Clamp for wafer aging test

Abstract

The invention discloses a clamp for a wafer aging test. The clamp comprises an upper needle clamping seat, a lower chuck and a locking device, the lower chuck is fixed with the upper needle clamping seat through a locking device, and the upper needle clamping seat and the lower chuck define a wafer accommodating cavity for introducing protective gas; the lower chuck is provided with an air inlet channel and an air outlet channel; the gas inlet channel is communicated with the wafer accommodating cavity and is used for introducing protective gas into the wafer accommodating cavity; the upper needle clamping seat is provided with a test unit used for being in contact with a wafer; the lower chuck comprises a wafer bearing disc and a temperature detection device; the wafer bearing disc is used for bearing a wafer and conducting heat to the wafer; and the temperature detection device is arranged on the wafer bearing disc. According to the invention, the replacement of the captive screw is more convenient and time-saving, the efficiency can be improved, and the accuracy of wafer testing can be improved; in addition, convection replacement can be formed, and it is guaranteed that the testing environment is full of protective gas.

Description

Technical Field

[0001] The present invention relates to the field of wafer aging test tooling, and particularly to a fixture for wafer aging test. Background Art

[0002] As a typical representative of the third-generation wide bandgap semiconductor materials, SiC (silicon carbide) has characteristics such as high critical breakdown field strength, high thermal conductivity, high electron saturation drift velocity, large bandgap width, and strong radiation resistance. It has been widely used in the new energy field. SiC wafers using SiC are generally not of high yield due to the existing manufacturing process level, and only through the traditional wafer test probes for electrical performance testing to screen, it is impossible to effectively eliminate the early failures of the devices themselves. SiC wafers must be effectively eliminated after high-temperature and electrical stress aging, so aging tests need to be carried out in a wafer aging test fixture.

[0003] The existing wafer aging test fixtures generally include an upper needle socket and a lower chuck. The lower chuck is fixed to the upper needle socket through a locking device. The locking device includes a locking nut and a non-loosening screw. The locking nut is arranged on the lower chuck. The non-loosening screw is installed on the upper needle socket and cooperates with the locking nut to lock the upper needle socket and the lower chuck. However, when the non-loosening screw needs to be replaced, the upper needle socket needs to be disassembled to take out the non-loosening screw, and after installing a new non-loosening screw, the upper needle socket still needs to be assembled. Since the disassembly and assembly of the upper needle socket are relatively cumbersome and time-consuming, the replacement of the non-loosening screw is rather inconvenient and time-consuming, and it fails to meet the high requirements of the industry. Moreover, the existing wafer aging test fixtures are also prone to the problem of low wafer test accuracy and cannot meet the high requirements of the industry. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a fixture for wafer aging test, which makes the replacement of the non-loosening screw more convenient and time-saving, can save time, improve efficiency, and can improve the accuracy of wafer testing.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A fixture for wafer aging test, comprising an upper pin socket, a lower chuck and a locking device; the lower chuck is fixed to the upper pin socket through the locking device, and the upper pin socket and the lower chuck enclose a wafer accommodating cavity for introducing a protective gas; an air inlet channel and an air outlet channel are arranged on the lower chuck; the air inlet channel is communicated with the wafer accommodating cavity and is used for supplying the protective gas into the wafer accommodating cavity; the air outlet channel is communicated with the wafer accommodating cavity and is used for discharging the gas; the upper pin socket is provided with a test unit for contacting the wafer; the lower chuck comprises a wafer carrier and a temperature detection device; the wafer carrier is used for carrying the wafer and conducting heat to the wafer; the temperature detection device is arranged on the wafer carrier and is used for detecting the temperature; the locking device comprises a locking nut and a locking component; the locking nut is arranged on the lower chuck; the locking component is arranged on the upper pin socket and comprises a mounting seat, a connecting component and a spring; a positioning groove is arranged on the upper pin socket, the mounting seat is embedded in the positioning groove and is fixed to the upper pin socket in a detachable manner; the connecting component penetrates through the mounting seat, and the spring abuts between the mounting seat and the connecting component; the connecting component comprises a non-loosening screw, the non-loosening screw penetrates through the mounting seat, and the connecting end of the non-loosening screw cooperates with the locking nut; a limiting portion for limiting the connecting end of the non-loosening screw is arranged on the mounting seat.

