Activated reactive laser deposition of GeO, films

Abstract

Amorphous GeO, optical thin films were grown in an oxygen ambient on heated Si substrates using the technique of pulsed laser deposition. The application of a partially ionized oxygen plasma generated by passing the plume through a ring electrode facilitated stoichiometric film growth in low O2 partial pressures. Emission spectroscopy of the plume revealed an enhancement in the ionic and neutral excited Ge species. The concentration of excited neutral and ionic oxygen atoms also significantly increased when the ring electrode was activated at P(O.-J>lO mTorr. Coupling the results of the film property measurements with the emission studies suggested that the presence of 0 atoms near the substrate surface during tilm growth was more critical in promoting oxidation than the gas phase process in the plume. The low-pressure conditions that were utilized to deposit stoichiometric film growth identified the appropriate conditions to produce uniform films over a large area that may be suitable for waveguide fabrication