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The Electronic Structure, Metastability and Transport Properties of Optimized Amorphous Silicon-Germanium Alloys

Published online by Cambridge University Press:  10 February 2011

Chih-Chiang Chen
Affiliation:
Department of Physics, University of Oregon, Eugene, OR 97403
Yoram Lubianiker
Affiliation:
Department of Physics, University of Oregon, Eugene, OR 97403
J. David Cohen
Affiliation:
Department of Physics, University of Oregon, Eugene, OR 97403
Jeffrey C. Yang
Affiliation:
United Solar Systems Corporation, 1100 West Maple Road, Troy, MI 48084
Subhendu Guha
Affiliation:
United Solar Systems Corporation, 1100 West Maple Road, Troy, MI 48084
Paul Wickboldt
Affiliation:
Division of Applied Sciences, Harvard University, Cambridge, MA 02138
William Paul
Affiliation:
Division of Applied Sciences, Harvard University, Cambridge, MA 02138
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Abstract

We have carried out a comprehensive study of the electronic properties of two series of optimized a-Si1−xGex:H alloys fabricated at United Solar Systems Corporation (“Uni-Solar”) and Harvard University, encompassing the composition range 0.2 ≤ × ≤ 1.0. Both series of samples exhibit deep defect densities that obey quite accurately the spontaneous bond-breaking model proposed by M. Stutzmann which, by considering how the defect formation energy varies with the position of Fermi energy, we have been able to extend to doped samples.

We have also extended our studies to include measurements of ambipolar diffusion lengths and the effects of light-induced degradation, and thus have been able to demonstrate a direct relation between these transport properties and the measured defect levels before and after degradation.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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References

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