CN108848616B

CN108848616B - Structure for forming circuit board adhesive film and adhesive film forming method

Info

Publication number: CN108848616B
Application number: CN201810866851.2A
Authority: CN
Inventors: 杨乐; 安金平; 高原
Original assignee: Xian Microelectronics Technology Institute
Current assignee: Xian Microelectronics Technology Institute
Priority date: 2018-08-01
Filing date: 2018-08-01
Publication date: 2020-11-24
Anticipated expiration: 2038-08-01
Also published as: CN108848616A

Abstract

The invention discloses a structure for forming a bonding adhesive film of a circuit board, which comprises two core plates and two isolation films, wherein the core plates are respectively arranged at the top and the bottom, the isolation films are arranged between two epoxy light plates, and an adhesive film is arranged between the isolation films; the two epoxy light plates are provided with clamps to clamp the two epoxy light plates up and down, and a cold plate printed circuit board adhesive film forming method is also disclosed; after the two core plates, the two isolating films and the adhesive film are stacked and fixed in sequence, positioning and milling are carried out to complete the processing of the adhesive film with the required model; the problems of edge burrs, poor size precision and soft adhesion in the appearance processing process of the cold plate printed circuit board bonding adhesive film are effectively solved, the processing precision and quality of the cold plate printed circuit board bonding adhesive film are improved, the bonding adhesive film can be suitable for a printed cold plate board with a more complex structure and higher requirement, and the processing capacity of the cold plate printed circuit board is improved.

Description

Structure for forming circuit board adhesive film and adhesive film forming method

Technical Field

The invention belongs to the field of cold plate printed circuits, and particularly relates to a structure for forming a circuit board adhesive film and an adhesive film forming method.

Background

With the trend toward light, thin, short, high-density mounting of electronic devices and the increase in the frequency of use of CPUs, printed circuit boards for electronic interconnection are developing toward high-density and high-precision, and thus high-power printed board assemblies are required to have excellent heat dissipation performance and dimensional stability. The cold plate printed board can effectively solve the problem of heat dissipation, so that the dimensional stability of the printed board is ensured, the problem of expansion with heat and contraction with cold of different substances of components on the printed board is relieved, and the reliability and the service life of the whole machine and the electronic equipment are improved. The rubber film is used as a core material for bonding the cold plate printed board, and the processing quality of the rubber film has very important influence on the reliability of the cold plate printed board.

Disclosure of Invention

The invention discloses a forming method of a cold plate printed circuit board bonding adhesive film, which aims to solve the problems of high edge burr, poor size precision and adhesion in the processing process of the cold plate printed circuit board bonding adhesive film in the appearance processing.

In order to achieve the purpose, the technical scheme adopted by the invention is that the structure for forming the circuit board adhesive film comprises two core plates and two isolation films, wherein the core plates are respectively arranged at the top and the bottom, the isolation films are arranged between the two core plates, and the adhesive film is arranged between the isolation films; the two core plates are provided with a clamp to clamp and fix the two core plates up and down.

A plurality of U-shaped elastic clamps are arranged on the periphery of the two core plates.

And the upper surfaces of the two core plates at the top are provided with heat dissipation plates.

A method for forming a cold plate printed circuit board adhesive film comprises the following steps:

step 1, accurately blanking according to the model, size and number of designed adhesive films; the blanking comprises one adhesive film, two core plates, two isolating membranes and one heat dissipation plate;

step 3, stacking the core plate, the isolating film, the adhesive film, the isolating film and the core plate from bottom to top of the raw materials in the step 1 to form a lamination, clamping and fixing the obtained lamination up and down, and covering a heat dissipation plate above the lamination;

step 3, mounting the lamination covered with the heat dissipation plate obtained in the step 2 on a milling machine tool, processing a positioning hole,

and 4, setting milling technological parameters according to the design file, milling the lamination of the positioning holes processed in the step, and removing the heat dissipation plate, the core plate and the isolating film after milling to obtain the glue film with the required model.

In step 1, the sizes of the heat dissipation plate, the core plate, the isolation film and the adhesive film are the same.

In the step 1, the core plate is an epoxy light plate with the thickness of 0.6 mm.

In step 1, the heat dissipation plate is an aluminum heat dissipation plate.

In step 2, the laminate is fixed using tape or a plurality of elastic U-shaped clamps.

Compared with the prior art, the invention has at least the following beneficial effects: the isolating film plays a role in inhibiting the adhesion of the adhesive film; the core plate can effectively inhibit edge burrs; the heat dissipation plate fully performs lamination during milling, so that the temperature of the glue film during processing is reduced, the control of adhesion phenomenon is facilitated, and the accuracy of the overall dimension of the glue film is improved; the problems of edge burrs, poor size precision and soft adhesion in the appearance processing process of the cold plate printed circuit board bonding adhesive film are effectively solved, the processing precision and quality of the cold plate printed circuit board bonding adhesive film are improved, the bonding adhesive film can be suitable for a printed cold plate board with a more complex structure and higher requirement, and the processing capacity of the cold plate printed circuit board is improved.

Drawings

FIG. 1 is a schematic view of a protective stack layer structure.

Fig. 2 is a schematic view of an aluminum cover plate.

Fig. 3 is a schematic diagram after drilling.

FIG. 4 is a schematic view of a film type.

In the attached drawing, 1-core plate, 2-isolation film, 3-adhesive film, 4-heat dissipation plate and 5-positioning hole.

Detailed Description

The invention is further explained below with reference to the figures and examples.

