Crimping method and device for eutectic sintering of chip and electronic equipment

Abstract

The invention provides a crimping method and device for eutectic sintering of a chip and electronic equipment. The crimping method comprises the following steps: receiving a first instruction and a second instruction sent by a user; according to the first instruction, picking up a magnetic-affinity metal sheet, and placing the magnetic-affinity metal sheet on a chip of the pre-assembled substrate to obtain an assembled substrate; wherein the pre-assembled substrate sequentially comprises a preset substrate, a pre-formed soldering lug and a chip from bottom to top; according to the second instruction, the assembled substrate is placed in a preset magnetic tool, so that the magnetic affinity metal sheet is adsorbed through the magnetic force of a magnet in the magnetic tool, and the chip is crimped; according to the mode, the magnetic-philic metal sheet is placed on the surface of the chip, the magnetic force of the magnet in the magnetic tool is used for attracting the magnetic-philic metal sheet, so that pressure is applied to the chip during sintering, the processing difficulty of the magnetic-philic metal sheet is small, the magnetic-philic metal sheet can be automatically picked up, manual intervention is not needed, the operation is more convenient, and the surface of the chip can be effectively prevented from being scratched.

Description

Technical Field

[0001] The present invention relates to the technical field of sintering manufacturing, and in particular, to a crimping method, device and electronic device for chip eutectic sintering. Background Art

[0002] In the related art, in order to improve the quality of chip eutectic sintering and reduce the porosity, when performing chip eutectic sintering, a gravity pressing block is usually added to the chip surface or the pressure is locally increased (such as, needle contact type or hollowed-out pressing block, etc.). In this method, the size of the pressing block needs to correspond to the size of the chip, and the processing difficulty is relatively large; moreover, during the operation process, due to the heavy pressing block, the machine tool cannot be used for picking and placing, and manual intervention is required for picking and placing, which is likely to cause scratches on the chip surface. Summary of the Invention

[0003] The purpose of the present invention is to provide a crimping method, device and electronic device for chip eutectic sintering, so as to reduce the processing difficulty of the pressing block and avoid scratches on the chip surface.

[0004] A crimping method for chip eutectic sintering provided by the present invention includes: receiving a first instruction and a second instruction issued by a user; picking up a ferromagnetic metal sheet according to the first instruction and placing the ferromagnetic metal sheet on a chip of a pre-assembled substrate to obtain an assembled substrate; wherein, the pre-assembled substrate includes, from bottom to top in sequence: a preset substrate, a preformed solder sheet and a chip; according to the second instruction, placing the assembled substrate in a preset magnetic tooling to adsorb the ferromagnetic metal sheet by the magnetic force of a magnet in the magnetic tooling, so as to crimp the chip.

[0005] Further, the thickness of the ferromagnetic metal sheet is less than 2 millimeters.

[0006] Further, the size of the ferromagnetic metal sheet is 80%-100% of the size of the chip.

[0007] Further, the magnet in the magnetic tooling is located directly below the chip.

[0008] Further, the temperature resistance of the magnet is greater than 350°.

[0009] Further, the upper surface of the magnet is in direct contact with the lower surface of the assembled substrate; or, there is a preset distance between the upper surface of the magnet and the lower surface of the assembled substrate.

[0010] Further, the material of the ferromagnetic metal sheet includes at least one of the following: iron, cobalt, nickel.

[0011] Further, the magnetic force does not exceed the maximum tolerable pressure of the chip.

[0012] A crimping device for chip eutectic sintering provided by the present invention, the device includes: a receiving module for receiving a first instruction and a second instruction issued by a user; a picking module for picking up a paramagnetic metal sheet according to the first instruction and placing the paramagnetic metal sheet on a chip of a pre-assembled substrate to obtain an assembled substrate; wherein, the pre-assembled substrate includes, from bottom to top in sequence: a preset substrate, a preformed solder sheet, and a chip; a crimping module for placing the assembled substrate in a preset magnetic tooling according to the second instruction to adsorb the paramagnetic metal sheet by the magnetic force of a magnet in the magnetic tooling to crimp the chip.

[0013] An electronic device provided by the present invention includes a processor and a memory, the memory stores machine-executable instructions that can be executed by the processor, and the processor executes the machine-executable instructions to implement the crimping method for chip eutectic sintering in any one of the above.

