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

A technology of circuit boards and vias, which is applied in the field of circuit board manufacturing and can solve the problem of oil loss in vias

Active Publication Date: 2013-01-16
SHENZHEN SUN & LYNN CIRCUITS
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In view of the above problems, the purpose of the present invention is to provide a method for preventing oil loss from via holes when lead-free HASL of circuit boards is used to solve the problem of excessive temperature when making circuit boards by the lead-free HASL process. The problem of oil loss through the hole

Method used

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

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Embodiment Construction

[0029] The core idea of ​​the present invention is: in the present invention, the circuit board is subjected to micro-etching and browning treatment to form a rough surface on the wall of the via hole, and then green oil is plugged in the via hole formed with the rough surface, and then baked. Board treatment, so that the green oil in the via hole can form adhesion with the rough surface of the hole wall, and in the subsequent lead-free tin spraying process, ensure that the temperature is too high to cause the green oil to expand and separate from the hole wall, resulting in dropout oil phenomenon.

[0030] In order to illustrate the idea and purpose of the present invention, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0031] See figure 1 as shown, figure 1 It is a process flow diagram of the present invention. The present invention provides a method for preventing oil loss through holes dur...

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PUM

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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...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): H05K3/24H05K3/40
Inventor 何春
Owner SHENZHEN SUN & LYNN CIRCUITS
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