RAMAN AND ELECTRICAL CHARACTERIZATIONS OF A-GAAS1-XNX THIN-FILMS GROWN ON C-SI(P) SUBSTRATES BY N-2 REACTIVE SPUTTERING

In this paper, we report on electrical properties and Raman scattering of amorphous GaAs1-xNx deposited on p-type crystalline silicon (c-Si( p)) substrates. The aim of this study is the investigation of the diel ectric character of GaAs1-xNx in view of its applications in MIS struc tures. The ''compound'' GaAs1-xNx is obtained by reactive RF sputterin g of a GaAs target. The electrical characteristics of the a-GaAs1-xNx/ c-Si(p) heterostructures present a MIS-like structure behaviour with s ome imperfections. Raman scattering points out that a-GaAs1-xNx is a w ide gap material which is formed by the substitution of arsenic by nit rogen in the GaAs network. For substitution ratios below 25-30%, the m aterial obtained would be an alloy whose vibrational behaviour is a si ngle mode. Beyond 30%, it would be in a very inhomogeneous phase, infa ct polyphased, and would present a phase of hexagonal origin (GaN).