[0014] The crimping method, device and electronic device for chip eutectic sintering provided by the present invention receive a first instruction and a second instruction issued by a user; pick up a paramagnetic metal sheet according to the first instruction and place the paramagnetic metal sheet on a chip of a pre-assembled substrate to obtain an assembled substrate; wherein, the pre-assembled substrate includes, from bottom to top in sequence: a preset substrate, a preformed solder sheet, and a chip; according to the second instruction, place the assembled substrate in a preset magnetic tooling to adsorb the paramagnetic metal sheet by the magnetic force of a magnet in the magnetic tooling to crimp the chip; in this way, a paramagnetic metal sheet is placed on the chip surface, and the paramagnetic metal sheet is attracted by the magnetic force of the magnet in the magnetic tooling, so as to apply pressure to the chip during sintering. The paramagnetic metal sheet is easy to process, can be automatically picked up, does not require manual intervention, is more convenient to operate, and can effectively avoid scratching the chip surface. Description of the Drawings

[0015] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required to be used in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 It is a flowchart of a crimping method for chip eutectic sintering provided by an embodiment of the present invention;

[0017] Figure 2 It is a schematic diagram of an assembled substrate provided by an embodiment of the present invention;

[0018] Figure 3 It is a schematic diagram of an assembled substrate placed in a preset magnetic tooling provided by an embodiment of the present invention;

[0019] Figure 4 Schematic diagram of an assembled substrate placed in a preset magnetic tooling provided by an embodiment of the present invention;

[0020] Figure 5 Schematic diagram of the structure of an electronic device provided by an embodiment of the present invention.

[0021] Icons: 20 - preset substrate; 21 - preformed solder pad; 22 - chip; 23 - magnetophilic metal sheet; 24 - magnet; 25 - fixing jig. Specific embodiments

[0022] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0023] In the related art, there are problems such as difficult processing of the gravity block and easy scratching of the chip surface when adding a gravity block on the chip surface or locally increasing the pressure. In addition, the method of adding a gravity block on the chip surface also has high requirements for the surface finish of the block, which further increases the processing difficulty of the block. Based on this, the embodiments of the present invention provide a method, device, and electronic device for crimping in chip eutectic sintering. This technology can be applied to applications that require crimping of chips in chip eutectic sintering.

[0024] For ease of understanding of this embodiment, first, a method for crimping in chip eutectic sintering disclosed in the embodiments of the present invention will be introduced, as Figure 1 shown, the method includes the following steps:

[0025] Step S101, receiving a first instruction and a second instruction issued by the user.

[0026] The above first instruction can be used to indicate picking up a magnetophilic metal sheet from the position where the magnetophilic metal sheet is stored; the above second instruction can be used to indicate placing the assembled substrate in a preset magnetic tooling; in actual implementation, the user can trigger the corresponding instruction control through the operation interface to issue the above first instruction and second instruction.

[0027] Step S102, picking up the magnetophilic metal sheet according to the first instruction and placing the magnetophilic metal sheet on the chip of the pre-assembled substrate to obtain an assembled substrate; wherein, the pre-assembled substrate includes, from bottom to top, a preset substrate, a preformed solder pad, and a chip.

[0028] In this embodiment, the materials that need to be prepared in advance include: a preset substrate, a preformed solder sheet, a chip, a magnetophilic metal sheet, a magnet, and a fixing fixture (optional); among them, the preset substrate can be selected according to the packaging requirements. For example, it can be a DBC (Direct Bonding Copper) substrate, etc.; the size of the preformed solder sheet is related to the size of the above-mentioned chip to be sintered, usually similar to the size of the chip. The composition of the preformed solder sheet is related to the sintering process and can be a copper alloy solder sheet, a gold-tin alloy solder sheet, etc.; the above-mentioned chip can be selected according to actual needs. For example, it can be an IGBT chip, a MOS chip, a diode chip, etc.; the composition of the above-mentioned magnetophilic metal sheet should contain a metal that can be adsorbed by a magnet; the size of the above-mentioned magnet can usually be determined in advance according to experiments to ensure that an appropriate magnetic force can be provided; in actual implementation, the preformed solder sheet can be picked up to a specified position on the preset substrate in advance, and then the chip can be picked up and placed on the preformed solder sheet to obtain a pre-assembled substrate. Then, according to the first instruction, the magnetophilic metal sheet is picked up from the position where the magnetophilic metal sheet is stored and placed on the upper surface of the chip to obtain an assembled substrate. This automatic picking method of the magnetophilic metal sheet is not likely to scratch the surface of the chip.

