201), and the substrate A number of TECs (4) are installed between (1) and the carrier board (2), the TECs (4) are located just below the chip slot (201), and between the substrate (1) and the first PCB (3) A heat insulation board (5) is installed, and a heat insulation through groove (51) for embedding the TEC (4) is opened in the heat insulation board (5); The first PCB (3) is mounted on the heat insulation board (5), and a second PCB (6) is mounted on the base plate (1), and the second PCB (6) is provided with connection contacts (61), A test contact (62) communicating with the connecting contact (61), a soldering contact (63) and a power supplying contact (63) communicating with the soldering contact (63), the first PCB (3) has a The connection probes (32) corresponding to the connection contacts (61), the test contacts (62) are used to connect external devices, and the electrical connection pins (41) of the TEC (4) are welded to the welding contacts (63) )superior; A backing plate (7) is installed between the first PCB (3) and the heat insulating plate (5), and the backing plate (7) is provided with a passage for the chip probe (31) and the connection probe (32) to pass through. The probe through hole (701), the first PCB (3) and the backing plate (7) are mounted on the base plate (1) through a fixing screw (71), and the base plate (1) is further provided with a limit rod ( 11), the limit rod (11) is covered with a limit spring (12) located between the backing plate (7) and the carrier plate (2), and the backing plate (7) is provided with a limit rod ( 11) The embedded limit hole (72), the backing plate (7) on one side of the limit hole (72) is also connected with a strip guide hole (73), and the strip guide hole (73) is located in the pad. The side of the board (7) close to the chip; The soldering contacts (63) are located on the bottom surface of the second PCB (6), and soldering through holes (16) corresponding to the soldering contacts (63) are opened on the bottom surface of the substrate (1). 2 . The reliability testing system for laser chips according to claim 1 , wherein a mounting groove ( 101 ) for embedding the TEC ( 4 ) is formed on the top surface of the substrate ( 1 ). 3 . 3. The reliability testing system for laser chips according to claim 2, characterized in that: the mounting grooves (101) are separated by two, and the carrier boards (2) are arranged in two and are respectively located in the two mounting grooves (101). in each mounting slot (101). 4 . The reliability testing system for laser chips according to claim 3 , wherein the number of TECs ( 4 ) in one said slot is four, and two of said chip slots ( 201 ) are connected to one TEC ( 4 . 4 . 4) correspond. 5 . The reliability testing system for laser chips according to claim 2 , wherein a heat insulating groove ( 108 ) into which the heat insulating plate ( 5 ) is embedded is opened at the side edge of the top surface of the substrate ( 1 ). 6 . , the installation groove (101) is opened at the bottom of the heat insulation groove (108). 6 . The reliability testing system for laser chips according to claim 5 , wherein an arc-shaped opening ( 109 ) is opened at the corner of the heat insulating groove ( 108 ). 7 . 7 . The reliability testing system for laser chips according to claim 1 , wherein a stepped groove ( 501 ) into which the carrier board ( 2 ) is embedded is opened at the side edge of the top surface of the heat shield ( 5 ). 8 . . 8. The reliability testing system for laser chips according to claim 1, characterized in that: the substrate (1) is provided with a positioning rod (106), the heat insulation plate (5), the carrier plate (2) A positioning hole (107) into which the positioning rod (106) is embedded is opened on the backing plate (7).

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