Metal needle mass transfer pyrolysis film packaging process

Abstract

The invention discloses a metal needle mass transfer pyrolysis film packaging process, which belongs to the technical field of electronic packaging, and comprises the following steps: providing a carrier plate; pasting a pyrolysis film on the carrier plate; providing a carrier; arranging metal needles on the carrier plate through the carrier; the carrier is removed, so that the metal needle is pasted on the pyrolysis film; inversely arranging the carrier plate, the pyrolysis film and the metal needle on the bottom plate; fixing the metal needles on the bottom plate through reflow soldering, and removing the carrier plate and the pyrolysis film; mounting a chip on the bottom plate; packaging the metal needles and the outer part of the mounting chip through a packaging material; and grinding the packaging material to expose the metal needle and the mounting chip. Through the process of pasting the pyrolytic film on the carrier plate, the copper column can be pressed during reflow soldering, an auxiliary soldering effect is achieved, the metal needle is not prone to deviation, poor soldering cannot be caused, the metal needle can be directly removed after reflow soldering, grinding removal is not needed, and the process difficulty is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of electronic packaging, and in particular relates to a metal needle mass transfer pyrolysis film packaging process. Background Art

[0002] Metal needle packaging is an electronic device packaging technology that can be used for the packaging of high-power electronic components such as power modules. This packaging method uses metal needles or copper sheets (CuClip) as interconnect components to connect the chip to the external circuit to improve the electrical and thermal performance of the package. In the prior art, metal needle packaging mainly adopts a modular design, and the metal needles are soldered to the copper foil with solder paste. However, this method has some limitations. For example, the copper foil is difficult to reuse after use and usually needs to be removed by grinding. This process is not only inefficient, but also reduces the service life of the tool. Summary of the invention

[0003] In view of the above situation, in order to overcome the defects of the prior art, the present invention adopts the process of sticking a pyrolytic film on the carrier board, which can press the copper pillar during reflow soldering, play a role in auxiliary welding, and prevent the metal needle from being easily displaced and causing poor welding.

[0004] In order to achieve the above object, the following technical scheme is adopted: The present invention provides a metal needle mass transfer pyrolysis film packaging process, comprising:

[0005] Provide carrier board;

[0006] Pasting a pyrolytic film on the carrier;

[0007] Provide vehicles;

[0008] Arrange and place metal needles on the carrier plate by using the carrier;

[0009] removing the carrier, so that the metal needle is adhered to the pyrolysis film;

[0010] placing the carrier plate, the pyrolysis film and the metal needle upside down on the bottom plate;

[0011] Fixing the metal pins on the base plate by reflow soldering and removing the carrier plate and the pyrolysis film;

[0012] Installing a chip on the base plate;

[0013] Encapsulating the metal pins and the mounting chip with an encapsulation material;

[0014] The packaging material is ground to expose the metal pins and the mounted chip.

[0015] Furthermore, the metal needle comprises a copper needle.

[0016] Furthermore, the carrier comprises a steel mesh.

[0017] Furthermore, the arrangement of the openings of the steel mesh is determined according to the arrangement of the copper needles on the product.

[0018] Furthermore, the copper needles are arranged and placed on the carrier plate by the carrier, including placing the copper needles on the steel mesh by vibration, magnetic attraction or brush.

[0019] Furthermore, mounting the chip on the base plate includes: flipping the chip on the base plate.

[0020] Furthermore, the bottom plate includes: a substrate, a carrier board, and a PCB board.

[0021] The beneficial effects of the present invention are:

[0022] The present invention uses a process of attaching a pyrolytic film on a carrier board, which can press down the copper column during reflow soldering, play a role in auxiliary soldering, prevent the metal needle from being easily offset and will not cause poor soldering, and can be directly removed after reflow soldering without grinding and removal. The present invention does not need to consider the problems of alignment and copper foil grinding, and reduces the difficulty of the process. The carrier board can be used as an auxiliary fixture for reflow soldering, which can well control the problem of metal needle cold soldering, and the pyrolytic film has a relatively high viscosity, which improves the stability of metal needle absorption and placement. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of pasting the pyrolysis film on the carrier;

[0024] Figure 2 A schematic diagram of the structure in which the carrier is placed on the pyrolysis film;

[0025] Figure 3 Schematic diagram of the structure where the metal needle is attached to the pyrolysis film in order to remove the carrier;

[0026] Figure 4 It is a schematic diagram of the structure in which the carrier plate, the pyrolysis film and the metal needle are inverted on the bottom plate;

[0027] Figure 5 Schematic diagram of the structure after removing the carrier plate and pyrolysis film;

[0028] Figure 6 A schematic diagram of the structure after the chip is installed and packaged with packaging materials;

[0029] Figure 7 Schematic diagram of the structure showing metal needles and chips after grinding.