[0029] As Figure 2 shown in the schematic diagram of an assembled substrate, it can be seen that the bottom layer is the preset substrate, and the preformed solder sheet, the chip, and the magnetophilic metal sheet are arranged in sequence upward.

[0030] Step S103: According to the second instruction, place the assembled substrate in a preset magnetic fixture to adsorb the magnetophilic metal sheet through the magnetic force of the magnet in the magnetic fixture to press the chip.

[0031] The above-mentioned magnetic fixture can only include a magnet; it can also be a fixing fixture that includes a magnet contained therein; in actual implementation, the assembled substrate can be placed in the magnetic fixture according to the second instruction. Since the magnetophilic metal sheet is magnetophilic, the magnet in the magnetic fixture can magnetically adsorb the magnetophilic metal sheet on the upper surface of the chip, thereby increasing the pressure on the surface of the chip.

[0032] The above-mentioned method for crimping a chip by eutectic sintering receives a first instruction and a second instruction issued by a user; picks up a magnetophilic metal sheet according to the first instruction and places the magnetophilic metal sheet on the chip of a pre-assembled substrate to obtain an assembled substrate; wherein the pre-assembled substrate includes, from bottom to top in sequence: a preset substrate, a preformed solder sheet, and a chip; according to the second instruction, places the assembled substrate in a preset magnetic tooling to adsorb the magnetophilic metal sheet by the magnetic force of a magnet in the magnetic tooling so as to crimp the chip; this method places a magnetophilic metal sheet on the chip surface and sucks the magnetophilic metal sheet by the magnetic force of the magnet in the magnetic tooling, thereby realizing applying pressure to the chip during sintering. The magnetophilic metal sheet is easy to process, can be automatically picked up, does not require manual intervention, is more convenient to operate, and can effectively avoid scratching the chip surface.

[0033] Further, the thickness of the magnetophilic metal sheet is less than 2 mm.

[0034] In actual implementation, to facilitate picking up the magnetophilic metal sheet and avoid scratching the chip at the same time, the thickness of the magnetophilic metal sheet is usually selected to be less than 2 mm. Specifically, an appropriate thickness value can be selected according to actual requirements. For example, 1 mm, 800 microns, 500 microns, etc.; preferably, when the thickness of the magnetophilic metal sheet is less than 500 microns, the pressure on the chip surface can be effectively reduced.

[0035] Further, the size of the magnetophilic metal sheet is 80%-100% of the size of the chip.

[0036] The above-mentioned size can specifically refer to the length and width dimensions, that is, the length of the magnetophilic metal sheet can be 80%-100% of the length of the chip, and the width of the magnetophilic metal sheet can be 80%-100% of the width of the chip; usually, a size similar to the size of the chip is selected as the size of the magnetophilic metal sheet. For example, if the size of the chip is 10 mm * 10 mm, the size of the magnetophilic metal sheet can be selected as 9 mm * 9 mm, 8 mm * 8 mm, etc.; if the size of the magnetophilic metal sheet is too large, it will cause material waste, and if it is too small, there may be a problem of insufficient crimping force.

[0037] Further, the magnet in the magnetic tooling is located directly below the chip;

[0038] In actual implementation, the magnet is usually set at a position directly below the chip to ensure that during the eutectic sintering process of the chip, the crimping force applied to the chip is sufficient and is a force perpendicular to the chip surface to ensure the crimping effect; if the magnet is on one side of the chip, the crimping force applied to the chip may not be perpendicular to the chip surface. In this way, during the eutectic sintering process of the chip, due to the melting of the preformed solder sheet, the chip may deviate from the preset welding position, reducing the welding quality.

[0039] Further, the temperature resistance of the magnet is greater than 350°. Since the magnetic tooling needs to be heated together with the assembled substrate in a sintering device and heated to the sintering temperature of the preformed solder sheet for sintering, the magnet is required to have high temperature resistance. Since the magnet may need to be applicable to different sintering conditions, considering the sintering requirements and the maximum sintering temperature of the sintering device, the temperature resistance of the magnet is selected to be higher than 350°

[0040] Further, the upper surface of the magnet is in direct contact with the lower surface of the assembled substrate; or, a preset distance is provided between the upper surface of the magnet and the lower surface of the assembled substrate.

