CN201797646U

CN201797646U - PCB structure to improve the difference in dimensional stability of multilayer boards

Info

Publication number: CN201797646U
Application number: CN2010205396110U
Authority: CN
Inventors: 吴小连; 叶锦荣
Original assignee: Shengyi Technology Co Ltd
Current assignee: Shengyi Technology Co Ltd
Priority date: 2010-09-21
Filing date: 2010-09-21
Publication date: 2011-04-13
Anticipated expiration: 2020-09-21

Abstract

The utility model provides an improve PCB structure of multiply wood dimensional stability difference, it includes: the inner core board comprises a plurality of layers of copper foils and a plurality of inner prepregs arranged among the copper foils at intervals, the inner prepregs and the outer prepregs comprise reinforcing materials and insulating resin layers coated on two sides of the reinforcing materials, and the reinforcing materials are glass fiber paper. The utility model discloses an improve PCB structure of multiply wood dimensional stability difference adopts the fine paper of glass to be its reinforcing material, compares in the fine cloth of glass of conventional use, and this fine paper longitude and latitude of glass is unanimous to the CTE to the harmomegathus is unanimous, can improve the dimensional stability problem that multilayer PCB leads to because of the anisotropy difference of traditional prepreg greatly, effectively avoids the inaccurate problem of counterpoint that appears in the multilayer PCB manufacture process, improves the processing qualification rate, and can reduce this type of multilayer PCB's comprehensive cost by a wide margin.

Description

Improve the PCB structure of multi-layer sheet dimensional stability difference

Technical field

The utility model relates to the printed wiring board technical field, relates in particular to a kind of PCB structure of improving multi-layer sheet dimensional stability difference.

Background technology

The all materials of printed wiring board mainly are as reinforcing material with glass fabric in the industry at present, its model difference different through the weft yarn number or used yarn, cause CTE (thermal coefficient of expansion) difference of sheet material on warp, latitude direction, thereby make used core material of multi-layer PCB and prepreg in multi-layer sheet pressing process, warp, broadwise can produce different contractions.And the contraction difference of warp, latitude direction can directly cause the contraposition between each layer of multi-layer sheet difference to occur, and especially in high multilayer, the accurate contraposition of each interlayer is the emphasis of high multi-layer PCB production control always in the one step press process.

Along with electronic product develops to high multilayer, the accurate contraposition of PCB interlayer is proposed higher requirement, the traditional existing warp of glass cloth prepreg, latitude direction harmomegathus is inconsistent will to be difficult to satisfy such high request.

The utility model content

The purpose of this utility model is, a kind of PCB structure of improving multi-layer sheet dimensional stability difference is provided, and can improve the problem of multi-layer PCB dimensional stability difference greatly, avoids the inaccurate problem of contraposition that occurs in the multi-layer PCB manufacturing process.

To achieve these goals, the utility model provides a kind of PCB structure of improving multi-layer sheet dimensional stability difference, it comprises: core material, be laminated with the outer prepreg of core material both sides and be laminated with Copper Foil on the outer prepreg, core material comprises that several layers of Copper Foil and several are located at the interior prepreg between Copper Foil at interval, this inside and outside prepreg includes reinforcing material, is coated with the insulating resin layer of being located on the reinforcing material two sides, and this reinforcing material is a glass paper.

Described reinforcing material is 25～105g/m ²Glass paper.

The resin content of described inside and outside prepreg is 75～95%.

Described core material two opposite outer is a Copper Foil, and outer prepreg covers on the Copper Foil in this two outside.

The beneficial effects of the utility model: the PCB structure of improving multi-layer sheet dimensional stability difference of the present utility model, adopting glass paper is its reinforcing material, glass cloth compared to the routine use, this glass paper warp, broadwise CTE unanimity, thereby harmomegathus unanimity, can improve the dimensional stability problem that multi-layer PCB causes because of the anisotropy difference of traditional prepreg greatly, effectively avoid the inaccurate problem of the contraposition that occurs in the multi-layer PCB manufacturing process, improve passing rate of processing, and can significantly reduce the integrated cost of such multi-layer PCB.

In order further to understand feature of the present utility model and technology contents, see also following about detailed description of the present utility model and accompanying drawing, yet accompanying drawing only provide with reference to and the explanation usefulness, be not to be used for the utility model is limited.

Description of drawings

Below in conjunction with accompanying drawing,, will make the technical solution of the utility model and other beneficial effect apparent by embodiment of the present utility model is described in detail.

In the accompanying drawing,

Fig. 1 improves the structural representation of inside and outside prepreg in the PCB structure of multi-layer sheet dimensional stability difference for the utility model;

Fig. 2 is the part plan structural representation of reinforcing material in the utility model (glass paper).

Embodiment

Below in conjunction with accompanying drawing the utility model is described in detail.

