Alkaline etching process of printed circuit board

Abstract

The invention relates to an alkaline etching process of a printed circuit board, belonging to the technical field of production of the circuit board. The alkaline etching process of the printed circuit board comprises the steps of: firstly, controlling the temperature of an alkaline etching solution within a range from 40 DEG C to 60 DEG C and controlling the PH value within 8.0-8.8; then adding chloride ions with the content of 130-170 g / l in the alkaline etching solution; then adding bivalent copper ions with the content of 120-170 g / l in the alkaline etching solution; then adding thiourea with the content of 0.04-0.07 g / l into the alkaline etching solution; then removing a mask image from the to-be-etched PCB (Printed Circuit Board); then cleaning the to-be-etched PCB with pure water for twice and then drying the PCB in an absorbing manner by using a clean cloth material; then blow-drying the PCB by using a blower; then detecting whether the PCB is damaged; then alkaline-etching the PCB which is qualified through check by using the alkaline etching solution to remove the unused copper surface portion so as to form wiring; then scrubbing and washing the alkaline-etched PCB with ammonia water for twice; then scrubbing and washing the PCB with pure water for twice; after finishing washing, drying the PCB in an absorbing manner by using the clean cloth material; then blow-drying the PCB with the blower; and then checking whether the PCB is damaged.

Description

Technical field [0001] The invention relates to an alkaline etching process for printed circuit boards, and belongs to the technical field of circuit board manufacturing. Background technique [0002] In the manufacturing process of printed circuit boards, as a method of forming wiring, the circuit image on the film is transferred to the copper clad laminate to form a resist or electroplating mask image. The anti-electroplating mask image we are discussing here is used in the pattern electroplating process, that is, a negative phase image is formed on the copper clad laminate with a protective anti-corrosion material, so that the required image is a copper surface, and these copper surfaces pass After the cleaning treatment, copper plating and other metal protective layers are plated, and then the anti-plating mask image is removed for alkaline etching. At present, the printed circuit board (PCB) industry is developing in the direction of high precision (line width and line spac...

AI Technical Summary

Problems solved by technology

At present, the printed circuit board (PCB) industry is developing towards high precision (line width and line spacing of 0.05-0.08 mm), high density (more than 4 wires arranged between two pads), and alkaline etching The technical requirements for the line width tolerance of the process are getting higher and higher, and the existing alkaline etching process has technical problems such as slow etching rate and serious side etching, which seriously restricts the development of the printed circuit board (PCB) industry