According to the invention, a laminated structure of six layers of four materials, namely a core plate, an isolating film, an adhesive film, the isolating film, the core plate and a heat dissipation plate, is formed in a stacking and bonding fixing mode in a fixed sequence from bottom to top, and a conventional aluminum plate is used as the heat dissipation plate and an epoxy optical plate is used as the core plate material, so that the problems of high edge burr, poor dimensional accuracy and adhesion of the adhesive film for the cold-plate printed board during contour processing can be effectively solved by matching with a milling process.

A structure for forming a bonding adhesive film of a circuit board comprises two core plates 1 and two isolating films 2, wherein the core plates 1 are respectively arranged at the top and the bottom, the isolating films 2 are arranged between the two core plates 1, and the adhesive film is arranged between the isolating films; the two core plates 1 are provided with clamps to clamp and fix the two core plates 1 up and down; a plurality of U-shaped clamps are arranged on the periphery of the two core plates 1 to form elastic clamps; the upper surfaces of the two core plates 1 at the top are provided with heat dissipation plates.

The processing flow of the cold plate printed circuit board bonding adhesive film shape processing method is as follows: blanking → stacking protection → adding a heat dissipation plate → drilling → milling → disassembling protection, namely, the top layer aluminum cover plate is covered on the front cover of the drilling step and taken down after drilling.

Step 1, blanking: accurately blanking according to the model, size and quantity of the designed adhesive film; the material is lightly taken and placed during blanking, so that the surface of the adhesive film is prevented from being scratched; the blanking comprises two core plates 1 with the same size as the glue film, two isolation films 2 and one heat dissipation plate 4; the core plate 1, the isolation film 2, the adhesive film 3, the isolation film 2, the core plate 1 and the heat dissipation plate 4 are sequentially arranged from bottom to top during plate stacking; the core plate 1 adopts an epoxy light plate, and the thickness of the epoxy light plate is 0.6 mm; the isolation film 2 plays a role in inhibiting the adhesive film 3 from adhering; the epoxy light plate plays a role in inhibiting edge burrs; the aluminum heat dissipation plate dissipates heat, reduces the temperature of the glue film during processing, is favorable for controlling the adhesion phenomenon, and is favorable for improving the overall dimension precision of the glue film.

Step 2, stacking protection: according to the blanking quantity, the protection is stacked according to the protection stack layer structure shown in fig. 1, four corners of the stack are stuck and fixed together by using adhesive tapes, and then an aluminum cover plate is covered, as shown in fig. 2.

Step 3, drilling: machining a milling type 3.2mm positioning hole 5, fixing a product to be machined on the table board of drilling equipment, setting machining parameters, then starting drilling, and turning to the next step for milling after the drilling is finished; the drilling parameters were as follows: the diameter is 3.2mm, the rotating speed is 20krpm, the falling speed is 1.02m/min, the tool withdrawal rate is 30, and the shape of the positioning hole 5 after drilling is shown in figure 3;

and 4, milling the laminated layer obtained in the step 3: installing the lamination on a milling equipment workbench, setting milling technological parameters, and starting a motor to mill; the milling process parameters are shown in table 1, and the milling process parameters are shown in fig. 4 after the milling is finished;

and 5, removing the heat dissipation plate 4, the core plate 1 and the isolation film 2 to obtain the adhesive film with the required shape.

TABLE 1 milling machining parameters

Diameter (mm)	Rotating speed (krpm)	Falling speed	XY feed
				0.6	45.0	2.0	2.0
0.8	42.0	2.0	4.0
				1.0	40.0	3.0	6.0
1.5	30.0	4.0	10.0
				2.0	28.0	6.0	16.0
2.2	26.0	7.0	18.0

Claims

1. A structure for forming a bonding adhesive film of a circuit board is characterized by comprising two core plates (1) and two isolating films (2), wherein the core plates (1) are respectively arranged at the top and the bottom, the isolating films (2) are arranged between the two core plates (1), and the adhesive film is arranged between the isolating films; the two core plates (1) are provided with clamps to clamp and fix the two core plates (1) up and down; a plurality of U-shaped elastic clamps are arranged on the periphery of the two core plates (1); the upper surface of the core plate (1) at the top is provided with a heat dissipation plate (4).

2. A method for forming a cold plate printed circuit board adhesive film is characterized by comprising the following steps:

step 1, blanking according to the model, size and number of designed adhesive films, wherein the blanking comprises one adhesive film (3), two core plates (1), two isolating films (2) and one heat dissipation plate (4);

step 3, stacking the core plate (1), the isolating film (2), the glue film (3), the isolating film (2) and the core plate (1) from bottom to top to form a lamination, clamping and fixing the obtained lamination up and down, and covering a heat dissipation plate (4) above the lamination;

step 3, mounting the lamination covered with the heat dissipation plate (4) obtained in the step 2 on a milling machine tool, processing a positioning hole (5),

step 4, setting milling technological parameters according to the design file, milling the lamination of the positioning holes (5) processed in the step 3, and removing the heat dissipation plate (4), the core plate (1) and the isolation film (2) after milling to obtain a glue film with a required model; the heat dissipation plate (4), the core plate (1) and the isolation film (2) have the same size as the adhesive film (3).

3. The method as claimed in claim 2, wherein in step 1, the core board is an epoxy board with a thickness of 0.6 mm.

4. The cold-plate PCB adhesive film forming method according to claim 2, wherein in step 1, the heat dissipation plate (4) is an aluminum heat dissipation plate.

5. The method as claimed in claim 2, wherein in step 2, the stacked layers are fixed by using an adhesive tape or a plurality of elastic U-shaped clamps.