Nanostructured Hydrogenated Silicon Films by Hot-Wire Chemical Vapor Deposition: the Influence of Substrate Temperature on Material Properties

Author(s) V.S. Waman1 , M.M. Kamble1 , M.R. Pramod1 , A.M. Funde1 , V.G. Sathe2 , S.W. Gosavi3 , S.R. Jadkar3

1 School of Energy Studies, University of Pune, Pune, 411 007, India

2 UGC-DAE-CSR, University Campus, Khandawa Road, Indore, 452 017, India

3 Department of Physics, University of Pune, Pune, 411 007, India

Issue Volume 3, Year 2011, Number 1, Part 3
Dates Received 04 February 2011, in final form 18 June 2011, published online 23 June 2011
Citation V.S. Waman, M.M. Kamble, M.R. Pramod, et al., J. Nano- Electron. Phys. 3 No1, 590 (2011)
PACS Number(s) 81.15.Gh, 61.05.c,,
Key words Hot wire chemical vapor deposition, Nanocrystalline silicon thin films, Structural properties (8) , Optical properties (17) , Electrical properties (14) .
Thin films of hydrogenated nanocrystalline silicon are prepared at reasonably higher deposition rates (9-13 Å/s) by indigenously fabricated hot-wire chemical vapor deposition system at various substrate temperatures (Ts). In this paper we report extensively studied structural, optical and electrical properties of these films by Fourier transform infrared (FTIR) spectroscopy, low angle X-ray diffraction (low angle XRD), micro-Raman spectroscopy and UV-Visible spectroscopy. The low angle XRD and micro-Raman spectroscopy analysis indicate amorphous-to-nanocrystalline transition occurred at Ts = 300 °C. It is observed that volume fraction of crystallites and its size increases with increase in Ts. The low angle XRD study also shows nc-Si:H films with well-identified lattice planes of (111) orientation. In addition, it is observed from the FTIR spectroscopy that the hydrogen is incorporated in the film mainly in Si-H2 and (Si-H2)n complexes. The nc-Si:H films with low hydrogen content (< 4 at. %) and wide band gap (1.83-1.89 eV) and low refractive index (< 3) is useful for various device applications.