Initial Stage of Laser-Induced Selective Chemical Vapor Deposition of Silicon

Spatially selective chemical vapor deposition has been achieved by ArF excimer laser (193 nm) irradiation through a metal mask in a Si2H6 + He gas mixture. The selective deposition kinetics has been found to be controlled by a nonthermal process and has been explained in terms of the Langmuir-Hinshelwood mechanism. Both surface migration of adsorbed radicals and desorption of reaction products appear to be enhanced with the laser irradiation, leading to a selective nucleation of silicon.