A die bonding process

Abstract

The present invention relates to the technical field of light-emitting diode production, and specifically relates to a die bonding process, which includes the following steps: S1, cleaning and preheating a bracket; S2, performing a first injection of glue in the functional area of the bracket to form a first injection colloid and solidifying the first injection colloid; S3, starting a motor, driving a fixed wheel and a polishing fine rod to rotate by a synchronous belt, and polishing the top of the first injection colloid with the rotating polishing fine rod; S4, guiding two ends of a gold wire to be respectively connected to the first injection colloid and the functional area of the bracket; S5, performing a second injection of glue in the functional area and covering the first injection colloid with it to form a second injection colloid; S6, placing a chip on the second injection colloid and baking it to solidify the second injection colloid. In this application, by pre-drawing a gold wire connecting the die bonding glue and the functional area of the bracket, when the single-electrode chip and the die bonding glue are separated from the bracket, the single-electrode chip can still be electrically connected to the functional area of the bracket through the die bonding glue and the gold wire, thereby effectively reducing the rejection rate.

Description

Technical Field

[0001] The present invention relates to the technical field of light-emitting diode production, and specifically relates to a die bonding process. Background Art

[0002] The basic structure of an LED lamp is a solid-state semiconductor device. In a traditional LED, a semiconductor chip is mounted on a bracket with a positive electrode and a negative electrode, and is encapsulated with epoxy resin. The semiconductor chip is mounted in a designated area on the bracket to form a thermal path or an electrical path. The existing die bonding technology is to place the chip after injecting glue on the bracket to complete the die bonding operation. However, in this operation mode, when the surface of the bracket (substrate) is contaminated or the die bonding glue is affected by external factors and the bonding is not firm, the die bonding glue may peel off from the bracket (substrate) during the next process, resulting in the failure of the LED device.

[0003] Chinese Patent CN201721250433.8 relates to a new type of LED indicator light. It includes a first conductive bracket, a second conductive bracket, a connecting wire, and an LED chip. The LED chip is fixedly bonded to the upper end of the first conductive bracket by solder paste. The connecting wire connects the LED chip and the upper end of the second conductive bracket. The upper ends of the first conductive bracket and the second conductive bracket are encapsulated together by being wrapped with a high refractive index silicone resin.

[0004] For this kind of indicator light, the chip and the bracket are prone to separation before encapsulation, resulting in the failure of the equipment. Summary of the Invention

[0005] Based on this, in view of the problems in the prior art, it is necessary to provide a die bonding process.

[0006] To solve the problems in the prior art, the technical solution adopted by the present invention is as follows:

[0007] A die bonding process uses a micro-rod grinding machine. The micro-rod grinding machine includes a grinding box. In the grinding box, rotatable grinding thin rods are arranged at equal intervals. The grinding thin rods extend in the vertical direction. At the top end of each grinding thin rod, a fixed wheel coaxial with it is provided. In the grinding box, a synchronous belt driven by a motor is also provided. The outer circumferential surface of the fixed wheel is in frictional cooperation with the conveying surface of the synchronous belt. The die bonding process includes the following steps: S1, cleaning and preheating the bracket; S2, performing a first injection of glue in the functional area of the bracket to form a first injection colloid and solidifying the first injection colloid; S3, starting the motor, the synchronous belt drives the fixed wheel and the grinding thin rods to rotate, and the rotating grinding thin rods grind the top end of the first injection colloid; S4, guiding the two ends of a gold wire to be respectively connected to the first injection colloid and the functional area of the bracket; S5, performing a second injection of glue in the functional area and covering the first injection colloid to form a second injection colloid; S6, placing the chip on the second injection colloid and then baking to solidify the second injection colloid.

[0008] Preferably, in S4, an ultrasonic gold wire welding technique is adopted to weld a gold wire for connecting the first injection colloid and the functional area of the bracket.

[0009] Preferably, the length of the gold wire is 1 - 1.5 times the long side of the chip.

[0010] Preferably, the second injection colloid covers 1 / 2 - 2 / 3 of the length of the gold wire.

[0011] Preferably, at least 1 / 3 of the length of the gold wire is exposed from the second injection colloid.

