Patent ID: 7015064

Claim:
A wafer level method of marking back surfaces of integrated circuit devices, the method comprising: providing a wafer having a plurality of flip chip style integrated circuit devices, the wafer having an active surface and a back surface, the active surface having a plurality of electrically conductive pads; applying a mount tape to the back surface of the wafer, the mount tape being arranged to support the wafer and including a optically opaque backcoat layer, a pigment layer and a mount layer; curing the backcoat layer such that the backcoat layer is affixed to the back surface of the wafer and such that the backcoat layer covers the entire back surface of each of the integrated circuit devices; exposing selected portions of the mount tape to light at a frequency that releases pigments from the pigment layer to thereby mark the backcoat layer to thereby mark the back surface of the integrated circuit devices; dicing the wafer to define a multiplicity of singulated flip chip style integrated circuits dice supported by the mount tape; and separating the singulated integrated circuits dice from the mount tape while leaving the backcoat layer affixed to the back surfaces of the integrated circuit dice, whereby the cured backcoat layer forms an optically opaque protective coating that covers the entire back surface of each integrated circuit device and is suitable for preventing light from striking the back surface of the integrated circuit device and the pigments that mark the backcoat layer include markings desired for the integrated circuit device.