Optical absorption in /spl mu/c-Si:H films induced by oxygen

Author

Kunii, T. ; Kiriyama, T. ; Mori, K. ; Yoshida, N. ; Nonomura, S.

Author_Institution

Graduate Sch. of Eng., Gifu Univ., Japan

Volume

2

fYear

2003

fDate

18-18 May 2003

Firstpage

1683

Abstract

Extra optical absorption in /spl mu/c-Si:H films at photon energy of 0.7/spl sim/1.2 eV caused by impurity has been studied by resonant photothermal bending spectroscopy. The extra absorption increases by thermal annealing in air. And, the absorption coefficient was not changed by carbon contamination in /spl mu/c-Si:H film. Thus, we propose that the origin of the extra absorption is localized states related to oxygen impurity in the film. In addition, the extra optical absorption has negative temperature coefficient at the temperature region of 25/spl sim/150/spl deg/C. And, the energy level of the localize state caused by the oxygen exists around 0.7 eV from band edge. From these results, we proposed that the localized state exists in the grain boundaries including amorphous Si structure.

Keywords

absorption coefficients; amorphous semiconductors; annealing; elemental semiconductors; hydrogen; localised states; noncrystalline defects; noncrystalline structure; photothermal spectroscopy; semiconductor thin films; silicon; 25 to 150 degC; Si-H films; Si:H; absorption coefficient; amorphous Si structure; carbon contamination; energy level; grain boundaries; localized states; negative temperature coefficient; optical absorption; oxygen; oxygen impurity; photon energy; resonant photothermal bending spectroscopy; solar cells; thermal annealing;

fLanguage

English

Publisher

ieee

Conference_Titel

Photovoltaic Energy Conversion, 2003. Proceedings of 3rd World Conference on

Conference_Location

Osaka, Japan

Print_ISBN

4-9901816-0-3

Type

conf

Filename

1306254