[0041] In actual implementation, as Figure 3 shown in a schematic diagram of an assembled substrate placed in a preset magnetic tooling, the upper surface of the magnet in the magnetic tooling can be directly in contact with the lower surface of the assembled substrate. This method requires precise control of the magnetic force magnitude; as another optimized method, as Figure 4 shown in a schematic diagram of an assembled substrate placed in a preset magnetic tooling, the magnet can be arranged inside the magnetic tooling so that the upper surface of the magnet is not in direct contact with the lower surface of the assembled substrate. For example, the size of the magnet can be smaller than the size of the substrate, so that the magnet is located in the fixture groove and there is a certain air gap from the lower surface of the assembled substrate; or a fixture material is further provided between the magnet and the lower surface of the assembled substrate to separate the magnet and the substrate.

[0042] Further, the material of the magnetophilic metal sheet includes at least one of the following: iron, cobalt, nickel. Since the magnetophilic metal sheet needs to be adsorbed by the magnet, its material usually needs to contain at least one or more of iron, cobalt, and nickel. Of course, other metal materials can also be doped in addition to these materials. The surface finish of the magnetophilic metal sheet can be selected according to actual needs. Preferably, the surface finish can be selected from Ra0.2 to Ra0.4.

[0043] Further, the magnetic force does not exceed the maximum tolerable pressure of the chip.

[0044] In actual implementation, a suitable magnet can be preselected through experiments to generate a suitable magnetic force. The magnet cannot be placed on the chip surface. During the placement process, the magnet will suck the tube shell and automatically adsorb within a certain range from the tube shell, which is difficult to operate and easily damages the chip. Place the magnet in the tooling. After the magnetophilic metal sheet is placed, it can suck the magnetophilic metal sheet within a certain range to increase the pressure on the chip. The magnetic force is less than or equal to the magnitude of the force that the chip can withstand to avoid damaging the chip. For example, the magnetic force can be 2g, etc. The pressure on the chip surface is increased by the magnet adsorbing the magnetophilic metal sheet.

[0045] An embodiment of the present invention provides a crimping device for chip eutectic sintering. The device includes: a receiving module for receiving a first instruction and a second instruction issued by a user; a picking module for picking up a ferromagnetic metal sheet according to the first instruction and placing the ferromagnetic metal sheet on a chip of a pre-assembled substrate to obtain an assembled substrate; wherein the pre-assembled substrate includes, from bottom to top in sequence: a preset substrate, a preformed solder sheet, and a chip; a crimping module for placing the assembled substrate in a preset magnetic tooling according to the second instruction to adsorb the ferromagnetic metal sheet by the magnetic force of a magnet in the magnetic tooling so as to crimp the chip.

[0046] In the above crimping device for chip eutectic sintering, a ferromagnetic metal sheet is placed on the chip surface, and the ferromagnetic metal sheet is attracted by the magnetic force of the magnet in the magnetic tooling, so as to apply pressure to the chip during sintering. The ferromagnetic metal sheet is easy to process, can be automatically picked up, does not require manual intervention, is more convenient to operate, and can effectively avoid scratching the chip surface.

[0047] Further, the thickness of the ferromagnetic metal sheet is less than 2 mm.

[0048] Further, the size of the ferromagnetic metal sheet is 80%-100% of the size of the chip.

[0049] Further, the magnet in the magnetic tooling is located directly below the chip.

[0050] Further, the temperature resistance of the magnet is greater than 350°.

[0051] Further, the upper surface of the magnet is in direct contact with the lower surface of the assembled substrate; or, there is a preset distance between the upper surface of the magnet and the lower surface of the assembled substrate.

[0052] Further, the material of the ferromagnetic metal sheet includes at least one of the following: iron, cobalt, nickel.

[0053] Further, the magnetic force does not exceed the maximum tolerable pressure of the chip.

[0054] The implementation principle and the technical effects generated by the crimping device for chip eutectic sintering provided by the embodiment of the present invention are the same as those of the foregoing embodiment of the crimping method for chip eutectic sintering. For a brief description, for the parts not mentioned in the embodiment of the crimping device for chip eutectic sintering, reference may be made to the corresponding content in the foregoing embodiment of the crimping method for chip eutectic sintering.

[0055] An embodiment of the present invention also provides an electronic device. Refer to Figure 5 As shown, the electronic device includes a processor 130 and a memory 131. The memory 131 stores machine-executable instructions that can be executed by the processor 130, and the processor 130 executes the machine-executable instructions to implement the above-mentioned crimping method for chip eutectic sintering.

