Thin films of amorphous germanium-carbon and germanium-nitrogen alloys prepared by activated reactive evaporation

Abstract

Thin films of amorphous germanium-carbon (a-Gel _XCx) and amorphous germanium-nitrogen (a-Ge1-xNx) alloys have been prepared by activated reactive evaporation. Germanium was evaporated from a resistively heated tungsten basket through a methane (or nitrogen) plasma. The films thus prepared were characterized for their structúral, optical and electrical properties. The presence of Ge-C and Ge-N vibration modes in the films was revealed in the IR spectra. The films exhibited sharp absorption edges with the value of optical gap varying from 1.3 to 1.6 eV and a thermally activated electrical conduction with an activation energy value ranging from 0.66 to 0.78 eV. © 1990 Elsevier Sequoia S.A.