Clamp for wafer aging test

Abstract

A clamp for wafer aging test relates to the technical field of wafer test equipment, and comprises a clamp probe board card assembly, a clamp chuck assembly and a heating sucker assembly. The clamp probe board card assembly comprises a board card supporting plate, a board card adapter plate, a probe fixing plate and a bolt assembly, the clamp chuck assembly comprises a chuck base, and the heating suction cup assembly sequentially comprises a heating suction cup, a heating suction cup gasket, a heating piece and a heating piece supporting plate from top to bottom. The device is small in size and small in occupied space, in addition, the structure of the device is designed in a modularized mode, operation of testers is facilitated, testing efficiency is improved, and large-batch testing is achieved.

Description

Technical Field

[0001] This utility model relates to the field of wafer testing equipment technology, and in particular to a fixture for wafer aging testing. Background Technology

[0002] A wafer is a silicon wafer used to fabricate silicon semiconductor circuits; its raw material is silicon. High-purity polycrystalline silicon is dissolved, doped with silicon crystal seed crystals, and then slowly pulled out to form a cylindrical single-crystal silicon wafer. After grinding, polishing, and slicing, the silicon crystal ingot forms a silicon wafer. After processes such as photolithography and etching, the wafer needs to undergo testing, one of which is aging testing.

[0003] Wafer aging tests require the wafer to be fixed in a fixture. Existing fixture devices have the following problems: 1. The device has a complex structure, which is inconvenient for testers to operate, has low testing efficiency, and is not suitable for large-scale testing; 2. The device has low reliability and can easily damage wafer devices during aging tests; 3. The device is large in size and occupies a lot of space. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a fixture for wafer aging testing. The device is small in size, which reduces the space occupied. In addition, the modular design of the device structure facilitates operation by testers, improves testing efficiency, and enables large-scale testing.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] A fixture for wafer aging testing, the fixture comprising a fixture probe board assembly, a fixture chuck assembly, and a heated suction cup assembly.

[0007] The fixture probe board assembly includes a board tray, a board adapter plate fixed to the top surface of the board tray, a probe fixing plate fixed to the bottom surface of the board adapter plate, and a number of bolt assemblies. The board tray has a central circular hole, and the probe fixing plate is located within this hole and has a gate / element probe area on it. The gate / element probe area has an array of gate / element probes, and common probes are located on its sides. The top surface of the board adapter plate has an adapter area with an array of adapter contacts. The probe distribution on the probe fixing plate corresponds to the wafer. During aging testing, the probes abut against the wafer, and the test signal is transmitted outward through the probes and the adapter contacts in the adapter area.

[0008] The clamp chuck assembly includes a chuck base with a cavity on the top surface and an inflation connector, an air extraction connector seat, and an inner wire adapter plate on the side. The inflation connector communicates with the cavity. The chuck base has an air extraction channel A, the outer end of which communicates with the air extraction connector seat, and the inner end which is located in the middle of the bottom of the cavity and has an insulating sealing pad. The cavity contains an inner wire that is connected to the inner wire adapter plate.

[0009] The heating suction cup assembly, from top to bottom, includes a heating suction cup, a heating suction cup pad, a heating plate, and a heating plate support. The heating suction cup has a number of suction channels B extending from the center outwards. The top surface has a number of suction holes communicating with the suction channels B. The bottom surface has a suction connector A communicating with the suction channels B. The suction connector A passes through the heating suction cup pad, the heating plate, and the heating plate support and abuts against an insulating sealing gasket. The insulating sealing gasket has sealing rings on its upper and lower surfaces. A common electrode conductive post is located on the side of the top surface of the heating suction cup. This common electrode conductive post corresponds to the common electrode probe of the probe fixing plate. The gate / element probe is mated to the wafer surface, forming an aging test circuit.

[0010] The heating suction cup is made of tungsten-copper alloy, which has good thermal conductivity. The heating suction cup gasket is a ceramic sheet, which has good thermal conductivity and insulation properties. The heating element is a mica heating element, which provides uniform heating per unit area. The central perforation facilitates uniform heating throughout the entire structure. The heating element support plate has heat insulation and reinforcement functions. The layered structure of the heating suction cup assembly can effectively reduce heat loss.