The PCB structure of improving multi-layer sheet dimensional stability difference of the utility model one embodiment, it comprises: core material, be laminated with the outer prepreg of core material both sides and be laminated with Copper Foil (not shown) on the outer prepreg, core material comprises that several layers of Copper Foil and several are located at the interior prepreg between Copper Foil at interval.The core material two opposite outer is a Copper Foil, and outer prepreg covers on the Copper Foil in this two outside.As shown in Figure 1, this inside and outside prepreg includes reinforcing material 1, is coated with the insulating resin layer 2 that is located on reinforcing material 1 two sides, and this reinforcing material 1 is a glass paper.

Described reinforcing material 1 adopts 25～105g/m ²Glass paper, as shown in Figure 2, the architectural characteristic that described glass paper has is loose, astaticism distributes can be eliminated the warp that the existing warp of glass cloth, broadwise CTE difference caused, the difference of broadwise dimensional stability with it as reinforcing material, is beneficial to the accurate contraposition of interlayer of the multi-layer PCB of making.Using the resin content of the inside and outside prepreg that this kind glass cloth makes is 75～95%.

When inside and outside prepreg of the present utility model is made, use glass paper as reinforcing material 1, apply insulating resin in its surface, then in baking oven behind the high-temperature baking semi-solid preparation, resin forms insulating resin layer 2 on reinforcing material 1 two sides, be 75～95% inside and outside prepreg thereby make resin content.Core material is made in interior prepreg and Copper Foil pressing that employing makes, these core material two outsides are Copper Foil, on outer prepreg pressing core material, pressing Copper Foil on the prepreg outside promptly makes the described PCB structure of improving multi-layer sheet dimensional stability difference again.Wherein core material can be had a sandwich construction, adopts promptly that prepregs are pressed between the several layers of Copper Foil at interval in several pieces.

As process a 10 layers of pcb board, and this plate uses core material to be 6mil 2/2 in having now, joins originally to be: 2*1080, and glass cloth prepreg is 2116, needs core material is compensated before processing, penalty coefficient is a warp-wise-1.6, broadwise-0.9; After boring processing, still there is a certain proportion of contraposition to be forbidden phenomenon, need do for supplement.And adopt 10 layers of pcb board that improve the PCB structure fabrication of multi-layer sheet dimensional stability difference of the present utility model, use 1 25g/m ²The interior prepreg that glass paper is made, RC% (resin content) is 75～95%, can replace 2 1080 glass cloth semi-solid preparations to produce the core material of 6mil 2/2, has avoided the difference through the CTE of, broadwise, simultaneously, uses 1 50g/m ²The outer prepreg that glass paper is made can replace 2 2116 glass cloth prepregs in this structure, RC% is 75～95%, after the multi-layer PCB board moulding, the difference of the CTE of warp, broadwise has also been eliminated, be in the whole multi-layer PCB board structure, all use glass paper to replace former used glass cloth, thoroughly eliminated the otherness of dimensional stability of warp, the broadwise of multi-layer PCB board, core material compensates in advance by original penalty coefficient, boring processing behind the lamination, the accurate contraposition of hole potential energy of interlayer, qualification rate reaches 100%.And cost has bigger competitive advantage than original structure.

In sum, the PCB structure of improving multi-layer sheet dimensional stability difference of the present utility model, adopting glass paper is its reinforcing material, glass cloth compared to the routine use, this glass paper warp, broadwise CTE unanimity, thereby harmomegathus unanimity, can improve the dimensional stability problem that multi-layer PCB causes because of the anisotropy difference of traditional prepreg greatly, effectively avoid the inaccurate problem of the contraposition that occurs in the multi-layer PCB manufacturing process, improve passing rate of processing, and can significantly reduce the integrated cost of such multi-layer PCB.

The above; for the person of ordinary skill of the art; can make other various corresponding changes and distortion according to the technical solution of the utility model and technical conceive, and all these changes and distortion all should belong to the protection range of the utility model claim.

Claims

1. A PCB structure for improving the difference in dimensional stability of multilayer boards, characterized in that it comprises: an inner core board, an outer prepreg coated on both sides of the inner core board and a copper foil clad on the outer prepreg, The inner core board includes several layers of copper foil and several inner prepregs arranged at intervals between the copper foils. Both the inner and outer prepregs include reinforcing materials and insulating resin layers coated on both sides of the reinforcing material. The reinforcing material is glass fiber Paper.

2 . The PCB structure for improving the difference in dimensional stability of multilayer boards according to claim 1 , wherein the reinforcing material is glass fiber paper of 25-105 g/m ² .

3 . The PCB structure for improving the difference in dimensional stability of multilayer boards according to claim 1 , wherein the resin content of the inner and outer prepregs is both 75% to 95%.

4. The PCB structure for improving the difference in dimensional stability of multi-layer boards according to claim 1, wherein the inner core board is made of copper foil on the opposite two outer sides, and the outer prepreg is laminated on the copper foil on the two outer sides .