阅读说明：本技术 一种盲埋孔印制电路板及其制作方法 (A kind of blind buried via hole printed circuit board and preparation method thereof ) 是由 刘国汉 杨杰 于 2019-08-12 设计创作，主要内容包括：本发明公开了一种盲埋孔印制电路板,包括多层覆铜板、设置在相邻两层覆铜板之间的粘接片,覆铜板内填充有树脂柱,树脂柱的末端覆盖有第二金属层,第一金属层与第二金属层相接,粘接片内填充有铜浆,铜浆与第二金属层相接。还包括一种盲埋孔印制电路板的制作方法,通过粘结片上盲埋孔对应处开孔,在孔内塞铜浆,粘接片与覆铜板在压合过程中,铜浆与金属膜烧结在一起,实现层间互连,粘接片用铜浆塞孔前贴合一层PET膜进行保护。本技术方案可以减少压合次数,提高生产效率,可以实现较多次盲埋孔结构的印制电路板,还可以减少最外层镀铜次数、降低外层铜厚,可制作更小的线宽/间距,提高电路板的线路密集度。(The invention discloses a kind of blind buried via hole printed circuit boards, including multilayer copper-clad plate, the adhesive sheet being arranged between adjacent two layers copper-clad plate, resin column is filled in copper-clad plate, the end of resin column is covered with second metal layer, the first metal layer connects with second metal layer, it is starched in adhesive sheet filled with copper, copper slurry connects with second metal layer.It further include a kind of production method of blind buried via hole printed circuit board; pass through buried via hole blind on bonding sheet corresponding position aperture; it is starched in hole internal plug copper; adhesive sheet and copper-clad plate are during the pressing process; copper slurry is sintered together with metal film; realize interlayer interconnection, one layer of PET film of fitting is protected before adhesive sheet copper slurry consent.The technical program can reduce pressing number, production efficiency is improved, the printed circuit board of relatively multiple blind buried-hole structure may be implemented, outermost layer copper facing number can also be reduced, reduce outer layer copper thickness, smaller line width/spacing can be made, the route closeness of circuit board is improved.)

1. a kind of blind buried via hole printed circuit board characterized by comprising multilayer copper-clad plate (1) is arranged in adjacent two layers copper-clad plate Between adhesive sheet (2), be provided with the first aperture (11) in the copper-clad plate, be provided in the adhesive sheet and the first aperture (11) corresponding second aperture (21), first aperture (11) is interior to be filled with resin column (14), in first aperture (11) It is provided between wall and resin column (14) the first metal layer (12), the end of the resin column (14) is covered with second metal layer (13), the first metal layer (12) is connected with second metal layer (13), and metallic object is filled in second aperture (21) (22), the metallic object (22) is connected with second metal layer (13).

2. a kind of production method of blind buried via hole printed circuit board characterized by comprising

Copper-clad plate processing:

A1 drills in copper-clad plate designated position, carries out metalized to aperture, then clogs aperture with resin, in aperture Resinous terminal cover metal film again, route is then made in copper-clad plate；

A2, the copper-clad plate that other layers are handled according to step A1；

Adhesive sheet processing:

B1, one layer of PET film is pasted on adhesive sheet surface, then drills in designated position, according to preliminary drying parameter after hole internal plug copper slurry Preliminary drying is carried out, PET film is then torn；

B2, the adhesive sheet that other layers are handled according to step B1；

Circuit board processing:

C1, by copper-clad plate, bonding sheet in order lamination then according to setting pressing parameter pressed to obtain multilayer circuit board；

C2, finished product is obtained after multilayer circuit board is carried out the processing of printed board route.

3. the production method of blind buried via hole printed circuit board according to claim 2, it is characterised in that: copper in the step B1 Slurry is the mixture of copper powder, silver powder and epoxy resin.

4. the production method of blind buried via hole printed circuit board according to claim 2, it is characterised in that: in the step B1 PET film with a thickness of 25-40um.

5. the production method of blind buried via hole printed circuit board according to claim 2, it is characterised in that: in the step B1 The being stained with property of PET film is 4-10g/25mm.

6. the production method of blind buried via hole printed circuit board according to claim 2, it is characterised in that: pre- in the step B1 Baking parameter is 40-60 ° of preliminary drying temperature, preliminary drying time 30-60min.

7. the production method of blind buried via hole printed circuit board according to claim 2, it is characterised in that: pressed in the step C1 Conjunction parameter be 1-3 ° of heating rate/min, 210-230 ° of maximum temperature reached, retention time 1.5-2.5h, pressure 40-60kg/ cm2。

Technical field

The present invention relates to printed wiring board processing and fabricating field, it is specifically related to a kind of blind buried via hole printed circuit board and its system Make method.