[0011] The heating chuck is secured to the cavity of the chuck base by a number of fixing bolts on its outer periphery. The bottom surface of the board adapter plate abuts against the top surface of the chuck base and is fixed by bolt assemblies. Before the aging test, the clamp probe board assembly is removed, and the wafer to be tested is placed on the heating chuck. Air is drawn out through the suction device, creating a negative pressure in suction channels A, B, and the suction port, firmly adhering the wafer to the heating chuck. During the aging test, the board adapter plate and the chuck base form a sealed cavity. Inert gas is supplied to the cavity through the gas inlet connector, protecting the wafer and providing thermal insulation to stabilize its temperature. The inner wiring adapter plate and inner wiring are used to transmit the current and signals required for the heating element of the heating chuck assembly.

[0012] Preferably, a certain number of board tray support columns are provided on the bottom of the outer periphery of the board tray, and the lower end of the board tray support columns extends beyond the lower end face of the chuck base, so that when the fixture probe board assembly or wafer aging test fixture is placed on other objects, only the bottom surface of the board tray support columns contacts the surface of the object, and the other structures are suspended.

[0013] Preferably, the bottom circular hole of the board tray is provided with clamping hooks on both sides for use with the clamping structure of the wafer loading and unloading equipment.

[0014] Preferably, the plate holder has wing plates on both sides, and the wing plates have strip-shaped holes A. The structure of the wing plates on both sides is designed to cooperate with the robotic arm of the loading and unloading equipment as well as for manual handling.

[0015] Preferably, the wing plate is provided with positioning grooves at the front and rear to cooperate with the limiting and positioning structure of the wafer loading and unloading equipment.

[0016] Preferably, a plate fixing plate is fixed in the middle of the top surface of the plate adapter plate. The bolt assembly includes a positioning bolt sleeve and a positioning bolt inside. The positioning bolt sleeve is fixed to the outer periphery of the top surface of the plate fixing plate. A bolt bearing is provided on the top of the positioning bolt. A compression spring A is provided between the positioning bolt and the positioning bolt sleeve. The lower end of the compression spring A abuts against the plate fixing plate, and the upper end abuts against the bolt bearing (outer ring). A bolt inner sleeve is provided in the hole of the plate adapter plate and the plate fixing plate through which the positioning bolt passes. The top surface of the outer periphery of the chuck base is provided with corresponding screw holes / nuts. The connection and separation of the clamp probe plate assembly and the clamp chuck assembly can be realized by tightening the bolt. When connecting and fixing, tighten the positioning bolt downwards. Under the positioning and guiding action of the positioning bolt sleeve, bolt bearing, bolt inner sleeve and other structures, the positioning bolt can be accurately screwed into the screw hole / nut. At this time, the compression spring A is in a compressed state. When separation is required, loosen the positioning bolt. The positioning bolt disengages from the screw hole / nut and will return to the top of the positioning bolt sleeve under the action of the compression spring A, maintaining a vertical state and not shaking.

[0017] Preferably, the top surface of the board tray is provided with an avoidance groove A corresponding to the transfer area of ​​the board adapter plate, and the bottom surface of the board fixing plate is provided with an avoidance groove B corresponding to the probe fixing plate, so as to avoid interference.

[0018] Preferably, the transition area is distributed in a ring shape on the outer periphery of the board transition plate.

[0019] Preferably, the bottom surface of the probe fixing plate is embedded with several board vision recognition components, and the top surface of the outer periphery of the chuck base is embedded with several loading and unloading vision recognition components. These vision recognition components, in conjunction with the automatic loading and unloading equipment, enable precise positioning of the wafer when placed in the center of the top surface of the heating chuck assembly, and precise positioning between the board adapter plate and the chuck base during the installation of the fixture probe board assembly and the fixture chuck assembly.

[0020] Preferably, the bottom surface of the chuck base is provided with a clamping limit groove for circumferential limiting to prevent the chuck base, i.e., the clamp, from rotating.

[0021] Preferably, the chuck base has an O-ring on its outer periphery top surface. After installation, the O-ring abuts against the card adapter plate to achieve a sealing effect.

[0022] Preferably, a chuck heat insulation sheet is provided at the bottom of the cavity, and an annular heat insulation sheet can also be provided on the side wall of the cavity to play the role of heat insulation and temperature stabilization.

