Negative, design method for same, and circuit substrate made of same

Abstract

The invention relates to a negative, a design method for the negative, and a circuit substrate made of the negative. The negative includes a first negative; the fist negative includes a first composing area provided with a plurality of circuit board patterns and comprising a first shielding area, a first light-transmittable area and a first waste area; the first shielding area has the shape and the size identical to those of a to-be-electroplated area on a first surface of a circuit board; the first waste area is provided with a first shielding compensation area spaced from the first shielding area, and other part (except the first shielding compensation area) of the first waste area is light-transmittable; and if the first composing area is equally divided into a plurality of first design areas, the total area of the first shielding area and the first shielding compensation area in any one of the first design areas is equal to the total area of the first shielding area and the first shielding compensation area in another one of the first design areas. The electroplated layer thickness of the circuit substrate has high uniformity.

Description

technical field [0001] The invention relates to the technical field of circuit boards, in particular to a negative film designed for an exposure and development process, a design method of the negative film and a circuit substrate made using the negative film. Background technique [0002] According to the number of conductive circuit layers, circuit boards include single-sided circuit boards, double-sided circuit boards and multi-layer circuit boards. The production of double-sided circuit boards and multilayer circuit boards mostly involves electroplating processes. Taking the double-sided hard board as an example, its electroplating includes placing the circuit substrate formed with via holes and conductive lines in an electroplating tank for electroplating until the thickness of the copper layer on the wall of the via hole and the conductive lines reaches the thickness specified by the customer. Taking the double-sided circuit board of mobile phone as an example, its pr...

AI Technical Summary

Problems solved by technology

[0004] However, since the layout of negatives is based on the principle of saving raw materials as much as possible, if the shape of the circuit board to be manufactured is irregular, multiple circuit board graphics may be distributed in a non-linear array on the same negative

Assuming that the film is divided into multiple design areas, the area of ​​the light-shielding area in different areas may be different, resulting in the area to be plated in different areas of the subsequent circuit substrate, such as the walls of all via holes in the circuit substrate of a mobile phone. It may be different from the total area of ​​all buttons or the total area of ​​the conductive lines on the double-sided hard board and the walls of all via holes. During the electroplating process, the corresponding current densities in different design areas will be inconsistent, which will lead to inconsistencies in the circuit board. The thickness of the coating in the area with a large area to be plated is quite different from that in the area with a small area to be plated, which seriously affects the quality of the circuit board

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