Background technique

As electronic product develops to miniaturization, high density, high-precision, printed wiring board is proposed accordingly higher It is required that having there is blind buried via hole printed circuit board to achieve the purpose that intensively to be routed.Existing blind buried via hole printed circuit board layer and layer it Between conducting connection be by drilling after pressing, then device to hole carries out metallization and realizes interlayer interconnection, blind multiple blind for same layer Buried via hole plate needs are repeatedly pressed, primary per blind one step press, and plate is even resulted in the meeting aging after repeatedly pressing Fail when subsequent assembly welding, and after repeatedly pressing multiple hole metallization, surface copper thickness can also thicken therewith cause it is subsequent Circuit etching is difficult, can not do the intensive plate of route, run in the opposite direction with the function of the highly dense property of blind buried via hole.The prior art is blind to bury Hole press number general control 3 times (containing) hereinafter, and line width/spacing is required, if to realize blind 4 printings of same layer Circuit board needs to press 4 times, not can guarantee reliability.

Summary of the invention

To solve the above-mentioned problems, the object of the present invention is to provide one kind can be reduced pressing number, increase the blind buried via hole number of plies, And the blind buried via hole printed circuit board and preparation method thereof for guaranteeing reliability.

The technical solution adopted by the present invention is that:

A kind of blind buried via hole printed circuit board, comprising: multilayer copper-clad plate, the bonding being arranged between adjacent two layers copper-clad plate Piece is provided with the first aperture in the copper-clad plate, the second aperture corresponding with the first aperture is provided in the adhesive sheet, described It is filled with resin column in first aperture, the first metal layer, the resin are provided between the first aperture inner wall and resin column The end of column is covered with second metal layer, and the first metal layer connects with second metal layer, is filled in second aperture Copper slurry, the copper slurry connect with second metal layer.

A kind of production method of blind buried via hole printed circuit board characterized by comprising

Copper-clad plate processing:

A1 drills in copper-clad plate designated position, carries out metalized to aperture, then clogs aperture with resin, opening Resinous terminal in hole covers metal film again, and route is then made in copper-clad plate；

A2, the copper-clad plate that other layers are handled according to step A1；

Adhesive sheet processing:

B1, one layer of PET film is pasted on adhesive sheet surface, then drills in designated position, according to preliminary drying after hole internal plug copper slurry Parameter carries out preliminary drying, then tears PET film；

B2, the adhesive sheet that other layers are handled according to step B1；

Circuit board processing:

C1, by copper-clad plate, bonding sheet in order lamination then according to setting pressing parameter pressed to obtain multilayer circuit Plate；

C2, finished product is obtained after multilayer circuit board is carried out the processing of printed board route.

Further, copper is starched as the mixture of copper powder, silver powder and epoxy resin in the step B1.

Further, in the step B1 PET film with a thickness of 25-40um.

Further, the being stained with property of PET film is 4-10g/25mm in the step B1.

Further, preliminary drying parameter is 40-60 ° of preliminary drying temperature, preliminary drying time 30-60min in the step B1.

Further, in the step C1 press parameter be 1-3 ° of heating rate/min, 210-230 ° of maximum temperature reached, Retention time 1.5-2.5h, pressure 40-60kg/cm2.

The beneficial effects of the present invention are:

The present invention is starched, adhesive sheet and copper-clad plate are being pressed by blind buried via hole corresponding position aperture on bonding sheet in hole internal plug copper In the process, copper slurry be sintered together with metal film, realize interlayer interconnection, adhesive sheet with copper starch consent before be bonded one layer of PET film into Row protection avoids adhesive sheet other parts from being starched by extra copper and pollutes.

The technical program can reduce pressing number, improve production efficiency, and the print of relatively multiple blind buried-hole structure may be implemented Circuit board processed can also reduce outermost layer copper facing number, reduce outer layer copper thickness, can make smaller line width/spacing.Maximumlly The demand for meeting blind buried via hole printed circuit board high-density wiring improves the route closeness of circuit board.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of eight layers of blind buried via hole printed circuit board in the present invention；

Fig. 2 is the process principle figure of copper-clad plate in the present invention；

Fig. 3 is the process principle figure of adhesive sheet in the present invention；

Fig. 4 is the flow chart of the blind buried via hole method for manufacturing printed circuit board of the present invention.

Specific embodiment

To explain the technical content, the achieved purpose and the effect of the present invention in detail, below in conjunction with embodiment and cooperate attached Figure is explained.