[0023] Preferably, the heating suction cup has an insulating block embedded around its outer periphery corresponding to the fixing bolt. The fixing bolt passes through the insulating block, and a heating suction cup support column is fitted at its lower end. The insulating block and the support column are poor conductors of heat, and the support column suspends the heating suction cup assembly, thus providing a heat insulation effect.

[0024] Preferably, the heating suction cup has a certain number of sensor channels on its outer periphery, extending towards the center. Thermocouple sensors are installed within these channels, equidistantly distributed (e.g., three sensors), for collecting the temperature of the heating suction cup. The thermocouple sensors are installed by drilling and potting inside the heating suction cup to improve the accuracy of temperature acquisition. The signal is transmitted outward through an internal wire and an internal wire adapter plate.

[0025] Preferably, there are two inflation connectors, arranged such that the suction connector seat is located in the middle of the inner line adapter plate, and the inflation connectors are located on both sides of the inner line adapter plate. During operation, one inflation connector supplies inert gas into the cavity, and the gas in the cavity is discharged from the other inflation connector. After the cavity is filled with inert gas, one channel is closed, and the other channel is used for pressure maintenance.

[0026] Preferably, the heating suction cup has an opening on its outer periphery that communicates with the air extraction channel B, and a plug is provided in the opening for processing the air extraction channel B. After processing, the plug is installed for sealing.

[0027] The advantages of this utility model are: 1. The modular design of the device structure facilitates operation by testers, improves test efficiency, and enables large-scale testing; 2. It improves the reliability of the device and ensures the protection of wafer devices during aging tests; 3. The device is small in size, thus occupying little space. Attached Figure Description

[0028] Figure 1 The three-dimensional representation of this utility model Figure 1 ;

[0029] Figure 2 The three-dimensional representation of this utility model Figure 2 ;

[0030] Figure 3 This is a rear view of the present invention;

[0031] Figure 4 for Figure 3 Sectional view along the middle AA direction;

[0032] Figure 5This is a perspective view of the clamp probe board assembly in this utility model;

[0033] Figure 6 This is an exploded view of the clamp probe board assembly in this utility model;

[0034] Figure 7 This is a top view of the clamp probe board assembly in this utility model;

[0035] Figure 8 for Figure 7 Sectional view along the BB direction;

[0036] Figure 9 This is a perspective view of the clamp chuck assembly in this utility model;

[0037] Figure 10 This is a top view of the clamp chuck assembly in this utility model;

[0038] Figure 11 for Figure 10 A cross-sectional view along the CC direction;

[0039] Figure 12 The three-dimensional heating suction cup assembly in this utility model Figure 1 ;

[0040] Figure 13 The three-dimensional heating suction cup assembly in this utility model Figure 2 ;

[0041] Figure 14 This is an exploded view of the heating suction cup assembly in this utility model;

[0042] Figure 15 This is a top view of the heating suction cup assembly in this utility model;

[0043] Figure 16 for Figure 15 Sectional view along the DD direction;

[0044] Figure 17 for Figure 16 A sectional view along the EE direction;

[0045] Figure 18 This is a side view of the heating suction cup in this utility model;

[0046] Figure 19 for Figure 18 Sectional view along the FF direction.

[0047] Explanation of key component symbols in the diagram:

[0048] 100. Fixtures;

[0049] 110. Fixture probe board assembly; 111. Board support plate; 111.1. Board support plate support column; 111.2. Clamping hook; 111.3. Wing plate; 111.4. Strip hole A; 111.5. Positioning groove; 111.6. Clearance groove A; 112. Board adapter plate; 112.1. Adapter area; 113. Probe fixing plate; 113.1. Gate / electrode probe area; 113.2. Common probe; 113.3. Board vision recognition assembly; 114. Bolt assembly; 114.1. Positioning bolt sleeve; 114.2. Positioning bolt; 114.3. Bolt bearing; 114.4. Compression spring A; 115. Board fixing plate; 115.1. Clearance groove B;

[0050] 120. Clamp chuck assembly; 121. Chuck base; 121.1. Cavity; 121.2. Air extraction channel A; 121.3. Loading / unloading vision recognition assembly; 121.4. Clamp limiting groove; 122. Inflation connector; 123. Air extraction connector seat; 124. Inner wire adapter plate; 125. Insulating sealing gasket; 126. Inner wire; 127. O-ring; 128. Chuck heat insulation sheet;

