Thin Film Growth of Germanium Selenides from PECVD of GeCl4 and Dimethyl Selenide

Plasma enhanced chemical vapor deposition (PECVD) of germanium selenide thin films from germanium tetrachloride and dimethyl selenide was studied to determine the viability of these reagents for thin film deposition. Germanium tetrachloride and alkylselenides were selected as candidates for these reactions due to their lower toxicities and higher availabilities compared to the more typical substitutes: germane and hydrogen selenide in the formation of germanium selenides. Dimethyl selenide was used successfully for the deposition of germanium selenides. Variation in film stoichiometry was observed by the modification of reactant gas flow ratios. Relative mass flow rates were varied in order to determine their effect on germanium chalcogenide deposition, and the effect of these flow rate modifications on the film thickness, structural properties, and composition are reported.