CN101888749A - Process for laminating PCB with internal through-hole structure - Google Patents

Abstract

The invention discloses a process for laminating a printed circuit board (PCB) with an internal through-hole structure. The process comprises the following steps of: (1) drilling through holes on an upper core plate and a lower core plate to be laminated; (2) performing metallization plating on the through holes; (3) paving a release film and an aluminum sheet on the upper surface of the upper core plate from the top to the bottom in turn; paving the release film and the aluminum sheet on the lower surface of the lower core plate from the top to the bottom in turn; and arranging a prepreg between the upper core plate and the lower core plate; (4) laminating; and (5) removing the aluminum sheet; using the aluminum sheet in a drilling process of subsequent processing; and tearing the release film. In a laminating process of manufacturing the PCB, the aluminum sheet and the release film are used as auxiliary materials for laminating so that resin in the through holes cannot overflow to the surface of the PCB in the laminating process, a process of eliminating residual resin on the surface of the PCB by repeatedly grinding by using a grinding machine is saved, production cost is greatly reduced, production processes are saved, production efficiency is improved and working space is saved.

Description

A kind of pcb board process for pressing with internal through-hole structure

Technical field

The present invention relates to a kind of process for pressing of pcb board, specifically at the process for pressing of pcb board with internal through-hole (IVH) structure.

Background technology

Along with progress of science and technology, the number of plies of pcb board is more and more, and pcb board is by central layer and semi-solid preparation lamination synthesis type.At present, pcb board with internal through-hole (IVH) structure, when carrying out multilayer pressing manufacturing, between two central layers, prepreg is set, in the pressing process, resin on the prepreg can be pressed against in the via on the central layer, after continuing pressing, resin in the via via of can gushing out is outer and cover in the pcb board surface, needs repeatedly to grind with elimination through grinder to cover resin on the pcb board surface, and the Copper Foil on central layer and surface thereof is vulnerable to infringement in the process of grinding, so that scrap, and, influenced follow-up serviceability because machinery equipment and artificial factor can't be ground totally sometimes.In addition, costing an arm and a leg of milling apparatus strengthened production cost.In the existing processing technology, some only lays a release film on the central layer surface, directly pressing then, and effect is relatively poor; Some lays two-layer Copper Foil in the central layer upper and lower surface, and after between this two-layer Copper Foil prepreg being set, carry out pressing, though solved the problem that the resin in the via overflows to a certain extent, but in the pressing process, still there is resin to be extruded out, and the expense costliness, the thickness of slab uniformity is wayward.

Summary of the invention

The technical problem to be solved in the present invention provides a kind of production efficiency height, the pcb board process for pressing with internal through-hole structure that cost is low.

In order to solve the problems of the technologies described above, this is bright takes following technical scheme:

A kind of pcb board process for pressing with internal through-hole structure may further comprise the steps:

(1) last central layer to be laminated and following central layer are bored via;

(2) to the via plating of metallizing;

(3) lay a release film, an aluminium flake from bottom to up successively at the upper surface of last central layer, lay a release film, an aluminium flake from top to bottom successively at the lower surface of following central layer, and prepreg is set between last central layer and following central layer;

(4) pressing;

(5) shift out aluminium flake, this aluminium flake is used for the drilling operating of following process, and remove release film.

As the improvement to such scheme, the thickness of aluminium flake is 0.15mm～0.20mm.

The present invention is by the improvement to existing technology, in the pressing process, adopt aluminium flake and release film as the pressing auxiliary material, utilize resiliency that aluminium flake provides and to the adaptivity of central layer, effectively suppressed overflowing of resin in the via, saved after the pressing and pcb board to have been transferred to the grinding carried out on the special-purpose milling apparatus repeatedly operation with the resin of eliminating the pcb board surface, effectively shortened work flow, a manufacturing cycle is compared with existing technology and has saved about 10 minutes, improved production efficiency greatly, also saved special-purpose milling apparatus has been installed, provided cost savings greatly and the space.The aluminium flake that the pressing process is used is the aluminium flake that uses in the drilling operating of following process, uses in the also extensible drilling operating that turns back to following process after the pressing, does not need to buy in addition aluminium flake, effectively reduces cost.And, pcb board surface Copper Foil can not sustained damage owing to need not grind repeatedly through milling apparatus.In addition, the resin in the via can not overflow, and end product quality is better, and the plate face of central layer is smooth, and the production board thickness evenness after the processing is better.

