MARKING METHOD FOR RESIN-SEALED TYPE SEMICONDUCTOR DEVICE

摘要

PURPOSE:To realize a simplified re-marking technique by a method wherein a coating of an liquid epoxy resin containing a pigment that colors under laser ivadiation is provided on a surface whereon marking has already been accomplished and a prescribed region in the once-marked surface experiences remarking when exposed to a laser beam. CONSTITUTION:To a once-marked surface 5 of a resin-sealed type semiconductor device main body, a coating is applied containing a liquid epoxy resin 7 containing a pigment to color under laser illumination. A prescribed region of the once-marked surface 5 is subjected to laser illumination for re-marking. For example, an aniline black-based Co-Mn-Ni alloy dyestuff is a pigment capable of coloring when exposed to heat generated under laser ivadiation. A layer not less than 20mum thick of a liquid epoxy resin 7 containing approximately 0.5% said pigment is laid by brushing or screen printing on a once- marked surface 5 and is exposed to the temperature of 150 deg.C for curing for not shorter than 3 hours. The once-marked surface 5 is then subjected to laser ivadiation for the correction of a product ranking mark to 'BQ'.