Patent ID: 6703318
Filing Date: 2004-03-09
Classification: H01L

Abstract:
A method of chemical mechanical polishing (CMP) a first material on a second material of a semiconductor die, said method comprising:defining a plurality of substantially identical semiconductor dies on a semiconductor wafer, said wafer having a planar surface, and wherein said plurality of dies are separated from one another by a scribe line; forming a layer of said second material on said planar surface wherein said layer of said second material having a top surface, substantially parallel to said planar surface; forming a layer of said first material on said top surface, wherein said layer of said first material varying in a height direction above said top surface; forming a mask across the wafer, wherein said mask having a plurality of locations with each location having differing density of gap to pillar ratio, which is proportional to the height of said first material above said top surface; anistropically etching said first material through each gap of said mask, across the wafer, wherein each gap is etched by the same amount in the height direction; and using CMP to planarize said first material to said top surface across the wafer.