Description of drawings

Accompanying drawing 1 is the Product Status schematic diagram before the pressing of the present invention; Accompanyingdrawing 2 is the product cross-sectional view after the pressing of the present invention; Accompanyingdrawing 3 is the Product Status schematic diagram before the prior art pressing.

Embodiment

For the ease of those skilled in the art's understanding, the invention will be further described below in conjunction with accompanying drawing, need to prove, below the content mentioned be not to be limitation of the invention.

Shown in accompanyingdrawing 1,2, a kind of pcb board process for pressing with internal through-hole IVH structure comprises step as described below: (1) bores via 3 to last central layer to be laminated 1 and followingcentral layer 2; (2) to via 3 plating of metallizing; (3) lay a release film 4, analuminium flake 5 from bottom to up successively at the upper surface of lastcentral layer 1, lay a release film 4, analuminium flake 5 from top to bottom successively at the following lower surface ofcentral layer 2, andprepreg 6 is set at lastcentral layer 1 and 2 of following central layers, thisprepreg 6 can be according to actual needs, be provided with one, two or three, do not enumerate one by one at this; (4) pressing; (5) shift outaluminium flake 5, thisaluminium flake 5 is used for the drilling operating of following process, and remove release film 4.Wherein, the thickness of aluminium flake is 0.15mm～0.20mm.Following process comprises the boring undertaken by the technology of prior art, heavy copper, plating, outer graphics transfer etc. finally making the pcb board finished product of IVH structure, is prior art because follow-up processing all adopts, therefore, does not remake in detail at this and to give unnecessary details.In addition, the brill via ofstep 1 of the present invention,step 2 to via metallize plating, and the pressing working procedure of step 4 in the technology used, the pressure that relates to as pressing in the step 4, temperature etc. all adopt routine techniques known in those skilled in the art, do not remake in detail at this and to give unnecessary details, promptly adopt common pcb board processing technology can realize production of the present invention.

Need to prove that the central layer that the present invention mentions can not enumerated at this one by one for four layers, eight layers or 20 layers or more even levels, be provided with according to client's actual needs.

Embodiment one, lastcentral layer 1 and followingcentral layer 2 are 4 layers of central layer, lay a release film 4, analuminium flake 5 successively at the upper surface of lastcentral layer 1, lay a release film 4, analuminium flake 5 successively at the following lower surface ofcentral layer 2, lastcentral layer 1 and 2 of following central layers are provided with aprepreg 6, the thickness of aluminium flake is 0.15mm, carries out pressing, is 8 laminates after the pressing.

Embodiment two, lastcentral layer 1 and followingcentral layer 2 are 8 layers of central layer, lay a release film 4, analuminium flake 5 successively at the upper surface of lastcentral layer 1, lay a release film 4, analuminium flake 5 successively at the following lower surface ofcentral layer 2, lastcentral layer 1 and 2 of following central layers are provided with twoprepregs 6, the thickness of aluminium flake is 0.18mm, carries out pressing, is 16 laminates after the pressing.

Embodiment three, lastcentral layer 1 and followingcentral layer 2 are 24 layers of central layer, lay a release film 4, analuminium flake 5 successively at the upper surface of lastcentral layer 1, lay a release film 4, analuminium flake 5 successively at the following lower surface ofcentral layer 2, lastcentral layer 1 and 2 of following central layers are provided with threeprepregs 6, the thickness of aluminium flake is 0.20mm, carries out pressing, is 48 laminates after the pressing.