[0007] The test unit comprises a PCB board and a pin card; the PCB board is provided with a pin card, and a plurality of test probes are arranged on the pin card.

[0008] The upper pin socket comprises an upper main seat body and a pressing plate; the pin card is pressed against the PCB board through the pressing plate; the pressing plate, the PCB board and the upper main seat body are fixed together.

[0009] The temperature detection device comprises a first temperature detection element, a second temperature detection element, a third temperature detection element and a fourth temperature detection element.

[0010] A probe device is arranged on the lower chuck, and the first temperature detection element, the second temperature detection element, the third temperature detection element and the fourth temperature detection element are respectively electrically connected to the PCB board through the probe device.

[0011] The locking device comprises a plurality of locking components and a plurality of locking nuts respectively corresponding to the plurality of locking components one by one; the plurality of locking components are arranged on the upper pin socket in a circumferential arrangement; the plurality of locking nuts are arranged on the lower chuck in a circumferential arrangement.

[0012] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0013] A fixture for wafer aging test provided by the present invention fixes the lower chuck to the upper pin socket through a locking device. The upper pin socket and the lower chuck enclose a wafer accommodating cavity for introducing a protective gas. The locking device is a combination of a locking nut and a locking component, and the locking component is a combination of a mounting seat, a connecting component and a spring. When it is necessary to replace the non-loosening screw, the locking component can be disassembled integrally for replacement, so that the non-loosening screw can be replaced without disassembling and assembling the upper pin socket, which can save the disassembly and assembly steps of the upper pin socket, thus greatly saving time, making the replacement of the non-loosening screw more convenient and time-saving, and improving the efficiency. Moreover, the upper pin socket and the lower chuck enclose a wafer accommodating cavity for introducing a protective gas, and an air inlet channel and an air outlet channel are arranged on the lower chuck. At the same time, a test unit is arranged on the upper pin socket, and the lower chuck is provided with a temperature detection device, which can improve the accuracy of wafer testing. In addition, by reasonably arranging the air inlet channel and the air outlet channel, a convection replacement can be formed, so that the air in the wafer accommodating cavity can be replaced by the protective gas, ensuring that the test environment is filled with the protective gas. A layout with one path in the center and three paths evenly distributed around can also be formed to comprehensively and fully detect the heating temperature of the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is an exploded schematic view of the present invention.

[0015] Figure 2 is a structural schematic view of the present invention.

[0016] Figure 3 is Figure 2 a cross-sectional view taken along A1-A1.

[0017] Figure 4 is an exploded schematic view of the locking device.

[0018] Figure 5 is Figure 2 a cross-sectional view taken along A2-A2.

[0019] Figure 6 is a front view of the present invention.

[0020] Figure 7 is Figure 6 a cross-sectional view taken along D-D of

[0021] Figure 8 is Figure 6 an enlarged view at G of

[0022] Figure 9 is Figure 6 a cross-sectional view taken along E-E of

[0023] Figure 10 is another direction schematic view of the present invention.

[0024] Figure 11 It is a schematic structural diagram of the upper needle base.

[0025] Figure 12 It is a schematic structural diagram of the lower chuck.

[0026] Figure 13 It is a front view of the lower chuck.

[0027] Among them, 10, upper needle base; 15, carrier plate; 16, limit plate; 17, first fastening screw; 20, lower chuck; 22, substrate; 30, locking device; 31, locking nut; 33, nut body; 34, second fastening screw; 40, locking component; 41, mounting seat; 43, spring; 44, non-loosening screw; 45, gasket; 50, wafer accommodating cavity; 60, air inlet channel; 61, air inlet; 62, air inlet connecting groove; 63, air inlet connecting hole; 81, first temperature detection element; 82, second temperature detection element; 83, third temperature detection element; 84, fourth temperature detection element; 90, wafer carrier; 111, PCB board; 112, pin card; 113, test probe; 114, pressing plate. Specific embodiments

[0028] Next, in combination with the accompanying drawings and specific embodiments, the present invention will be further described. It should be noted that, on the premise of no conflict, the following-described embodiments or technical features can be arbitrarily combined to form new embodiments.

