Studies on Ge/CeO2 thin film system using positron beam and Raman spectroscopy

THIN SOLID FILMS

卷:406

Article

Rao, GV ; Amarendra, G ; Viswanathan, B ; Kanakaraju, S ; Balaji, S ; Mohan, S ; Sood, AK

关键词: amorphous materials;    germanium;    positron spectroscopy;    Raman scattering;    defects;   

DOI  :  10.1016/S0040-6090(02)00056-1

来源: Elsevier

【 摘 要 】

Positron beam and Raman spectroscopic studies are reported on a Ge/CeO2 thin film system grown on a Si substrate. The variation of the Doppler line shape S-parameter, as a function of positron beam energy, shows a pronounced maximum corresponding to the Ge-region of as-grown film, while no equivalent feature is seen in the sample annealed at 773 K. The Raman spectrum of the as-grown film exhibits a broad band, as opposed to a sharp peak observed for the annealed sample, Based on the correlated evidence from the two measurements, it is concluded that the Ge layer in the as-grown sample is amorphous, containing a large concentration of structural vacancies. Isochronal annealing measurements of the lineshape parameter in the temperature range of 300 to 773 K indicate a rather continuous transformation of amorphous Ge to the crystalline state. (C) 2002 Elsevier Science B.V. All rights reserved.

【 授权许可】

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