Wafer inspection system reduces scrap by up to 7 times

摘要

In semiconductor wafer manufacturing, lithographic processing techniques result in layers of oxide, polysilicon, or metal that may be unevenly deposited across the surface of the wafer. Before further lithographic processing can occur, chemical mechanical polishing (CMP) is used to planarize these layers. A polishing head is rotated across the wafer to even out the irregular wafer surface. After each polishing step, the wafer must be examined to ensure that no residual material remains on the wafer surface.