Patent ID: 7348516

Claim:
A laser-based processing method of removing target material from selected electrically conductive link structures of redundant memory or integrated circuitry, each selected link structure including a link having opposite side surfaces and top and bottom surfaces, the opposite side surfaces being separated by a distance that defines a link width, at least the side and bottom surfaces being positioned adjacent passivatian structure material in a circuit fabricated on a substrate, comprising: directing a laser output pulse for incidence on a selected link structure, the laser output pulse being in the form of a unitary pulse characterized by a laser spot, an average power, and a laser pulse temporal power profile; the laser spot having a spot size at a laser spot position on the selected link structure, the spot size being larger than the link width; the laser pulse rernpoial power profile having rising and falling edges, having a pulse duration, and characterized by a power spike, the power spike having a spike duration that is substantially shorter than the pulse duration, a peak power that is more than about 10% over the average power of the laser output pulse, and a time of occurrence that is coincident with the rising edge; the laser pulse temporal power profile, after the coincidence of the occurrence of the power spike and the rising edge, declining to and holding relatively steady at a level for a time before the falling edge; and the peak power, spike duration, and time of occurrence of the power spike cooperating to establish for the laser output pulse a specially tailored laser pulse power profile that effects severing of the selected link structure while not causing appreciable damage to the substrate or the passivation structure material positioned adjacent the side and bottom surfaces.