[0012] Preferably, the grinding machine further includes a bearing and a fixing ring. The fixing wheel is rotatably arranged in the grinding box. The bearings are equally spaced at the bottom of the grinding box. The output shaft of the bearing extends in the vertical direction. The fixing ring is coaxially and fixedly arranged on the inner ring of the bearing. A first spline section that is coaxially and slidably engaged with the bearing is arranged on the grinding rod. First limiting rings are arranged at both the upper and lower ends of the first spline section. A cylindrical cavity coaxial with it is arranged on the inner circumference of the fixing wheel. A second spline section that penetrates the fixing wheel and is fitted and slid with it is arranged at the top of the grinding rod. A second limiting ring is arranged on the second spline section and is located inside. A spring is also sleeved on the grinding rod. The two ends of the spring respectively abut against the top of the second limiting ring and the top of the cylindrical cavity.

[0013] Preferably, the grinding machine further includes a scissor - type telescopic frame and a regulator. The scissor - type telescopic frame and the regulator are arranged in the grinding box. The scissor - type telescopic frame includes a fixed point at the middle position of the bottom of the grinding box and hinge points distributed on both sides of the fixed point. The grinding rod vertically passes through the fixed point and the hinge points and is rotatably engaged with them. The fixing wheel is rotatably arranged on the fixed point and the hinge points. The regulator includes an actuator hinged to both sides of the clamping - type telescopic frame. When the two actuators move towards each other, the adjacent hinge points approach the fixed point at equal intervals.

[0014] Preferably, the scissor - type telescopic frame includes a first connecting rod, a second connecting rod, a third connecting rod, and a fourth connecting rod. The middle positions of the first connecting rod and the second connecting rod are rotatably connected to form a scissor structure. The grinding rod is arranged at the rotating part. One end of the third connecting rod and the fourth connecting rod is hinged to the actuator of the regulator. The other ends of the third connecting rod and the fourth connecting rod are respectively rotatably connected to the same side of the first connecting rod and the second connecting rod.

[0015] Preferably, the regulator includes a first sliding plate, a second sliding plate, and a bidirectional lead screw. The first sliding plate and the bidirectional lead screw are slidably arranged in the grinding box along the telescopic direction of the scissor - type telescopic frame. The bidirectional lead screw is rotatably arranged in the grinding box. Inner - thread fixing ears that mesh with the two sections of threads on the bidirectional lead screw are arranged on both the first sliding plate and the bidirectional lead screw. The connection part of the third connecting rod and the fourth connecting rod is rotatably connected to the opposite side of the second sliding plate and the bidirectional lead screw.

[0016] The present application also relates to a micro-rod grinding machine, which includes a grinding box. Rotatable grinding thin rods are arranged at equal intervals in the grinding box. The grinding thin rods extend in the vertical direction. A fixed wheel coaxial with the grinding thin rod is arranged at the top end of the grinding thin rod. A synchronous belt driven by a motor is also arranged in the grinding box. The outer circumferential surface of the fixed wheel is in frictional engagement with the conveying surface of the synchronous belt.

[0017] The beneficial effects of the present application compared with the prior art are as follows:

[0018] 1. By pre-dragging a gold wire connecting the die bonding glue and the functional area of the bracket, when the single-electrode chip is separated from the bracket, the single-electrode chip can still be electrically connected to the functional area of the bracket through the die bonding glue and the gold wire, thus effectively reducing the rejection rate.

[0019] 2. The present application uses ultrasonic gold wire welding technology to weld a gold wire to connect the first injection colloid and the functional area of the bracket.

[0020] 3. The grinding thin rod is arranged in the fixed circle in the vertical direction through the first spline section, so that the grinding thin rod can rotate relative to the bearing and slide in the vertical direction. When the bottom end of the grinding thin rod abuts against the top end of the first injection colloid, the second limiting ring rises in the cylindrical cavity against the elastic force of the spring, avoiding the direct rigid abutment of the bottom end of the grinding thin rod against the first injection colloid, thereby preventing it from damaging the functional area of the bracket.

[0021] 4. Through the scissor-type telescopic frame and the regulator, the distance between adjacent grinding thin rods can be synchronously adjusted. Start the regulator to make its two execution parts move towards or away from each other, so that the hinge points on both sides of the scissor-type telescopic frame approach the fixed point at equal intervals, thereby being able to adjust the distance between the grinding thin rods installed on it.

[0022] 5. By rotatably connecting the middle positions of the first connecting rod and the second connecting rod to form a scissor structure, when the connection points of the third connecting rod and the fourth connecting rod on both sides move towards or away from each other, the connection points of adjacent first connecting rods and second connecting rods move at equal intervals to adjust the distance between the grinding thin rods installed on them.

