Patent ID: 6727458
Filing Date: 2004-04-27
Classification: B23K,H01L,Y10S,Y10T

Abstract:
An energy-efficient, laser-based method for processing target material having a reflectivity and a specified dimension in a microscopic region without causing undesirable changes in electrical or physical characteristics of at least one material surrounding the target material, the method comprising:generating a laser pulse train utilizing a laser having a wavelength at a repetition rate; optically amplifying at least a portion of the pulse train to obtain an amplified pulse train wherein each of the amplified pulses has a temporal power density distribution, a sharp rise time, a pulse duration and a fall time; and delivering and focusing a plurality of closely-spaced pulses of the amplified pulse train to the target material wherein the power density distribution of the plurality of closely-spaced pulses is sufficiently high and the rise time is fast enough to efficiently couple laser energy to the target material and reduce reflectivity of the target material, and wherein the pulse duration of each of the amplified pulses is in the range of several picoseconds to about 10 nanoseconds and the fall time is rapid enough to prevent the undesirable changes to the at least one material surrounding the target material wherein the target material is processed in a thermal manner.