Compared with prior art, disclosed technical scheme utilizes aluminium flake and release film as the auxiliary material in the pressing process, resin in the pressing process on the prepreg enters in the central layer via, resin in the central layer via can not spill into the central layer surface, saved in the milling apparatus of after the pressing central layer being transferred to special use and ground the operation of overflowing the resin on central layer surface with elimination repeatedly, be that the present invention compares with existing technology and reduced operation, production procedure is shortened, improve production efficiency greatly, saved production cost.

Enumerate the present invention below and adopt aluminium flake and release film and available technology adopting Copper Foil and prepreg relatively, all calculate by market price as the cost of pressing auxiliary material.

Specification is that every of the release film of 640 * 400mm * 40um is 2.04 yuan; Specification is that every of the aluminium flake of 508mm * 340mm * 0.2mm is 2.00 yuan; Specification is that every of the Copper Foil of 640 * 400mm * 12um is 2.81 yuan; Specification is that every of the prepreg of 508 * 340mm is 2.25 yuan.

As shown in Figure 1, the present invention only need adopt 2 aluminium flakes and 2 release films to get final product as the pressing auxiliary material.Because aluminium flake is to utilize the aluminium flake that uses in the drilling operating of following process among the present invention, this aluminium flake still can return in the drilling operating of following process and use after the pressing, therefore, do not need additionally to buy aluminium flake, the pressing subsidiary materials cost is 2.04 yuan/* 2=4.08 yuan.

As shown in Figure 3, available technology adopting Copper Foil and prepreg are the pressing auxiliary material, because the upper surface at last central layer is laid twoCopper Foils 7 and aprepreg 6, lower surface at following central layer is laid twoCopper Foils 7 and aprepreg 6, therefore, the pressing subsidiary materials cost is: 2.81 yuan/open * 4+2.25 yuan/* 2=15.74 yuan, (15.74-4.08)/15.74 * 100%=74.1%.

Be not difficult to find out that by above data the cost of pressing auxiliary material of the present invention is compared with the cost of pressing auxiliary material in the prior art and descended about 70%, effectively reduces production cost.

In addition, though only also have in the prior art and respectively lay the technology that a release film promptly carries out pressing at the upper surface of last central layer and the lower surface of following central layer, the subsidiary materials cost of pressing is the same with the present invention, but resin can spill into the central layer surface after the pressing like this, need carry out grinding step repeatedly, increased extra production cost, and the copper on the central layer surface after the pressing is in uneven thickness.

The technology of above prior art all needs central layer forwarded in the special-purpose milling apparatus after pressing grinds repeatedly, to eliminate the resin on central layer surface.And the present invention can not spill into the central layer surface owing to resin in the pressing process, having saved takes central layer away grinds in the milling apparatus repeatedly to eliminate the operation of central layer surface resin, compare with the existing technology of making pcb board, the present invention has shortened the process-cycle, manufacturing cycle has been saved about 10 minutes,, improved efficient.More saved special-purpose milling apparatus has been installed, saved space and cost.Just need general 1,000,000 yuans as one four grinders, every of ceramic brush wheel just needs 1.5 ten thousand yuan in the grinding-material, and four grinders just need four ceramic brush wheels, and expense is relatively more expensive.The present invention need not install special-purpose grinder, and the electricity charge, labour cost also decrease.This shows, adopt disclosed technical scheme after, not only shortened manufacturing process, improved production efficiency, also saved production cost greatly.

Claims (2)

1. pcb board process for pressing with internal through-hole structure may further comprise the steps:

(1) last central layer to be laminated and following central layer are bored via;

(2) to the via plating of metallizing;

(3) lay a release film, an aluminium flake from bottom to up successively at the upper surface of last central layer, lay a release film, an aluminium flake from top to bottom successively, and between last central layer and following central layer prepreg is set at the lower surface that descends central layer;

(4) pressing;

(5) shift out aluminium flake, this aluminium flake is used for the drilling operating of following process, and remove release film.

2. the pcb board process for pressing with internal through-hole structure according to claim 1 is characterized in that: the thickness of described aluminium flake is 0.15mm～0.20mm.

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