Patent ID: 7115514
Filing Date: 2006-10-03
Classification: B23K,Y10S

Abstract:
1. A method of removing material from a surface of a semiconductor wafer comprising the steps of: generating an initial wavelength-swept-with-time optical pulse in an optical pulse generator; amplifying the initial pulse; compressing the amplified pulse to a duration of less than about 10 picoseconds, to generate a compressed optical pulse; and applying the compressed optical pulse to the wafer surface, to remove material from the wafer surface; wherein the step of amplifying is done with a fiber-amplifier and the step of compressing is done with an air-path between gratings compressor, and the initial wavelength-swept-with-time optical pulses is between about 10 picoseconds and about 3 nanoseconds and the compressed optical pulse has a sub-picosecond duration and an energy density on the surface is between about 2 and about 10 times an optical ablation threshold of the surface.