Laser cutting of aluminium stripes for debugging integrated circuits

The laser cutting of aluminium stripes on a semiconductor integrated circuit chip is investigated using a nitrogen-laser-pumped dye laser with a 12-ns pulse duration of 0.51-μm wavelength. Stripe cutting, without damaging the underlayers, is performed using an aperture projection method in which laser power density is uniformly distributed and edge resolution is sharp. The effects of stripe and SiO/SUB 2/ layer thicknesses, laser power, and aperture size on the removal of stripes are presented. In addition, the thermal effects on device characteristics are calculated. This technique is shown to be effective as a debugging tool in VLSI development, either at the research stages or at the production stages.