[0029] Such as Figures 1-13As shown in the figure, a fixture for wafer aging test includes an upper pin socket 10, a lower chuck 20 and a locking device 30; the lower chuck 20 is fixed to the upper pin socket 10 through the locking device 30, and a wafer accommodating cavity 50 for introducing a protective gas is formed between the upper pin socket 10 and the lower chuck 20; an air inlet channel 60 and an air outlet channel are arranged on the lower chuck 20; the air inlet channel 60 is communicated with the wafer accommodating cavity 50 and is used for introducing the protective gas into the wafer accommodating cavity 50; the air outlet channel is communicated with the wafer accommodating cavity 50 and is used for discharging the gas; the upper pin socket 10 is provided with a test unit for contacting the wafer; the lower chuck 20 includes a wafer carrier 90 and a temperature detection device; the wafer carrier 90 is used for carrying the wafer and conducting heat to the wafer; the temperature detection device is arranged on the wafer carrier 90 and is used for detecting the temperature; the locking device 30 includes a locking nut 31 and a locking component 40; the locking nut 31 is arranged on the lower chuck 20; the locking component 40 is arranged on the upper pin socket 10 and includes a mounting seat 41, a connecting component and a spring 43; a positioning groove is arranged on the upper pin socket 10, the mounting seat 41 is embedded in the positioning groove and is fixed to the upper pin socket 10 in a detachable manner; the connecting component is arranged through the mounting seat 41, and the spring 43 abuts between the mounting seat 41 and the connecting component; the connecting component includes a non-loosening screw 44 which is arranged through the mounting seat 41, and the connecting end of the non-loosening screw 44 is matched with the locking nut 31; a limiting portion for limiting the connecting end of the non-loosening screw 44 is arranged on the mounting seat 41.

[0030] During the HTRB / HTGB aging test of the SiC wafer, the wafer to be detected can be placed in the wafer accommodating cavity 50. The wafer in the wafer accommodating cavity 50 is in direct contact with the wafer carrier 90. Heat can be conducted to the wafer through the wafer carrier 90 to uniformly heat the wafer by means of heat conduction, and the heating temperature can be detected by the temperature detection device to obtain accurate wafer heating temperature parameters. The test unit of the upper pin chuck 10 contacts the wafer to test the wafer. During the test, the protective gas can be introduced into the wafer accommodating cavity 50 through the air inlet channel 60, so that the air in the wafer accommodating cavity 50 is discharged from the air outlet channel 70, so that the air in the wafer accommodating cavity 50 is replaced by the protective gas, thereby providing a stable and protected test environment for the wafer and improving the accuracy of wafer detection. When the fixture is damaged or maintained and the non-loosening screw 44 needs to be replaced, the mounting seat 41 can be detached from the upper pin chuck 10, so that the mounting seat 41 and the connecting components thereon together with the spring 43 can be detached from the upper pin chuck 10 as a whole. Then, the mounting seat 41 with the prepared new locking component 40 is embedded in the positioning groove and fixed to the upper pin chuck 10 in a detachable manner, so that the locking component 40 can be fixed to the upper pin chuck 10 as a whole, and the replacement of the non-loosening screw 44 can be completed. Since the mounting seat 41 is provided with a limiting portion, the connecting end of the non-loosening screw 44 can be limited by the limiting portion to prevent the non-loosening screw 44 from detaching from the mounting seat 41. After the new locking component 40 is fixed to the upper pin chuck 10 as a whole, the non-loosening screw 44 is rotated to threadedly engage the connecting end of the non-loosening screw 44 with the locking nut 31 to lock the lower chuck 20 and the upper pin chuck 10 together, which is convenient for the connection between the lower chuck 20 and the upper pin chuck 10. Therefore, a fixture for wafer aging test provided by the present invention encloses a wafer accommodating cavity 50 for introducing a protective gas by the upper pin chuck 10 and the lower chuck 20, and is provided with an air inlet channel 60 and an air outlet channel 70 on the lower chuck 20; at the same time, a test unit 110 is provided on the upper pin chuck 10, and a temperature detection device is used on the lower chuck 20. The heating temperature of the wafer can be detected by the temperature detection device, and the heating temperature of each area can be uniformly controlled according to the temperature value detected by the temperature detection device. During the test, the air in the wafer accommodating cavity 50 is replaced by the protective gas, thereby providing a stable and protected test environment for the wafer. Considering the above situation, the accuracy of wafer test can be significantly improved; on this basis, the locking device 30 is combined with a locking nut 31 and a locking component 40, and at the same time, the locking component 40 is combined with a mounting seat 41, a connecting component and a spring 43, which is convenient for the connection between the lower chuck 20 and the upper pin chuck 10, ensures the reliability of the connection between the lower chuck 20 and the upper pin chuck 10, can effectively prevent the lower chuck 20 and the upper pin chuck 10 from loosening during the test, and ensures the smooth progress of the test process.When it is necessary to replace the non-loosening screw 44, the locking component 40 can be disassembled integrally for replacement, so that the non-loosening screw 44 can be replaced without disassembling and assembling the upper needle base 10, which can save the disassembly and assembly steps of the upper needle base 10, thus greatly saving time, making the replacement of the non-loosening screw 44 more convenient and time-saving, and improving efficiency.

