A method for making PCBs that can avoid pressing and filling with insufficiency

Abstract

The invention relates to the technical field of preparation of a printed circuit board and specially relates to a preparation method of a PCB capable of preventing lamination underfill. By preparing an ink layer on an inner-layer board and carrying out solidification before lamination, and carrying out resin filling on a non-copper area first to eliminate the adverse influence of copper thicknessof the inner-layer board on the lamination process, the problems of resin underfill, lamination void and lamination surface copper sheet wrinkling during lamination of thick copper plates, and poor board thickness distribution uniformity of a multiple-layer lamination board obtained after lamination are solved; and thickness tolerance of the multiple-layer lamination board can be smaller than or equal to + / -5%, thereby meeting more strict board thickness precision requirements of the PCB. The PCB, prepared through the method, is good in board thickness uniformity, and is smaller than or equalto + / -5% in thickness tolerance; and for thick copper boards (>=40Z), interlayer resin filling is full, and the problems of lamination void and lamination surface copper sheet wrinkling do not occur,thereby laying a good foundation for subsequent processes of drilling and film pasting and the like.

Description

technical field [0001] The invention relates to the technical field of manufacturing printed circuit boards, in particular to a method for manufacturing PCBs that can avoid lamination and filling. Background technique [0002] When producing non-secondary power thick copper plate (≥4OZ) products, it is normal to have a large area of ​​copper-free area in the design of the inner layer circuit, but the thickness difference between the superimposed area and the non-superimposed area (≥140um) will directly affect the lamination time. Uniformity of pressure distribution and filling performance of resin flow. The thicker the bottom copper of the PCB board, the denser the circuit and the more layers. In the lamination process, the problems of insufficient resin filling, lamination voids, wrinkling of the copper skin on the lamination surface and poor uniformity of the thickness distribution of the lamination board The more prominent, these problems will directly lead to the scrapp...

AI Technical Summary

Problems solved by technology

[0003] The present invention aims at problems such as insufficient resin filling and uneven board thickness after lamination for thick copper plates (≥4OZ) in the lamination process in the existing PCB production mode, and provides a method that can avoid insufficient resin filling during lamination. Production method of full PCB with uneven board thickness after lamination