To meet the level requirements on printed circuit board(PCB),it is necessary to use the modified semi-additive process(mSAP)and ultra-thin copper foil with an attachment of 3 μm or less.Our 3 μm mSAP process uses a window opening process for laser drilling processing.To ensure the alignment accuracy,during high-precision exposure,one needs to grab the inner target for alignment.This article verifies that it is feasible to directly ablate the target with CO2 laser on 3 μm copper foil by using the characteristics of the heat accumulation effect in CO2 laser processing.And the laser stack hole design and laser processing parameters in the ablation target area are key factors affecting the target ablation result.Through research,the optimal stack hole design scheme and optimal laser processing parameters have been output.It has been verified that CO2 laser directly ablating target processing can meet the requirements of target alignment for high-precision exposure by 100％for both concave and convex targets.
high density interconnector(HDI)printed circuit board(PCB)modified semi-additive process(mSAP)ultra-thin copper foilCO2 laserdirectly ablating targetheat accumulation effect
NETL
NSTL
万方数据