[0031] The test unit includes a PCB board 111; a needle card 112 is arranged on the PCB board 111, and a plurality of test probes 113 are arranged on the needle card 112. After the wafer to be detected is placed in the wafer accommodating cavity 50, the test probes 113 on the needle card 112 are contacted with the wafer, and the electrical leads of each pin of the wafer are led to the contacts on the PCB board 111 for subsequent aging tests.

[0032] Among them, the PCB board 111 and the test probes 113 can respectively adopt various existing PCB boards 111 and test probes 113 on the market, as long as they can be used for testing wafers.

[0033] The upper needle base 10 includes an upper main seat body and a pressing plate 114; the needle card 112 is pressed against the PCB board 111 through the pressing plate 114; the pressing plate 114, the PCB board 111 and the upper main seat body are fixed together. The upper end of the needle card 112 abuts against the lower end of the PCB board 111, and a first annular protrusion is arranged at the upper end of the needle card 112. The pressing plate 114 is in a rotary ring shape and is fixed to the PCB board 111. A second annular protrusion is arranged at the lower end of the pressing plate 114, and the second annular protrusion abuts against the first annular protrusion to facilitate fixing the needle card 112.

[0034] The mounting seat 41 includes a bearing plate 15 and a limiting plate 16; the limiting plate 16 is fixed to the bearing plate 15 in a detachable manner, and the limiting portion is formed on the limiting plate 16. By adopting the bearing plate 15 and the limiting plate 16 for the mounting seat 41 and the limiting plate 16 being detachable, the structure of the mounting seat 41 is more flexible. When the limiting plate 16 is damaged or needs to be adjusted, the limiting plate 16 can be replaced separately, reducing the maintenance cost and facilitating installation and debugging.

[0035] The connecting component further includes a gasket 45 abutted against the non-loosening screw 44, and the other end of the spring 43 abuts against the gasket 45. Through the arrangement of the gasket 45, the contact area between the spring 43 and the non-loosening screw 44 can be increased, so that the elastic force of the spring 43 can be more evenly transmitted to the non-loosening screw 44, avoiding damage to components caused by excessive local stress. At the same time, the gasket 45 can also play a role of isolation and protection, preventing the spring 43 from directly contacting the non-loosening screw 44 to cause wear or corrosion, prolonging the service life of the connecting component 42, and improving the reliability of the connection.

