Influence of hydrogen partial pressure on growth and properties of nanocrystalline SiC by magnetron sputtering

¹ LPMC, Faculté des Sciences de Tunis, Campus Universitaire El Menzeh, 1060 Tunis, Tunisia
² Faculté des Sciences de Bizerte, 7021 Zarzouna, Bizerte, Tunisia
³ IEMN, avenue Poincaré, BP 69, 59652 Villeneuve d'Ascq Cedex, France
⁴ SIFCOM, CNRS UMR 6176, 6 boulevard Maréchal Juin, 14050 Caen, France
⁵ LPMC, Faculté des Sciences d'Amiens, 33 rue Saint-Leu, 80039 Amiens Cedex, France

Corresponding author: heloise.colder@iemn.univ-lille1.fr

Received: 30 March 2006
Revised: 30 June 2006
Accepted: 10 July 2006
Published online: 6 October 2006

Abstract

Hydrogenated nanocrystalline silicon carbide (nc-SiC:H) thin films were prepared by reactive magnetron sputtering. Deposition was achieved in a plasma of argon (Ar) and an hydrogen (H₂) gas mixture with various H₂ dilution percentages (10–80% H₂) at a fixed substrate temperature of 500 °C. In order to describe the local bonding and the relative proportion of the different complexes formed during growth, the films were investigated by means of Fourier Transform Infrared absorption and Raman spectroscopy. Other structural features were analyzed by AFM measurements, electron diffraction and high resolution transmission electron microscopy observations. Optical and electrical properties of the films were also characterized. This study shows that hydrogen dilution plays an important role on the microstructure of the films as well as on their properties. The highest refractive index was obtained for a 60% ratio of hydrogen in the plasma and the highest dark conductivity found was 2.03 × 10⁻⁴ Ω⁻¹ cm⁻¹. A close relationship between the Si-H bond content and the conductivity is confirmed.