[0023] 6. By rotating the bidirectional lead screw to make it rotate stably in the grinding box, since the first sliding plate and the second sliding plate are slidably arranged in the grinding box along the telescopic direction of the scissor-type telescopic frame, and internal threads meshing with the bidirectional lead screw are arranged on both the first sliding plate and the second sliding plate, the first sliding plate and the second sliding plate can move towards or away from each other inside, thereby adjusting the telescopic amount of the scissor-type telescopic frame by adjusting the position of the connection between the third connecting rod and the fourth connecting rod.

[0024] 7. In the present application, the injection area on the tiny bracket can be ground by the micro-rod grinding machine. Description of the Drawings

[0025] Figure 1 This is a schematic diagram of the stent die bonding process of the present application.

[0026] Figure 2 This is a perspective view of the thin rod grinding machine of the present application.

[0027] Figure 3 This is an internal perspective view of the thin rod grinding machine of the present application.

[0028] Figure 4 This is a perspective view of the thin rod grinding machine after removing the top cover of the present application.

[0029] Figure 5 This is a perspective view of the scissor-type telescopic frame and the regulator of the present application.

[0030] Figure 6 This is an axial sectional view of the grinding thin rod and the fixed wheel of the present application.

[0031] The reference numerals in the figure are:

[0032] 1a - stent; 1b - first electrode; 1c - second electrode; 1d - first injection colloid; 1e - second injection colloid; 1f - gold wire; 1g - single electrode chip; 2 - grinding box; 3 - grinding thin rod; 3a - first spline segment; 3a1 - first limiting ring; 3b - second spline segment; 3b1 - second limiting ring; 3c - spring; 4 - fixed wheel; 4a - cylindrical cavity; 5 - synchronous belt; 6 - bearing; 7 - fixing ring; 8a - first connecting rod; 8b - second connecting rod; 8c - third connecting rod; 8d - fourth connecting rod; 9a - first sliding plate; 9b - second sliding plate; 9c - bidirectional lead screw. Detailed implementation manners

[0033] To further understand the features, technical means, and the specific purposes and functions achieved by the present invention, the present invention will be described in further detail below with reference to the drawings and specific implementation manners.

[0034] As Figures 1-6 shown, the present application provides:

[0035] A die bonding process uses a micro-rod grinding machine. The micro-rod grinding machine includes a grinding box 2, in which rotatable grinding fine rods 3 are arranged at equal intervals. The grinding fine rods 3 extend in the vertical direction. At the top of the grinding fine rod 3, a fixed wheel 4 coaxial with it is provided. In the grinding box 2, a synchronous belt 5 driven by a motor is also provided. The outer circumferential surface of the fixed wheel 4 is in frictional engagement with the conveying surface of the synchronous belt 5. The die bonding process includes the following steps: S1, cleaning and preheating the bracket; S2, performing the first glue injection in the functional area of the bracket to form a first glue injection body and solidifying the first glue injection body; S3, starting the motor, the synchronous belt 5 drives the fixed wheel 4 and the grinding fine rods 3 to rotate, and the rotating grinding fine rods 3 grind the top of the first glue injection body; S4, guiding the two ends of a gold wire to be respectively connected to the first glue injection body and the functional area of the bracket; S5, performing the second glue injection in the functional area and covering the first glue injection body to form a second glue injection body; S6, placing the chip on the second glue injection body and then baking it to solidify the second glue injection body.

[0036] Based on the above embodiments, the technical problem that the present application wants to solve is that when the functional area of the bracket is contaminated or the die bonding glue and silver glue are not firmly bonded due to external factors, the single-electrode chip and the solidified die bonding glue are easily peeled off from the bracket, resulting in the failure of the LED device. For this reason, the present application pre-traces a gold wire connecting the die bonding glue and the functional area of the bracket, so that when the single-electrode chip and the die bonding glue are separated from the bracket, the single-electrode chip can still be electrically connected to the functional area of the bracket through the die bonding glue and the gold wire, thereby effectively reducing the rejection rate;

[0037] On the bracket 1a, a first electrode 1b and a second electrode 1c are provided, where the first electrode 1b and the second electrode 1c are not connected to each other. Select the first electrode 1b or the second electrode 1c as the functional area for bonding the single-electrode chip 1g. In the present application, the first electrode 1b is selected as the functional area, and the following functional areas all refer to the first electrode 1b;

