REINFORCEMENT OF SOLDER BALL

摘要

PURPOSE: A reinforcement of a solder ball is provided by forming an under-fill layer under the solder ball in the fabrication process of a chip scale package(CSP) so as to improve an adhesion(attachment) reliability, so that the other under-fill process may be required no more in the assembling processes thereafter, i.e., a productivity increases. CONSTITUTION: A reinforcement method contains the following steps: a step to coat a resin on a wafer surface to be attached to the solder-ball, for increasing the adhesion strength of the solder-ball in the CSP device attaching the solder-ball as an external terminal; a step to remove the resin in the region excluding the area under the solder-ball; a step to clean the resin which remains without being removed; and a step to perform a cold cure for assuring the characters of a layer qualities.