[0036] The mounting base 41 is fixed on the upper needle chuck 10 by the first fastening screw 17. By adopting the above structure, it can be ensured that the mounting base 41 is firmly mounted on the upper needle chuck 10, preventing it from loosening or displacing during use. Moreover, the fixation is simple and reliable, facilitating installation and disassembly. When maintenance of the mounting base 41 is required or the non-loosening screw 44 needs to be replaced, the first fastening screw 17 can be conveniently removed to disassemble the mounting base 41, reducing the maintenance cost and difficulty.

[0037] Both ends of the mounting base 41 are fixed on the upper needle chuck 10 by the first fastening screw 17.

[0038] The limiting plate 16 is circular in shape. The length of the bearing plate 15 is greater than the diameter of the limiting plate 16. The screw hole is installed on the bearing plate 15. Both sides of the limiting plate 16 are fixed on the bearing plate 15 by locking screws. Locking holes for installing the locking screws are provided on both sides of the limiting plate 16. By adopting the above structure, the stability of the fixation between the limiting plate 16 and the bearing plate 15 can be improved.

[0039] The lock nut 31 is fixed on the lower chuck 20 in a detachable manner. When the lock nut 31 is worn, damaged or adjustment is required, the lock nut 31 can be conveniently removed for replacement or repair, improving the maintenance efficiency.

[0040] The lock nut 31 includes a support body and a nut body 33; the nut body 33 is arranged on the support body 32, and the support body 32 is fixed on the lower chuck 20 in a detachable manner by the second fastening screw 34.

[0041] The locking device 30 includes a plurality of locking components 40 and a plurality of lock nuts 31 respectively corresponding to the plurality of locking components 40 one by one; the plurality of locking components 40 are arranged in a circumferential array on the upper needle chuck 10; the plurality of lock nuts 31 are arranged in a circumferential array on the lower chuck 20. By adopting the above structure, the stability of the fixation between the upper needle chuck 10 and the lower chuck 20 can be improved.

[0042] At least two second positioning pins are provided on the upper needle base 10, and at least two pin holes are provided on the lower chuck 20 for the at least two second positioning pins to be respectively inserted in a one-to-one correspondence. During the connection process of the upper needle base 10 and the lower chuck 20, the upper needle base 10 and the lower chuck 20 can be positioned by inserting the respective second positioning pins into the respective pin holes, and then the connection ends of the respective non-loosening screws 44 are threadedly connected to the respective locking nuts 31, so as to realize the connection between the upper needle base 10 and the lower chuck 20. By combining the locking device 30 and the second positioning pins, the alignment accuracy between the upper needle base 10 and the lower chuck 20 is ensured, and at the same time, each non-loosening screw is prevented from being subjected to a lateral force, resulting in premature damage, and it is convenient for the connection between the upper needle base 10 and the lower chuck 20.

[0043] The air inlet channel 60 includes an air inlet 61 and an air inlet connecting groove 62. One end of the air inlet connecting groove 62 is formed as a first end, and the other end is formed as a second end; the first end of the air inlet connecting groove 62 is communicated with the air inlet 61, and the second end is used for communicating with the wafer accommodating cavity 50. During use, the wafer is placed in the wafer accommodating cavity 50 for testing. The protective gas can flow from the air inlet 61 into the air inlet connecting groove 62 and flow through the air inlet connecting groove 62 to the wafer accommodating cavity 50, so as to promote the air in the wafer accommodating cavity 50 to be discharged through the air outlet channel.

[0044] The air inlet channel 60 further includes an air inlet connecting hole 63. The second end of the air inlet connecting groove 62 is communicated with the wafer accommodating cavity 50 through the air inlet connecting hole 63, so that the protective gas flowing into the air inlet connecting groove 62 from the air inlet 61 can flow to the wafer accommodating cavity 50 through the air inlet connecting hole 63.

[0045] The lower chuck 20 further includes a substrate 22. The wafer carrier 90 is fixed on the substrate 22. The locking nut 31 is provided on the substrate 22. The air inlet channel 60 and the air outlet channel are provided on the substrate 22. The wafer carrier 90 is located in the wafer accommodating cavity 50.

