High Quality Low Temperature Deposition of Alumina Thin Films by Means of the Expanding Thermal Plasma-CVD

摘要

Expanding thermal plasma (ETP-CVD) deposition of high density (2.9 g·cm~(-3)) carbon free alumina films at a deposition temperature of 80°C is reported, deposited with the precursor pulsing technique. In depth study of the films is done by means of various characterization techniques as a function of the precursor off time. A remarkable increase in the refractive index from 1.50 to 1.63 is reported with the increase in precursor off time from 1.1 s to 7.5 s respectively. It is observed from the mass spectrometry results that the increasing precursor off time facilitates the combustion of carbon related groups from the alumina films as well from the plasma leading to dense carbon free alumina films.