[0030] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0031] Legend: 1. Carrier; 2. Pyrolytic film; 3. Metal needle; 4. Carrier; 5. Base plate; 6. Chip; 7. Packaging material. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] Unless otherwise defined, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein may be applied to the present invention. The preferred implementation methods and materials described herein are for demonstration purposes only and are not intended to limit the content of this application.

[0034] The experimental methods in the following examples are conventional methods unless otherwise specified, and the experimental materials used in the following examples are purchased from commercial channels unless otherwise specified.

[0035] Example

[0036] A metal needle mass transfer pyrolysis film packaging process

[0037] The packaging process comprises:

[0038] Provide carrier board;

[0039] It is necessary to select suitable substrate materials, such as BT resin and FR-4, which have good electrical and mechanical properties. The substrate needs to be precisely processed to ensure that its flatness and dimensional accuracy meet the requirements of subsequent processes.

[0040] like Figure 1 As shown, a pyrolytic film is pasted on the carrier;

[0041] Pyrolytic film is a special polymer film. The film is treated at high temperature to change its molecular structure, thereby destroying the viscosity of the glue and making it lose its adhesive effect.

[0042] Provide carrier board;

[0043] The carrier plate is made of high temperature resistant material, such as ceramic or special alloy, and is used to stick the pyrolytic film on it;

[0044] like Figure 2 As shown, the metal needles are arranged and placed on the carrier plate by the carrier;

[0045] The metal needle may be a copper needle, and the carrier may be a steel mesh having openings, and the arrangement of the openings of the steel mesh is determined according to the arrangement of the copper needle on the product;

[0046] The carrier is used to arrange and place copper pins on the carrier. As connecting devices, the copper pins need to be accurately placed in the openings of the carrier. This step is usually completed using vibration, magnetic attraction or other precise automated equipment to place the copper pins accurately in the openings.

[0047] like Figure 3 As shown, the carrier is removed, for example, the steel mesh is removed, so that the metal needle is adhered to the pyrolysis film;

[0048] like Figure 4 As shown, the carrier, pyrolytic film and metal needles are inverted on the base plate, and the metal needles are fixed on the base plate by reflow soldering; the pyrolytic film loses its viscosity due to high temperature during reflow soldering, making it easy to separate it from the metal needles.

[0049] like Figure 5 As shown, the carrier plate and the pyrolysis film are removed;

[0050] The pyrolytic film can hold down the copper pillar during reflow soldering, playing a role in assisting soldering, making it difficult for the metal needle to deviate and causing poor soldering. It can be removed directly after reflow soldering without the need for grinding.

[0051] Mounting a chip on the base plate includes: flipping the chip on the base plate;

[0052] like Figure 6 As shown, the metal needles and the mounting chip are packaged outside by packaging materials;

[0053] Encapsulation materials, such as epoxy resin, not only provide protection but also provide good electrical insulation and mechanical support;

[0054] like Figure 7 As shown, the packaging material is ground to expose the metal needles and the mounting chip;

[0055] This step uses high-precision grinding equipment to ensure that the exposed metal needles and chip surfaces are flat, which is convenient for subsequent testing and use;

[0056] The bottom plate includes: a substrate, a carrier plate, and a PCB board.

[0057] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0058] The present invention and its implementation methods are described above, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual application is not limited thereto. In short, if ordinary technicians in the field are inspired by it and design methods and embodiments similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the protection scope of the present invention.

Claims

1. A metal needle mass transfer pyrolysis film packaging process, Features: include: Provide carrier board; Pasting a pyrolytic film on the carrier; Provide vehicles; Arrange and place metal needles on the carrier plate by using the carrier; removing the carrier, so that the metal needle is adhered to the pyrolysis film; placing the carrier plate, the pyrolysis film and the metal needle upside down on the bottom plate; Fixing the metal pins on the base plate by reflow soldering and removing the carrier plate and the pyrolysis film; Installing a chip on the base plate; Encapsulating the metal pins and the mounting chip with an encapsulation material; The packaging material is ground to expose the metal pins and the mounted chip.

2. A metal needle mass transfer pyrolysis film packaging process according to claim 1, Features: The metal needle comprises a copper needle.

3. The metal needle mass transfer pyrolysis film packaging process according to claim 1, Features: The carrier includes a steel mesh.

4. The metal needle mass transfer pyrolysis film packaging process according to claim 3, Features: The arrangement of the openings of the steel mesh is determined according to the arrangement of the copper needles on the product.

5. The metal needle mass transfer pyrolysis film packaging process according to claim 1, Features: The copper needles are arranged and placed on the carrier plate by the carrier, including placing the copper needles on the steel mesh by vibration, magnetic attraction or brush.

6. The metal needle mass transfer pyrolysis film packaging process according to claim 1, Features: Mounting the chip on the base plate includes: flipping the chip on the base plate.

7. The metal needle mass transfer pyrolysis film packaging process according to claim 1, Features: The bottom plate includes: a substrate, a carrier plate, and a PCB board.

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