[0038] The bottom end of the single-electrode chip 1g is the negative electrode, and the negative electrode is electrically connected to the first electrode 1b through the die bonding glue and silver glue. The top end of the single-electrode chip 1g is provided with a positive electrode, and another gold wire is led from the positive electrode to form a path with the second electrode 1c before encapsulation;

[0039] First, clean and preheat the bracket to prevent the dirt on the bracket from affecting its bonding effect. Preheating is also convenient for the first glue injection body 1d to solidify on the bracket 1a;

[0040] The die bonding glue is dot-injected on the bracket 1a through a dispenser to form a first glue injection body, and then the bracket is baked for the first time to make the first glue injection body 1d completely solidify. Since the top of the first glue injection body 1d will have protrusions or depressions due to dot-injection at this time, its top needs to be ground smoothly to facilitate welding the gold wire 1f;

[0041] That is, start the grinding machine so that the bottom end of the grinding rod 3 abuts against the top end of the first glue injection body 1d. At the same time, start the motor to drive the synchronous belt 5 to rotate. The outer circumferential surface of the fixed wheel 4 is in frictional fit with the conveying surface of the synchronous belt 5, so that the grinding rod 3 rotates at a high speed on the grinding box 2, and the rotating grinding rod 3 grinds the top end of the first glue injection body 1d until the top end of the first glue injection body 1d is smooth;

[0042] Guide both ends of a gold wire 1f to be welded to the first glue injection body 1d and the first electrode 1b respectively, and then send it to the LED automatic die bonder;

[0043] Through the LED automatic die bonder, second glue injection is carried out on the first electrode 1b to cover the first glue injection body 1d to form the second glue injection body 1e. At the same time, the single-electrode chip 1g is placed on the top end of the second glue injection body 1e in a viscous state;

[0044] After the bonding is completed, bake the bracket for the second time so that the second glue injection body 1e solidifies to complete the die bonding operation;

[0045] When the first glue injection body 1d and the second glue injection body 1e are separated from the first electrode 1b due to the dirt on the surface of the first electrode 1b or external force factors, the single-electrode chip 1g is always in a conductive state with the first electrode 1b through the first glue injection body 1d, the second glue injection body 1e and the gold wire 1f, thereby effectively reducing the rejection rate.

[0046] Furthermore:

[0047] In S4, an ultrasonic gold wire welding technology is used to weld a gold wire to connect the functional areas of the first glue injection body and the bracket.

[0048] Based on the above embodiments, the technical problem that this application wants to solve is how to guide a gold wire to connect the first electrode 1b and the first glue injection body 1d. For this reason, this application uses ultrasonic gold wire welding technology to weld a gold wire to connect the functional areas of the first glue injection body 1d and the bracket 1a. The ultrasonic gold wire welding technology is used to realize the surface welding of different media and is a physical change process. First, the head end of the gold wire must be processed to form a sphere, and the metal surface to be welded is preheated first; then, under the combined action of time and pressure, the gold wire ball produces plastic deformation on the metal welding surface, so that the two media achieve reliable contact, and through ultrasonic friction vibration, metal bonds are formed between the two metal atoms under the action of atomic affinity, realizing the welding of the gold wire lead, and making the acoustic gold wire welding technology an effective connection of the first electrode 1b and the first glue injection body 1d through the gold wire.

[0049] Furthermore:

[0050] The length of the gold wire is 1-1.5 times the long side of the chip.

[0051] Based on the above embodiments, the technical problem that this application aims to solve is how to enable the gold wire to stably connect the bracket and the chip. To this end, in this application, the length of the gold wire is made 1-1.5 times the long side of the chip, so that the gold wire can stably connect the functional area of the bracket and the second injection colloid.

[0052] Furthermore:

[0053] The second injection colloid covers 1 / 2 - 2 / 3 of the length of the gold wire.

[0054] Based on the above embodiments, the technical problem that this application aims to solve is how to ensure that the second injection colloid and the gold wire can be stably connected without separation. To this end, in this application, by making the second injection colloid cover 1 / 2 - 2 / 3 of the length of the gold wire, even when subjected to external forces, the gold wire is not easily separated from the second injection colloid.

[0055] Furthermore:

[0056] At least 1 / 3 of the length of the gold wire is exposed from the second injection colloid.