[0046] The temperature detection device includes a first temperature detection element 81, a second temperature detection element 82, a third temperature detection element 83, and a fourth temperature detection element 84.

[0047] A two-dimensional code label is provided on the upper needle base 10, which can realize the recording and management of the usage times and durations of key fixture components such as the test probe 113, the locking device 30, the needle card 112, and the temperature detection device, facilitating the timely replacement of key components for fixture life management. The two-dimensional code label is provided on the upper main body.

[0048] Among them, the fixture can be equipped with a heating element to provide heat for the wafer carrier 90 through the heating element, so as to conduct heat to the wafer through the wafer carrier 90 and uniformly heat the wafer by means of heat conduction. Of course, in addition to this, an external heat source can also be used to provide heat for the wafer carrier 90.

[0049] The above embodiments are only the preferred embodiments of the present invention, and the scope of protection of the present invention cannot be limited thereby. Any non-substantial changes and substitutions made by those skilled in the art on the basis of the present invention belong to the scope of protection required by the present invention.

Claims

1. A fixture for wafer aging test, characterized in that: It includes an upper needle base (10), a lower chuck (20) and a locking device (30); the lower chuck (20) is fixed to the upper needle base (10) through the locking device (30), and a wafer accommodating cavity (50) for introducing a protective gas is formed between the upper needle base (10) and the lower chuck (20); an air inlet channel (60) and an air outlet channel are provided on the lower chuck (20); the air inlet channel (60) is communicated with the wafer accommodating cavity (50) and is used for introducing the protective gas into the wafer accommodating cavity (50); the air outlet channel is communicated with the wafer accommodating cavity (50) and is used for discharging the gas; the upper needle base (10) is provided with a test unit for contacting the wafer; the lower chuck (20) includes a wafer carrier (90) and a temperature detection device; the wafer carrier (90) is used for carrying the wafer and conducting heat to the wafer; the temperature detection device is arranged on the wafer carrier (90) and is used for detecting the temperature; the locking device (30) includes a locking nut (31) and a locking member (40); the locking nut (31) is arranged on the lower chuck (20); the locking member (40) is arranged on the upper needle base (10) and includes a mounting seat (41), a connecting member and a spring (43); a positioning groove is provided on the upper needle base (10), the mounting seat (41) is embedded in the positioning groove and is fixed to the upper needle base (10) in a detachable manner; the connecting member is arranged through the mounting seat (41), and the spring (43) abuts between the mounting seat (41) and the connecting member; the connecting member includes a non-loosening screw (44), the non-loosening screw (44) is arranged through the mounting seat (41), and the connecting end of the non-loosening screw (44) cooperates with the locking nut (31); a limiting portion for limiting the connecting end of the non-loosening screw (44) is provided on the mounting seat (41).

2. The fixture for wafer aging test according to claim 1, wherein: The test unit includes a PCB board (111); a needle card (112) is provided on the PCB board (111), and a plurality of test probes (113) are provided on the needle card (112).

3. The fixture for wafer aging test according to claim 2, wherein: The upper needle base (10) includes an upper main seat body and a pressing plate (114); the needle card (112) is pressed against the PCB board (111) through the pressing plate (114); the pressing plate (114), the PCB board (111) and the upper main seat body are fixed together.

4. The fixture for wafer aging test according to claim 1, wherein: The temperature detection device includes a first temperature detection element (81), a second temperature detection element (82), a third temperature detection element (83) and a fourth temperature detection element (84).

5. The fixture for wafer aging test according to claim 4, wherein: A probe device (91) is provided on the lower chuck (20), and the first temperature detection element (81), the second temperature detection element (82), the third temperature detection element (83) and the fourth temperature detection element (84) are electrically connected to the PCB board (111) through the probe device (91) respectively.

6. The fixture for wafer aging test according to claim 1, wherein: The locking device (30) includes a plurality of locking components (40) and a plurality of locking nuts (31) respectively corresponding to the plurality of locking components (40); the plurality of locking components (40) are arranged in a circumferential array on the upper needle chuck (10); the plurality of locking nuts (31) are arranged in a circumferential array on the lower chuck (20).

Images