A method for reducing the air bubble rate of QFP-packaged integrated circuit chip conformal paint coating

Abstract

The invention discloses a method for reducing the air bubble rate of QFP packaged integrated circuit chips coated with anti-corrosion paint. The surface of the chip body is formed with a coating surface, and an exhaust channel is formed between two adjacent groups of pin mechanisms. The pin mechanism is composed of several groups of chip pins, and the adjacent two groups of chip pins are equidistantly arranged. QFP package The conformal paint coating method of the chip is as follows: step 1: pre-coating of chip pins intermittent circuit; step 2: static exhaust outflow treatment; step 3: continuous spraying treatment. The present invention adopts discontinuous circuit spraying, pre-coats the pins around the four sides of the chip, reserves the four corners of the chip to exhaust, and after static buffering, the three-proof paint is siphoned to the bottom of the chip, and then the entire surface of the chip is coated with a continuous circuit , can effectively improve the bubble rate of QFP packaging.

Description

technical field [0001] The invention relates to the technical field of conformal paint coating for QFP packaging, in particular to a method for reducing the bubble rate of conformal paint coating for QFP packaging integrated circuit chips. Background technique [0002] QFP packaging means square flat packaging technology. Generally, large-scale or very large-scale integrated circuit chips adopt this packaging form, and the number of pins is generally more than 100. The distance between pins of the CPU chip implemented by this package is very small, and the pins are very thin, so there is a one-time pass problem in spraying. Conformal paint is a commonly used protective coating in the PCBA processing industry and can be used to protect QFP packages. The components are protected from the erosion of water and salt spray in the environment. Conformal paint has good high and low temperature resistance performance. After curing, it forms a transparent protective film, which has e...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for reducing the rate of air bubbles in the conformal paint coating of QFP-packaged integrated circuit chips, which solves the problem that the conformal paint will flow into the bottom of the chip from the four sides of the chip at the same time, and the air at the bottom of the chip has no discharge channel to form bubbles

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