[0051] 130. Heated suction cup assembly; 131. Heated suction cup; 131.1. Air extraction channel B; 131.2. Air extraction hole; 131.3. Common electrode conductive post; 131.4. Sensor channel; 131.5. Plug; 132. Heated suction cup gasket; 133. Heating element; 134. Heating element support plate; 135. Air extraction connector A; 136. Fixing bolt; 137. Heated suction cup insulating block; 138. Heated suction cup support column; 139. Thermocouple sensor. Detailed Implementation

[0052] To more clearly illustrate this utility model, the following description, in conjunction with the accompanying drawings, will provide further details.

[0053] Example 1: As Figure 1-4 As shown, a fixture for wafer aging test is provided. The fixture 100 includes a fixture probe board assembly 110, a fixture chuck assembly 120, and a heated suction cup assembly 130.

[0054] Combination Figure 5-8As shown, the clamp probe board assembly 110 includes a board support plate 111, a board adapter plate 112 fixed to the top surface of the board support plate 111, a probe fixing plate 113 fixed to the bottom surface of the board adapter plate 112, and a certain number of bolt assemblies 114. The board support plate 111 has a circular hole in the middle. The probe fixing plate 113 is located in the circular hole and has a gate / element probe area 113.1 on it. The gate / element probe area 113.1 has gate / element probes arranged in an array. Common probes 113.2 are provided on the side of the gate / element probe area 113.1. The top surface of the board adapter plate 112 has an adapter area 112.1, and the adapter area 112.1 has adapter contact points arranged in an array.

[0055] Combination Figure 9-11 As shown, the clamp chuck assembly 120 includes a chuck base 121. The top surface of the chuck base 121 has a cavity 121.1, and the side has an inflation connector 122, an air extraction connector seat 123, and an inner wire adapter plate 124. The inflation connector 122 communicates with the cavity 121.1. The chuck base 121 has an air extraction channel A121.2. The outer end of the air extraction channel A121.2 communicates with the air extraction connector seat 123, and the inner end is located in the middle of the bottom of the cavity 121.1 and is provided with an insulating sealing gasket 125. The cavity 121.1 contains an inner wire 126 that is connected to the inner wire adapter plate 124.

[0056] Combination Figure 12-19 As shown, the heating suction cup assembly 130 includes, from top to bottom, a heating suction cup 131, a heating suction cup pad 132, a heating plate 133, and a heating plate support plate 134. The heating suction cup 131 has a certain number of suction channels B131.1 extending from the center to the surrounding area. The top surface has a certain number of suction holes 131.2 communicating with the suction channels B131.1. The bottom surface has a suction connector A135 communicating with the suction channels B131.1. The suction connector A135 passes through the heating suction cup pad 132, the heating plate 133, and the heating plate support plate 134 and abuts against the insulating sealing gasket 125. The side of the top surface of the heating suction cup 131 has a common electrode conductive post 131.3.

[0057] The heating suction cup 131 is provided with a certain number of fixing bolts 136 on its outer periphery and is fixed in the cavity 121.1 of the chuck base 121 by the fixing bolts 136. The bottom surface of the plate adapter plate 112 abuts against the top surface of the outer periphery of the chuck base 121 and is fixed by bolt assembly 114.

[0058] Example 2: Combination Figure 5 and Figure 7-8 As shown, based on Embodiment 1, a certain number of plate support columns 111.1 are provided on the bottom of the outer periphery of the plate support plate 111, and clamping hooks 111.2 are provided on both sides of the bottom round hole.

[0059] The plate card holder 111 has wing plates 111.3 on both sides, and the wing plates 111.3 have strip holes A111.4 and positioning grooves 111.5 at the front and rear.

[0060] Example 3: Combination Figure 1 , Figure 4 , Figure 6-8 As shown, based on Embodiment 1 or Embodiment 2, a board fixing plate 115 is fixed in the middle of the top surface of the board adapter plate 112, and the bolt assembly 114 includes a positioning bolt sleeve 114.1 and a positioning bolt 114.2 inside it. The positioning bolt sleeve 114.1 is fixed to the outer periphery of the top surface of the board fixing plate 115, and a bolt bearing 114.3 is provided on the top of the positioning bolt 114.2. A compression spring A114.4 is provided between the positioning bolt 114.2 and the positioning bolt sleeve 114.1.

