Method for circuit manufacture of ultra-thin inner-layer board

Abstract

The invention discloses a method for the circuit manufacture of an ultra-thin inner-layer board. The method aims at manufacturing circuit patterns of an ultra-thin inner-layer board of a multilayer circuit board and comprises the following steps of: carrying out pattern exposure on a first face of the ultra-thin inner-layer board, and etching the face; laminating the first face of the ultra-thin inner-layer board with a core board adjacent to the first face; carrying out pattern exposure on a second face of the ultra-thin inner-layer board, and etching the face; and laminating the second face of the ultra-thin inner-layer board with a core board adjacent to the second face. According to the method, a manner of single-face etching and step-by-step laminating is adopted, when a single face is etched, a dry film on the other face is subjected to overall exposure so as to reserve all copper-clad layers, regions of which both faces have no copper-clad layers can not exist when the first face of the ultra-thin inner-layer board is etched, and thus, the thin core boards are prevented from fracturing or being broken down; and when the second face is etched, the etching is carried out after the first face is laminated with the core board adjacent to the first face, so that the ultra-thin inner-layer board can have enough strength when the second face is etched.

Description

technical field [0001] The invention relates to a method for manufacturing a multi-layer circuit board, more specifically a method for manufacturing an ultra-thin inner layer circuit board. Background technique [0002] The production process of the multilayer printed circuit board is formed by laminating the inner layer board circuit with the dielectric layer. When the inner core board is too thin (generally ≤25μm), it is easy to penetrate the substrate when etching, especially for the board without glass fiber in the core board. [0003] When etching on both sides, for the inner core board of ≤25μm, if the copper on both sides of the front and back of a certain pattern is etched away, these places are easy to penetrate the base material due to the spray of liquid medicine, resulting in cracks or gaps in the inner layer board And other issues. [0004] Therefore, it is necessary to develop a new manufacturing method to avoid the problem that the substrate is penetrated by...

AI Technical Summary

Problems solved by technology

[0003] When etching on both sides, for the inner core board of ≤25μm, if the copper on both sides of the front and back of a certain pattern is etched away, these places are easy to penetrate the base material due to the spray of liquid medicine, resulting in cracks or gaps in the inner layer board And other issues

[0004] Therefore, it is necessary to develop a new manufacturing method to avoid the problem that the substrate is penetrated by the liquid medicine when the ultra-thin inner layer is etched.

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