Patent ID: 8253066

Claim:
A laser-based method of removing a target link structure of a circuit fabricated on a substrate without causing undesirable damage to the substrate, any dielectric layers between the target link structure and the substrate, or link structures adjacent to the target link structure, the target structure being in a set of link structures, at least some link structures being separated by a pitch of less that 2 microns, the method comprising: generating a sequence of laser pulses at a first repetition rate of greater than about 1 MHz utilizing a seed laser having a first predetermined wavelength; optically amplifying at least a portion of the sequence of laser pulses to obtain an amplified sequence of laser pulses comprising a burst of output pulses within a burst envelope shape; controlling pulse characteristics whereby the burst envelope shape comprises a desired envelope shape; and delivering and focusing pulses of the burst onto the target link structure during relative motion of the substrate and the focused pulses, substantially all output pulses of the burst having a pulse duration of less than about 1 nanosecond, corresponding to pulse power densities in the range of at least 10 9 W/cm 2 to less than about 10 12 W/cm 2 at the target link structure, and a wavelength of about 1.2 microns or less, wherein the power density of the focused pulses is low enough to avoid undesirable damage, and wherein interaction between the laser pulses and the material is a thermal process.