LASER-INDUCED DEPOSITION OF ONE-MICRON-SIZE POLYSILICON LINES FROM MONO AND TRISILANE

High-resolution deposition of polysilicon lines has been performed on various silicon-silicon-dioxide-silicon multilayer substrates locally heated by means of a CW argon-ion laser emitting at several wavelengths around 0.5-mu-m in the presence of silane or trisilane gas. The deposition kinetics and the morphology of the silicon microstructures have been investigated as a function of laser beam power and gas pressure at various scanning speeds of the laser spot. Polysilicon lines between 1 and 2-mu-m in width have been written under specific processing conditions. These lines have been characterized using both a scanning electron microscope and a focused ion beam system. The deposition rate was found to be significantly faster with trisilane than with silane and limited by a thermally activated process occurring in the adsorbed layer.