Fast thermal kinetic growth of silicon dioxide films on InP by rapid thermal low-pressure chemical vapour deposition

Abstract

Silicon dioxide films were deposited onto InP substrates in the ranges of 350-550 degrees C temperature, and 3-15 Torr pressure by means of the rapid thermal low-pressure chemical vapour deposition (RTLPCVD) technique. SiO2 films were deposited using a variety of Ox: SiH4 ratios in the range of 5:1-50:1, and deposition rates of 15-50 nm s-1. The high temperature and high rate deposition was obtained without creating any damage to the InP substrate surface, and resulted in highly densified SiO2 layers with good thickness control and low stress. The main parameters of the as-deposited and annealed films, such as deposition rate, density, refractive index, wet and dry etch rates, stresses, film microstructure, and the SiO2/InP interface quality are reported. These parameters were studied as a function of the process variables, which include deposition time, temperature, pressure, O2:SiH4 ratio, gas flow rates and chamber geometry.