[0057] Based on the above embodiments, the technical problem that this application aims to solve is how the gold wire stably connects the functional area of the bracket and the second injection colloid. To this end, in this application, by making at least 1 / 3 of the length of the gold wire exposed from the second injection colloid, the exposed section of the gold wire can stably connect the functional area and the second injection colloid.

[0058] As Figure 6 shown, furthermore:

[0059] The grinding machine further includes a bearing 6 and a fixing ring 7. The fixed wheel 4 is rotatably arranged in the grinding box 2. The bearings 6 are equidistantly arranged at the bottom end of the grinding box 2. The output shaft of the bearing 6 extends in the vertical direction. The fixing ring 7 is coaxially and fixedly arranged on the inner ring of the bearing 6. The grinding fine rod 3 is provided with a first spline section 3a that is coaxially and slidably matched with the bearing 6, and first limiting rings 3a1 are arranged at both the upper and lower ends of the first spline section 3a. A cylindrical cavity 4a coaxial with it is arranged on the inner circumference of the fixed wheel 4. The top end of the grinding fine rod 3 is further provided with a second spline section 3b that penetrates the fixed wheel 4 and is fitted and slid with it. A second limiting ring 3b1 located in 4b0 is arranged on the second spline section 3b. A spring 3c is also sleeved on the grinding fine rod 3. The two ends of the spring 3c respectively abut against the top end of the second limiting ring 3b1 and the top end of the cylindrical cavity 4a.

[0060] Based on the above embodiments, the technical problem that the present application aims to solve is that if the bottom end of the polishing thin rod 3 rigidly abuts against the top end of the first injection colloid, it may damage the functional area of the bracket. For this reason, the present application arranges the polishing thin rod 3 in the fixed ring 7 along the vertical direction through the first spline section 3a, and the fixed ring 7 is fixedly arranged in the bearing 6, so that the polishing thin rod 3 can rotate relative to the bearing 6 and slide along the vertical direction. When the fixed wheel 4 rotates due to the friction force of the synchronous belt 5, the polishing thin rod 3 rotates synchronously with the fixed wheel 4 through the second spline section 3b, and the second limiting ring 3b1 slides along the vertical direction in the cylindrical cavity 4a. When the bottom end of the polishing thin rod 3 and the top end of the first injection colloid abut against each other, the second limiting ring 3b1 rises in the cylindrical cavity 4a against the elastic force of the spring 3c, avoiding the bottom end of the polishing thin rod 3 directly and rigidly abutting against the first injection colloid, thereby preventing it from damaging the functional area of the bracket.

[0061] As Figure 6 shown, further:

[0062] The grinding machine further includes a scissor-type telescopic frame and a regulator. The scissor-type telescopic frame and the regulator are arranged in the grinding box 2. The scissor-type telescopic frame includes a fixed point at the middle position of the bottom of the grinding box 2 and hinge points distributed on both sides of the fixed point. The polishing thin rod 3 vertically passes through the fixed point and the hinge points and is rotationally matched with them. The fixed wheel 4 is rotatably arranged at the fixed point and the hinge points. The regulator includes an execution part hinged to both sides of the clamping-type telescopic frame. When the two execution parts move towards each other, the adjacent hinge points approach the fixed point at equal intervals.

[0063] Based on the above embodiments, the technical problem that the present application aims to solve is how to adjust the distance between adjacent polishing thin rods 3 according to the distance of brackets with different spacings. For this reason, the present application can synchronously adjust the distance between adjacent polishing thin rods 3 through the scissor-type telescopic frame and the regulator. Start the regulator to make its two execution parts move towards or away from each other, so that the hinge points on both sides of the scissor-type telescopic frame approach the fixed point at equal intervals, thereby being able to adjust the distance between the polishing thin rods 3 installed thereon.

[0064] As Figure 6 shown, further:

[0065] The scissor-type telescopic frame includes a first connecting rod 8a, a second connecting rod 8b, a third connecting rod 8c, and a fourth connecting rod 8d. The middle positions of the first connecting rod 8a and the second connecting rod 8b are rotatably connected to form a scissor structure. The polishing thin rod 3 is arranged at the rotating part. One end of the third connecting rod 8c and the fourth connecting rod 8d is hinged to the execution part of the regulator, and the other ends of the third connecting rod 8c and the fourth connecting rod 8d are respectively rotatably connected to the same side of the first connecting rod 8a and the second connecting rod 8b.