[0061] The top surface of the board tray 111 is provided with a clearance groove A111.6 corresponding to the transfer area 112.1 of the board adapter plate 112, and the bottom surface of the board fixing plate 115 is provided with a clearance groove B115.1 corresponding to the probe fixing plate 113.

[0062] The transition area 112.1 is distributed in a ring around the outer periphery of the board transition plate 112.

[0063] Example 4: Combination Figure 5 , Figure 9-10 As shown, based on Embodiment 1, Embodiment 2 or Embodiment 3, the bottom surface of the probe fixing plate 113 is embedded with a plurality of board visual recognition components 113.3, and the top surface of the outer periphery of the chuck base 121 is embedded with a plurality of loading and unloading visual recognition components 121.3.

[0064] Example 5: Combination Figure 2 , Figure 11 As shown, based on Embodiment 1, Embodiment 2, Embodiment 3 or Embodiment 4, the bottom surface of the chuck base 121 is provided with a clamp limiting groove 121.4.

[0065] Example 6: Combination Figure 9-11 As shown, based on the above embodiment, the chuck base 121 has an O-ring 127 on its outer top surface and a chuck heat insulation sheet 128 at the bottom of the cavity 121.1.

[0066] Example 7: Combination Figure 9-13 , Figure 15 , Figure 17-19 As shown, based on the above embodiment, the heating suction cup 131 has a heating suction cup insulating block 137 embedded on its outer periphery, corresponding to the fixing bolt 136. The fixing bolt 136 passes through the heating suction cup insulating block 137, and a heating suction cup support column 138 is sleeved at its lower end.

[0067] Example 8: Combination Figure 13 , 18 As shown in -19, based on the above embodiment, the heating suction cup 131 is provided with a certain number of sensor channels 131.4 on its outer periphery, and thermocouple sensors 139 are provided in the sensor channels 131.4.

[0068] Combination Figure 16-17 As shown, the heating suction cup 131 has an opening on its outer periphery that communicates with the air extraction channel B131.1, and a plug 131.5 is provided inside the opening.

[0069] Example 9: Combination Figure 9-10 As shown, based on the above embodiment, the number of the inflation connectors 122 is two, the air extraction connector seat 123 is located in the middle of the inner line adapter plate 124, and the inflation connectors 122 are located on both sides of the inner line adapter plate.

[0070] The above description is only a specific embodiment of the present utility model, but the structural features of the present utility model are not limited thereto. The present utility model can be used in similar products. Any changes or modifications made by those skilled in the art within the scope of the present utility model are covered by the patent scope of the present utility model.

Claims

1. A fixture for wafer burn-in testing, characterized by: The clamp (100) comprises a clamp probe board card assembly (110), a clamp chuck assembly (120) and a heating chuck assembly (130); The clamp probe board card assembly (110) comprises a board card supporting plate (111), a board card adapter plate (112) fixed on the top surface of the board card supporting plate (111), a probe fixing plate (113) fixed on the bottom surface of the board card adapter plate (112) and a plurality of bolt assemblies (114); the middle of the board card supporting plate (111) is provided with a circular hole, the probe fixing plate (113) is located in the circular hole and is provided with a gate / element probe area (113.1) on the top surface thereof; the gate / element probe area (113.1) is provided with gate / element probes arranged in an array; the side edge of the gate / element probe area (113.1) is provided with a common electrode probe (113.2); the top surface of the board card adapter plate (112) is provided with an adapter area (112.1) provided with adapter contacts arranged in an array; The two sides of the board card supporting plate (111) are provided with wing plates (111.3), the wing plates (111.3) are provided with strip-shaped holes A (111.4), and the front and back of the wing plates (111.3) are provided with positioning grooves (111.5); The clamp chuck assembly (120) comprises a chuck base (121), the top surface of the chuck base (121) is provided with a cavity (121.1), the side surface of the chuck base (121) is provided with an air charging connector (122), an air exhaust connector seat (123) and an inner wire adapter plate (124), the air charging connector (122) is communicated with the cavity (121.1), the chuck base (121) is provided with an air exhaust channel A (121.2), the outer end of the air exhaust channel A (121.2) is communicated with the air exhaust connector seat (123), the inner end of the air exhaust channel A (121.2) is located in the middle of the bottom of the cavity (121.1) and is provided with an insulating sealing block (125), the cavity (121.1) is provided with an inner wire (126) connected with the inner wire adapter plate (124), and the bottom surface of the chuck base (121) is provided with a clamp limiting groove (121.4); The heating chuck assembly (130) is used for fixing and heating a wafer.

