EXTENDED UNDER-BUMP METAL LAYER FOR BLOCKING ALPHA PARTICLES IN A SEMICONDUCTOR DEVICE

摘要

An integrated circuit (IC) has an under-bump metal (UBM) pad disposed between a solder bump and a semiconductor portion of the IC. A UBM layer is disposed between the solder bump and the semiconductor portion and includes the UBM pad and a UBM field. The UBM pad has a contact perimeter formed with the solder bump. The UBM pad extends beyond the contact perimeter a sufficient distance to block alpha particles emitted from the surface of the solder bump from causing an upset event in the semiconductor portion. The UBM field is separated from each UBM pad by a gap extending from the UBM pad to the UBM field so as to electrically isolate the UBM field from the UBM pad.