[0066] Based on the above embodiments, the technical problem that this application aims to solve is how to adjust the distance between the fixed points of the scissor-type telescopic frame. To this end, this application forms a scissor structure by rotatably connecting the middle positions of the first link 8a and the second link 8b. When the connection points of the third link 8c and the fourth link 8d on both sides move towards or away from each other, the connection points of the adjacent first link 8a and the second link 8b move equidistantly to adjust the distance between the polishing thin rods 3 installed thereon.

[0067] As Figure 6 shown, further:

[0068] The regulator includes a first sliding plate 9a, a second sliding plate 9b, and a bidirectional lead screw 9c. The first sliding plate 9a and the bidirectional lead screw 9c are slidably arranged in the polishing box 2 along the telescopic direction of the scissor-type telescopic frame. The bidirectional lead screw 9c is rotatably arranged in the polishing box 2, and both the first sliding plate 9a and the bidirectional lead screw 9c are provided with internal thread fixing ears meshing with the two sections of threads on the bidirectional lead screw 9c. The connection between the third link 8c and the fourth link 8d is rotatably connected on the opposite side of the second sliding plate 9b and the bidirectional lead screw 9c.

[0069] Based on the above embodiments, the technical problem that this application aims to solve is how to adjust the distance between the two sides of the scissor-type telescopic frame. To this end, this application rotates the bidirectional lead screw 9c to make it rotate stably in the polishing box 2. Since the first sliding plate 9a and the second sliding plate 9b are slidably arranged in the polishing box 2 along the telescopic direction of the scissor-type telescopic frame, and both the first sliding plate 9a and the second sliding plate 9b are provided with internal thread fixing ears meshing with the bidirectional lead screw 9c, the first sliding plate 9a and the second sliding plate 9b can move towards or away from each other in 01, so as to adjust the telescopic amount of the scissor-type telescopic frame by adjusting the position of the connection between the third link 8c and the fourth link 8d.

[0070] As Figures 2 to 6 shown, further:

[0071] A micro-rod polishing machine includes a polishing box 2. Rotatable polishing thin rods 3 are arranged equidistantly in the polishing box 2. The polishing thin rods 3 extend in the vertical direction. A fixed wheel 4 coaxial with the top of the polishing thin rods 3 is provided at the top of the polishing thin rods 3. A synchronous belt 5 driven by a motor is also arranged in the polishing box 2. The outer circumferential surface of the fixed wheel 4 is in frictional cooperation with the conveying surface of the synchronous belt 5.

[0072] Based on the above embodiments, the technical problem that this application aims to solve is how to polish the glue injection area on the micro bracket. To this end, this application makes the polishing thin rods 3 gradually approach the glue injection area and abut against it by making the relative position closer to the bracket. When the motor is started, the synchronous belt 5 rotates in the polishing box 2, and then can drive the fixed wheel 4 to rotate in the polishing box 2, so that the polishing thin rods 3 rotate at a high speed at the bottom of the polishing box 2 to polish the top of the glue injection area.

[0073] In this application, a gold wire connecting the die bonding glue and the functional area of the bracket is pre-tensioned, so that when the single-electrode chip is separated from the bracket by the die bonding glue, the single-electrode chip can still be electrically connected to the functional area of the bracket through the die bonding glue and the gold wire, thereby effectively reducing the rejection rate.

[0074] The above embodiments only represent one or several implementation manners of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims

1. A die bonding process, characterized in that, It uses a micro-rod grinding machine, which includes a grinding box (2). Rotatable grinding fine rods (3) are arranged at equal intervals in the grinding box (2). The grinding fine rods (3) extend in the vertical direction. A fixed wheel (4) coaxial with it is arranged at the top end of the grinding fine rod (3). A synchronous belt (5) driven by a motor is also arranged in the grinding box (2). The outer circumferential surface of the fixed wheel (4) is in frictional cooperation with the conveying surface of the synchronous belt (5). The die bonding process includes the following steps: S1, cleaning and preheating the bracket; S2, performing the first injection molding in the functional area of the bracket to form a first injection molding body and solidifying the first injection molding body; S3, starting the motor, the synchronous belt (5) drives the fixed wheel (4) and the grinding fine rods (3) to rotate, and the rotating grinding fine rods (3) grind the top end of the first injection molding body; S4, guiding the two ends of a gold wire to be respectively connected to the first injection molding body and the functional area of the bracket; S5, performing the second injection molding in the functional area and covering the first injection molding body to form a second injection molding body; S6, placing the chip on the second injection molding body and then baking it to solidify the second injection molding body; The grinding machine further includes bearings (6) and fixing rings (7). The fixed wheel (4) is rotatably arranged in the grinding box (2). The bearings (6) are arranged at equal intervals at the bottom end of the grinding box (2). The output shaft of the bearing (6) extends in the vertical direction. The fixing ring (7) is coaxially and fixedly arranged on the inner ring of the bearing (6). The grinding fine rod (3) is provided with a first spline section (3a) that is coaxially and slidably engaged with the bearing (6), and first limiting rings (3a1) are arranged at both the upper and lower ends of the first spline section (3a). A cylindrical cavity (4a) coaxial with it is arranged on the inner circumference of the fixed wheel (4). A second spline section (3b) that penetrates and is fitted and slid with the fixed wheel (4) is also arranged at the top end of the grinding fine rod (3). A second limiting ring (3b1) located in the 4b0 is arranged on the second spline section (3b). A spring (3c) is also sleeved on the grinding fine rod (3). The two ends of the spring (3c) respectively abut against the top end of the second limiting ring (3b1) and the top end of the cylindrical cavity (4a); The grinding machine further includes a scissor-type telescopic frame and a regulator. The scissor-type telescopic frame and the regulator are arranged in the grinding box (2). The scissor-type telescopic frame includes a fixed point at the middle position of the bottom of the grinding box (2) and hinge points distributed on both sides of the fixed point. The grinding fine rods (3) vertically pass through the fixed point and the hinge points and are rotatably engaged with them. The fixed wheel (4) is rotatably arranged on the fixed point and the hinge points. The regulator includes an execution part hinged to both sides of the clamping-type telescopic frame. When the two execution parts move towards each other, the adjacent hinge points approach the fixed point at equal intervals; The scissor-type telescopic frame includes a first connecting rod (8a), a second connecting rod (8b), a third connecting rod (8c) and a fourth connecting rod (8d). The middle positions of the first connecting rod (8a) and the second connecting rod (8b) are rotatably connected to form a scissor structure. The polishing thin rod (3) is arranged at the rotating part. One ends of the third connecting rod (8c) and the fourth connecting rod (8d) are hinged to the execution part of the regulator, and the other ends of the third connecting rod (8c) and the fourth connecting rod (8d) are respectively rotatably connected to the same side of the first connecting rod (8a) and the second connecting rod (8b). The regulator includes a first sliding plate (9a), a second sliding plate (9b) and a bidirectional lead screw (9c). The first sliding plate (9a) and the bidirectional lead screw (9c) are slidably arranged in the polishing box (2) along the telescopic direction of the scissor-type telescopic frame. The bidirectional lead screw (9c) is rotatably arranged in the polishing box (2), and internal thread fixing ears engaged with two sections of threads on the bidirectional lead screw (9c) are arranged on both the first sliding plate (9a) and the bidirectional lead screw (9c). The connection part of the third connecting rod (8c) and the fourth connecting rod (8d) is rotatably connected to the opposite side of the second sliding plate (9b) and the bidirectional lead screw (9c).

2. The die bonding process according to claim 1, wherein In S4, an ultrasonic gold wire welding technology is used to weld a gold wire to connect the first injection colloid and the functional area of the bracket.

3. A die bonding process according to claim 1 or 2, characterized in that, The length of the gold wire is 1-1.5 times the long side of the chip.

4. A die bonding process according to claim 1 or 2, characterized in that, The second injection colloid covers 1 / 2 - 2 / 3 of the length of the gold wire.

5. A die bonding process according to claim 4, wherein At least 1 / 3 of the length of the gold wire is exposed from the second injection colloid.

6. A micro-rod grinding machine, which is applied to a die bonding process as described in claim 1, and is characterized in that, It includes a polishing box (2). Rotatable polishing thin rods (3) are equidistantly arranged in the polishing box (2). The polishing thin rods (3) extend in the vertical direction. A fixed wheel (4) coaxial with the polishing thin rod (3) is arranged at the top end of the polishing thin rod (3). A synchronous belt (5) driven by a motor is also arranged in the polishing box (2). The outer circumferential surface of the fixed wheel (4) is in frictional cooperation with the conveying surface of the synchronous belt (5).

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