[0056] Further, Figure 5 the electronic device shown further includes a bus 132 and a communication interface 133, and the processor 130, the communication interface 133, and the memory 131 are connected through the bus 132.

[0057] Among them, the memory 131 may include a high-speed random access memory (RAM), and may also include a non-volatile memory, such as at least one disk memory. The communication connection between the system network element and at least one other network element is realized through at least one communication interface 133 (which may be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. can be used. The bus 132 may be an ISA bus, a PCI bus, an EISA bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 5 only a bidirectional arrow is used in the figure, but it does not mean that there is only one bus or one type of bus.

[0058] The processor 130 may be an integrated circuit chip with signal processing capabilities. In the implementation process, the steps of the above method can be completed by the integrated logic circuit in the hardware of the processor 130 or the instructions in the form of software. The above-mentioned processor 130 may be a general-purpose processor, including a central processing unit (CPU for short), a network processor (NP for short), etc.; it may also be a digital signal processor (DSP for short), an application specific integrated circuit (ASIC for short), a field-programmable gate array (FPGA for short), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present invention can be directly embodied as being executed by the hardware decoding processor, or executed by the combination of the hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory 131, and the processor 130 reads the information in the memory 131 and combines its hardware to complete the steps of the method in the foregoing embodiments.

[0059] An embodiment of the present invention further provides a machine-readable storage medium storing machine-executable instructions, which, when called and executed by a processor, cause the processor to implement the above-mentioned chip eutectic sintering crimping method. For specific implementation, reference may be made to the method embodiment and will not be elaborated herein.

[0060] A computer program product of the chip eutectic sintering crimping method, device and electronic device provided by an embodiment of the present invention includes a computer-readable storage medium storing program codes, and the instructions included in the program codes can be used to execute the method described in the foregoing method embodiment. For specific implementation, reference may be made to the method embodiment and will not be elaborated herein.

[0061] If the above functions are implemented in the form of software function units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of various embodiments of the present invention.

Claims

1. A crimping method for chip eutectic sintering, characterized in that, the method comprises: receiving a first instruction and a second instruction issued by a user; picking up a magnetophilic metal sheet according to the first instruction and placing the magnetophilic metal sheet on a chip of a pre-assembled substrate to obtain an assembled substrate; wherein, the pre-assembled substrate sequentially comprises, from bottom to top: a preset substrate, a preformed solder sheet, and the chip; placing the assembled substrate in a preset magnetic tooling according to the second instruction, so as to adsorb the magnetophilic metal sheet by the magnetic force of a magnet in the magnetic tooling to crimp the chip.

2. The method according to claim 1, characterized in that, the thickness of the magnetophilic metal sheet is less than 2 mm.

3. The method according to claim 1, characterized in that, the size of the magnetophilic metal sheet is 80%-100% of the size of the chip.

4. The method according to claim 1, characterized in that, the magnet in the magnetic tooling is located directly below the chip.

5. The method according to claim 1, characterized in that, the temperature resistance of the magnet is greater than 350°.

6. The method according to claim 1, characterized in that, the upper surface of the magnet is in direct contact with the lower surface of the assembled substrate; or, a preset distance is provided between the upper surface of the magnet and the lower surface of the assembled substrate.

7. The method according to claim 1, characterized in that, the material of the magnetophilic metal sheet comprises at least one of the following: iron, cobalt, nickel.

8. The method according to claim 1, characterized in that, the magnetic force does not exceed the maximum tolerable pressure of the chip.

9. A crimping device for chip eutectic sintering, characterized in that, the device comprises: a receiving module for receiving a first instruction and a second instruction issued by a user; a picking module for picking up a magnetophilic metal sheet according to the first instruction and placing the magnetophilic metal sheet on a chip of a pre-assembled substrate to obtain an assembled substrate; wherein, the pre-assembled substrate sequentially comprises, from bottom to top: a preset substrate, a preformed solder sheet, and the chip; a crimping module for placing the assembled substrate in a preset magnetic tooling according to the second instruction, so as to adsorb the magnetophilic metal sheet by the magnetic force of a magnet in the magnetic tooling to crimp the chip.

10. An electronic device, characterized in that, comprising a processor and a memory, the memory stores machine-executable instructions capable of being executed by the processor, and the processor executes the machine-executable instructions to implement the crimping method for chip eutectic sintering according to any one of claims 1-8.

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