Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/4977
Title: Effects of Si incorporation on the structural change of a-BₓSi₁₋ₓ alloy films
Authors: Ong, C. W.
Chik, K. P.
Wong, H. K.
Subjects: Boron silicides
Amorphous semiconductors
Microstructure
XRD
Absorption spectra
Infrared spectra
CVD
Chemical bonds
Solid clusters
Issue Date: 15-Nov-1993
Publisher: American Institute of Physics
Source: Journal of applied physics, 15 Nov. 1993, v. 74, no. 10, p. 6094-6099.
Abstract: Amorphous BₓSi₁₋ₓ films can be easily prepared by low‐pressure chemical vapor deposition over the whole range of x from 0 to 1. In this article, the structural change of BₓSi₁₋ₓ films (0≤x≤1) was studied by x-ray diffraction and infrared (IR) absorption experiments. It was found that these two methods are complementary to each other. X-ray results showed that when x is decreased, there is a gradual transition from the α-B structure, through the SiB₄ structure, to the amorphous silicon structure. The transition to α-Si structure is complete at a surprisingly high boron concentration of around 40 at. %. Infrared data also revealed an unexpected result—that the presence of boron suppresses the formation of Si—H types of bonds in high silicon content films, in strong contrast to films prepared by the glow discharge method. Another interesting feature of the IR absorption spectra is the predominance of an absorption band, related to the presence of boronlike icosahedral clusters, in all films with boron concentration to as low as 17.6 at. %. Such clusters may be responsible for the easy formation of an impurity band lying about 0.2 eV above the valence mobility edge, as observed by transport measurements of boron-doped α-Si films prepared by low-pressure chemical vapor deposition.
Rights: © 1993 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in C. W. Ong, K. P. Chik & H. K. Wong, J. Appl. Phys. 74, 6094 (1993) and may be found at http://link.aip.org/link/?jap/74/6094.
Type: Journal/Magazine Article
URI: http://hdl.handle.net/10397/4977
DOI: 10.1063/1.355171
ISSN: 0021-8979 (print)
1089-7550 (online)
Appears in Collections:AP Journal/Magazine Articles

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