It is as shown in Figure 1 a kind of blind buried via hole printed circuit board of the invention, comprising: four layers of 1 He of copper-clad plate stacked gradually Three layers of adhesive sheet 2 between adjacent two layers copper-clad plate are set, the first aperture 11 is provided in copper-clad plate, is provided in adhesive sheet Second aperture 21 corresponding with the first aperture 11, the first aperture 11 are interior filled with resin column 14,11 inner wall of the first aperture and resin The first metal layer 12 is provided between column 14, the end of resin column 14 is covered with second metal layer 13, the first metal layer 12 and Two metal layers 13 are connected, and are filled with metallic object 22 in the second aperture 21, metallic object 22 is connected with second metal layer 13, the present embodiment Middle the first metal layer 12, second metal layer 13 are copper film, and metallic object 22 is copper slurry, and ingredient is all copper powder/silver powder and asphalt mixtures modified by epoxy resin The mixture of rouge.

The production method for being illustrated in figure 4 a kind of blind buried via hole printed circuit board of the invention, with eight layers of same layer shown in FIG. 1 For the blind buried via hole printed circuit board manufacturing process of blind 4 structures, making step are as follows:

Copper-clad plate processing: as shown in Fig. 2, drilling after copper-clad plate a1/ copper-clad plate a2 sawing sheet, by hole metallization, to mesoporous metal Filling holes with resin is carried out after change, copper facing again on resin after filling holes with resin, then to make L2 sandwich circuit to be laminated, copper facing is for protecting on resin Demonstrate,prove the subsequent connection area on bonding sheet.

Production route is to be laminated after copper-clad plate a3/ copper-clad plate a4 sawing sheet, and copper-clad plate a3 etches the route of L5/L6, covers copper Plate a4 etches the route of L7.

Adhesive sheet processing:

As shown in figure 3, pasting one layer of PET film after bonding sheet b1/ bonding sheet b2 sawing sheet, starched after drilling in hole internal plug copper, then Preliminary drying processing is carried out, can be pressed after PET film is torn after preliminary drying with copper-clad plate as multilayer circuit board.Preferably, in the present embodiment The ingredient of copper slurry is the mixture of copper powder/silver powder and epoxy resin, there is stronger electric conductivity, can also use the gold of other compositions Belong to slurry；The size of boring aperture is in the same size with corresponding blind buried via hole aperture；Because bonding sheet is generally relatively thin, only 0.1-0.2mm, PET film can not only guarantee that copper is starched full when filling in copper slurry, but also can have copper slurry residual to avoid non-jack position, it is ensured that the thickness of protrusion Degree is sintered more reliable with copper face.

In the present embodiment PET film with a thickness of 25-40um, be viscosity 4-10g/25mm；Preliminary drying parameter need to be less than adhesive sheet Tg value prevents adhesive sheet from solidifying in advance and does not flow after guaranteeing copper slurry drying-plate, 40-60 ° of preliminary drying temperature in the present embodiment, when preliminary drying Between 30-60min.

Circuit board processing:

It by above-mentioned copper-clad plate a1-a4, bonding sheet b1-b3 lamination in order, is put into Special purpose pressing machine and is pressed into 8 laminates, bond The copper slurry assist side bonding processes of on piece are sintered with bilevel copper sheet and are combined together, and realize interlayer interconnection. Press parameter are as follows: 1-3 ° of heating rate/min, the highest temperature need to reach 210-230 °, retention time 1.5-2.5h, pressure 40- 60kg/cm2。

It is sequentially completed the normal flow of the printed boards route such as drilling, pattern transfer, welding resistance, surface treatment, sharp processing processing A kind of blind buried via hole printed circuit board of blind 4 structures of eight layers of same layer can be obtained in journey.

In conclusion the present invention is starched by blind buried via hole corresponding position aperture on bonding sheet in hole internal plug copper, adhesive sheet and copper is covered During the pressing process, copper slurry is sintered together plate with metal film, is realized and is bonded one layer before interlayer interconnection, adhesive sheet starch consent with copper PET film is protected, and is avoided adhesive sheet other parts from being starched by extra copper and is polluted.

The technical program can reduce pressing number, improve production efficiency, and the print of relatively multiple blind buried-hole structure may be implemented Circuit board processed can also reduce outermost layer copper facing number, reduce outer layer copper thickness, can make smaller line width/spacing.Maximumlly The demand for meeting blind buried via hole printed circuit board high-density wiring improves the route closeness of circuit board.

The above description is only an embodiment of the present invention, is not intended to limit the scope of the invention, all to utilize this hair Equivalents made by bright specification and accompanying drawing content are applied directly or indirectly in relevant technical field, similarly include In scope of patent protection of the invention.