RELIABLE WAFER-LEVEL CHIP-SCALE PACKAGE SOLDER BUMP STRUCTURE IN A PACKAGED SEMICONDUCTOR DEVICE

摘要

A wafer level chip scale package (WLCSP) includes a packaged semiconductor device with a plurality of solder bump pads, patterned passivation regions above each of the solder bump pads, a patterned under bump metallization (UBM) region on each of the solder bump pads and the passivation regions, a polyimide region over a portion of the UBM regions and the passivation regions, solder bumps formed on each of the UBM regions, and encapsulation material surrounding the semiconductor die except for at least a portion of each of the solder bumps.