Device and method for improving polishing efficiency of dielectric layer material in plastic packaging process

Abstract

The application discloses a device and method for improving the grinding efficiency of medium layer material in a plastic sealing process, and a specially designed buffer layer is added to the side of the plastic sealing equipment in contact with the medium layer material; when the plastic sealing is formed, the double effects of the copper bump and the buffer layer form a structure with the bump area protruding; when grinding, the protruding plastic sealing layer and a small part of the plane plastic sealing layer are mainly ground to expose the copper bump, so that the grinding area is reduced, the grinding time is shortened, and the consumption of the grinding wheel is reduced.

Description

Technical Field

[0001] This invention relates to the field of chip packaging technology, and in particular to an apparatus and method for improving the grinding efficiency of dielectric layer materials in molding processes. Background Technology

[0002] like Figure 1 As shown, the fan-out process includes the following steps: substrate preparation, chip placement, molding, grinding, and fan-out packaging. In the molding stage, dielectric material is needed to protect the chips after chip placement. In the grinding stage, the dielectric material is higher than the conductive copper bumps, and grinding equipment is needed to grind away the excess dielectric material and expose the conductive copper bumps.

[0003] like Figure 2 The diagram shown is a schematic of the grinding stage in the prior art. The thickness of the dielectric layer material is the same in all areas to be ground, which requires a large grinding area and results in a large consumption of grinding wheels. Correspondingly, in the molding step, the large molding area leads to a large consumption of dielectric layer material.

[0004] Therefore, it is necessary to develop a device and method to improve the grinding efficiency of the dielectric layer material in the molding process to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to design an apparatus and method for improving the grinding efficiency of dielectric layer materials in the molding process in order to solve the above-mentioned problems.

[0006] The present invention achieves the above objectives through the following technical solutions:

[0007] An apparatus for improving the grinding efficiency of dielectric layer materials in molding processes includes two molds, a buffer layer on the working surface of one mold, a chip placed on the other mold, and dielectric layer material placed between the buffer layer and the chip.

[0008] Specifically, the buffer layer includes a first buffer layer and a second buffer layer connected on one side. The second buffer layer is disposed close to the medium layer material, and the hardness of the first buffer layer is greater than that of the second buffer layer.

[0009] Preferably, both the first buffer layer and the second buffer layer are silicone or PET films.

[0010] Methods for improving the grinding efficiency of dielectric layer materials in molding processes include:

[0011] Before molding and pressing, a buffer layer is placed between the dielectric layer material and the adjacent mold.

[0012] During mold closing, the ends of the copper bumps press against the medium layer material and the buffer layer, forming grooves on the buffer layer;

[0013] After molding, a planar molding layer is formed on the chip surface and a raised molding layer is formed on the upper end of the copper bump;

[0014] During grinding, grind away all the raised plastic sealant and part of the flat plastic sealant to expose the copper bump end face.

[0015] Specifically, the formed planar molding layer and the raised molding layer are continuously arranged.

[0016] The beneficial effects of this invention are as follows:

[0017] In this application, a specially designed buffer layer is added to the side of the molding equipment that contacts the dielectric layer material. During molding, due to the dual effect of the copper bumps and the buffer layer, a structure with protruding bump areas is formed. During grinding, the copper bumps are exposed by grinding away the protruding molding layer and a small part of the planar molding layer, which ultimately reduces the grinding area, shortens the grinding time, and reduces the consumption of grinding wheels. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the existing fan-out process;

[0019] Figure 2 This is a schematic diagram of the grinding structure of dielectric layer materials in the prior art; where a is before grinding and b is after grinding;

[0020] Figure 3 This is a schematic diagram of the molding process in this application; where a is chip arrangement, b is molding / pressing, c is mold closing, and d is molding.

[0021] Figure 4 This is a schematic diagram of the grinding structure of the dielectric layer material in this application; where a is before grinding and b is after grinding.

