Nozzle beam deposition of SiO2 films

Abstract
SiO2 films were deposited on 2 in. Si(100) wafers at an oxygen pressure of 102 Pa and substrate temperature of 300 °C using a nozzle beam deposition technique. High purity SiO2 grains were evaporated in a graphite crucible at a temperature of 1500 °C. The evaporated species were then ejected through a nozzle and were partially ionized by electron bombardment prior to deposition. The index of refraction and infrared absorption spectrum of the films were found to depend strongly on the ionization current and acceleration voltage applied to the beam. The thickness and refractive index of the film are uniform over the entire 2 in. wafer if the applied acceleration voltage is less than 1 kV.