Nitrogen influence on the properties of the /spl alpha/-C films and /spl alpha/-C/Si heterojunction

Abstract

An effect of nitrogen on the optical and electrophysical properties of /spl alpha/-C films and /spl alpha/-C/Si heterojunction has been studied. Nitrogen was introduced into a gas mixture within the range of 0 to 45% during the process of chemical-vapour deposition of /spl alpha/-C films. the substantial variations of optical and electrophysical properties of /spl alpha/-C films and /spl alpha/-C/Si heterojunction at different nitrogen concentration were observed. In particular, the character of observed changes has opposite behaviour at nitrogen concentration range of 0-20% and 20-45%. The electron paramagnetic resonance and Auger spectrometry of these samples do not exhibit the nitrogen content in the films. The Raman spectroscopy reveals a diamond phase in the films. An improvement of the diode parameters of /spl alpha/-C/Si heterojunction and changing of permittivity and carrier mobility as a result of nitrogen content in the gas mixture were obtained from I-V and C-V measurements.