[0022] Figure 5 This is a schematic diagram of the structure of the buffer layer in this application;

[0023] In the diagram: 1-First mold; 2-Chip; 21-Copper bump; 3-Dielectric layer material; 4-Buffer layer; 41-First buffer layer; 42-Second buffer layer; 5-Second mold. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] In the description of this invention, it should be understood that the terms "upper," "lower," "inner," "outer," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this invention and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0028] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0029] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0030] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0031] like Figure 3 As shown, the device for improving the grinding efficiency of dielectric layer material in the molding process includes two molds. A buffer layer 4 is provided on the working surface of the second mold 5. The chip 2 is placed on the first mold 1, and the dielectric layer material 3 is placed between the buffer layer 4 and the chip 2.

[0032] like Figure 5As shown, the buffer layer 4 includes a first buffer layer 41 and a second buffer layer 42 connected on one side. The second buffer layer 42 is disposed close to the dielectric layer material 3. The hardness of the first buffer layer 41 is greater than that of the second buffer layer 42. The second buffer layer 42 is made of silicone with a hardness of 50-55 degrees and a thickness of 1 mm; the first buffer layer 41 is made of silicone with a hardness of 75-80 degrees and a thickness of 1 mm.

[0033] Preferably, the first buffer layer 41 and the second buffer layer 42 are both silicone or PET films.

[0034] like Figure 3 and 4 As shown, a method for improving the grinding efficiency of dielectric layer material 3 in the molding process includes:

[0035] Before molding and pressing, a buffer layer 4 is placed between the medium layer material 3 and the adjacent mold.

[0036] During mold closing, the ends of the copper bump 21 press against the medium layer material 3 and the buffer layer 4, forming a groove on the buffer layer 4;

[0037] After molding, a planar molding layer is formed on the surface of chip 2 and a raised molding layer is formed on the upper end of copper bump 21. The planar molding layer and the raised molding layer are continuously arranged. A conical surface is formed at the continuous part.

[0038] During grinding, grind away all the raised plastic sealant and part of the flat plastic sealant to expose the end face of the copper bump 21.

[0039] In this embodiment, the height of the copper bump 21 protruding from the surface of the chip 2 is selected to be 50 μm. Correspondingly, the thickness of the planar molding layer is slightly less than the height of the copper bump 21, and the thickness of the raised molding layer is 20 μm.

[0040] In some embodiments, the orientation of the first mold 1, the second mold 5, the buffer layer 4, and the chip 2 can be reversed, meaning that the entire device can be turned upside down and its functions can still be realized.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An apparatus for improving the grinding efficiency of dielectric layer materials in a molding process, comprising two molds, characterized in that: A buffer layer is set on the working surface of one mold, the chip is placed on another mold, and the dielectric layer material is placed between the buffer layer and the chip. Copper bumps protrude from the chip surface. When the mold is closed, the ends of the copper bumps squeeze the dielectric layer material and the buffer layer, forming grooves on the buffer layer. After molding, a planar molding layer is formed on the chip surface and a raised molding layer is formed on the upper end of the copper bumps. The thickness of the planar molding layer is slightly less than the height of the copper bumps. During grinding, all the raised molding layer and part of the planar molding layer are removed, exposing the end face of the copper bumps.

2. The apparatus for improving the grinding efficiency of dielectric layer materials in the molding process according to claim 1, characterized in that: The buffer layer includes a first buffer layer and a second buffer layer connected on one side. The second buffer layer is disposed close to the medium layer material, and the hardness of the first buffer layer is greater than that of the second buffer layer.

3. The apparatus for improving the grinding efficiency of dielectric layer materials in the molding process according to claim 2, characterized in that, Both the first and second buffer layers are made of silicone or PET film.

4. A method for improving the grinding efficiency of dielectric layer materials in a molding process, characterized in that, include: Before molding and pressing, a buffer layer is placed between the dielectric layer material and the adjacent mold. During mold closing, the ends of the copper bumps press against the medium layer material and the buffer layer, forming grooves on the buffer layer; After molding, a planar molding layer is formed on the chip surface and a raised molding layer is formed on the upper end of the copper bump; the planar molding layer and the raised molding layer are continuously arranged after molding; During grinding, grind away all the raised plastic sealant and part of the flat plastic sealant to expose the copper bump end face.

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