Abstract
Nitrided surfaces and composition gradients in thin films exhibit interesting mechanical, electrical and optical properties. Therefore, silicon (Si) thin films were prepared by electron beam evaporation and nitrided by an inductively coupled rf plasma. The effects of successive plasma processing power on structural and optical properties as well as electrical resistivity were examined by different characterization techniques. The Si thin films were transformed gradually into nitrides compound thin films and the amount of nitrogen in the film increased with increasing the rf processing power. The Si
nitrided films showed structural, optical and electrical properties that depend on the nitriding power. Increasing the rf plasma processing power caused amorphization, reduced the thickness, increased transmittance, increased resistivity and decreased the reflectance of the Si films. The electrical resistivity increased about eight orders of magnitude when the sample nitrided at 500 W. Different optical band gap were determined indicating the presence of different competing phases
in the same film. The decrease in refractive index with plasma treatment power is attributed to the possible change in the bucking density as well as to the increase in the band gap.
Keywords
Si thin films, Rf plasma nitriding, Structural properties, Electrical resistivity, Optical properties.
Citation
S. H. MOHAMED, M. RAAIF, A. M. ABD EL-RAHMAN, E. R. SHAABAN, Physical properties of silicon films nitrided at different rf plasma-processing powers, Optoelectronics and Advanced Materials - Rapid Communications, 4, 12, December 2010, pp.2108-2113 (2010).
Submitted at: Nov. 8, 2010
Accepted at: Nov. 29, 2010