Method of preventing via hole from oil dropping in lead-free HASL process of circuit board

Abstract

The invention discloses a method of preventing a via hole from oil dropping in the lead-free HASL (Hot Air Solder Leveling) process of a circuit board, which comprises the steps of etching, microetching and brownification, volcanic ash scrubbing, green oil jacking, solder resisting and lead-free HASL. According to the method, a microetching and brownification procedure is added after the etching, and a hole wall is subjected to micro coarsening to increase the adhesion of jacking green oil to the hole wall, thereby achieving the purpose of preventing the subsequent lead-free HASL technology from resulting in the oil dropping of the via hole due to high temperature. Compared with the prior art, the method solves the problem of oil dropping of the via hole in the green oil jacking in the lead-free HASL technology, the technology is simple, and the product quality is improved effectively.

Description

Technical field:

[0001] The invention relates to a circuit board manufacturing technology, in particular to a method for preventing oil loss through holes when the circuit board is manufactured by a lead-free tin-spraying process, and is mainly aimed at a PCB board with a ball grid array structure (BGA). Background technique:

[0002] During the production process of circuit boards, processes such as gold plating and immersion gold are required, and the temperature of circuit boards needs to be controlled within 100°C during the above-mentioned treatment process, so that when the circuit boards are plugged with green oil, the ink can withstand other processes. The temperature range will not be separated from the hole wall, so there will be no oil loss through the hole at this time.

[0003] With the rapid development of electronic products, users have put forward higher requirements for the circuit boards of electronic products, and the PCB board of the ball grid array struc...

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