2. The clamp for wafer burn-in test of claim 1, wherein: The heating chuck assembly (130) comprises, from top to bottom, a heating chuck (131), a heating chuck gasket (132), a heating sheet (133) and a heating sheet supporting plate (134), the heating chuck (131) is provided with a plurality of air exhaust channels B (131.1) extending from the middle to the periphery, the top surface of the heating chuck (131) is provided with a plurality of air exhaust holes (131.2) communicated with the air exhaust channels B (131.1), the middle of the bottom surface of the heating chuck (131) is provided with an air exhaust connector A (135) communicated with the air exhaust channels B (131.1), the air exhaust connector A (135) penetrates through the heating chuck gasket (132), the heating sheet (133) and the heating sheet supporting plate (134) and abuts against the insulating sealing block (125), and the side edge of the top surface of the heating chuck (131) is provided with a common electrode conductive column (131.3). The heating chuck (131) is provided with a plurality of fixing bolts (136) on the outer periphery and is fixed in the cavity (121.1) of the chuck base (121) through the fixing bolts (136). The bottom surface of the board card adapter plate (112) abuts against the outer periphery top surface of the chuck base (121) and is fixed through the bolt assembly (114).

3. The clamp for wafer burn-in test of claim 1, wherein: The outer periphery bottom of the board card adapter plate (111) is provided with a plurality of board card adapter plate support columns (111.1), and both sides of the bottom hole are provided with compression hooks (111.2).

4. The clamp for wafer burn-in test of claim 1, wherein: The top surface of the board card adapter plate (112) is fixed with a board card fixing plate (115) in the middle. The bolt assembly (114) comprises a positioning bolt sleeve (114.1) and a positioning bolt (114.2) in the positioning bolt sleeve (114.1). The positioning bolt sleeve (114.1) is fixed to the top surface of the board card fixing plate (115) on the outer periphery. The top of the positioning bolt (114.2) is provided with a bolt bearing (114.3). The compression spring A (114.4) is arranged between the positioning bolt (114.2) and the positioning bolt sleeve (114.1).

5. The clamp for wafer burn-in test of claim 4, wherein: The top surface of the board card adapter plate (111) is provided with an avoidance groove A (111.6) corresponding to the adapter area (112.1) of the board card adapter plate (112). The bottom surface of the board card fixing plate (115) is provided with an avoidance groove B (115.1) corresponding to the probe fixing plate (113). The adapter area (112.1) is annularly distributed on the outer periphery of the board card adapter plate (112).

6. The wafer burn-in fixture of claim 1, wherein: The bottom surface of the probe fixing plate (113) is embedded with a plurality of board card visual identification assemblies (113.3). The outer periphery top surface of the chuck base (121) is embedded with a plurality of feeding and discharging visual identification assemblies (121.3).

7. The clamp for wafer burn-in test of claim 1, wherein: The number of the inflation joints (122) is two.

8. The clamp for wafer burn-in test of claim 1, wherein: The outer periphery top surface of the chuck base (121) is provided with an O-ring (127), and the bottom of the cavity (121.1) is provided with a chuck heat insulation sheet (128).

9. The clamp for wafer burn-in test of claim 2, wherein: The outer periphery of the heating chuck (131) is embedded with a heating chuck insulating block (137) corresponding to the fixing bolt (136). The fixing bolt (136) penetrates through the heating chuck insulating block (137) and is sleeved with a heating chuck support column (138) at the lower end.

10. The clamp for wafer burn-in test of claim 2, wherein: The outer periphery of the heating chuck (131) is provided with a plurality of sensor channels (131.4). The sensor channels (131.4) are provided with thermocouple sensors (139). The outer periphery of the heating chuck (131) is provided with an opening communicating with the air suction channel B (131.1). The opening is provided with a plug (131.5).

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