Patent ID: 7723642

Claim:
A laser-based system for 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 the target link structure, the target link structure being in a set of link structures, at least some link structures in the set of link structures being separated by a pitch of less than 2 μm, the system comprising: means, including a seed laser, for generating a sequence of laser pulses at a repetition rate of greater than about 1 MHZ, the seed laser having a first predetermined wavelength; means for optically amplifying at least a portion of the sequence of laser pulses to obtain an amplified sequence of output pulses; means for controllably selecting at least a portion of the amplified sequence of output pulses based on at least one of position and velocity information to synchronize the target link structure with laser beam position during motion of the substrate relative to the laser beam, wherein the means for controllably selecting includes either an acousto-optic modulator or an electro-optic modulator; and means for delivering and focusing pulses of the amplified sequence of output pulses onto the target link structure during the relative motion, substantially all pulses of the amplified sequence of output pulses having a pulse duration greater than about 10 picoseconds and less than about 100 picoseconds, corresponding pulse power densities in the range of at least about 10 9 W/cm 2 to less than about 10 13 W/cm 2 over a focused spot diameter of 1.5 microns or less at the target link structure, and a wavelength of about 1.2 microns or less.