Study on the Structure of Defects in a-Si:H Films by Positron Annihilation and Micro-Raman Spectroscopy

• Authors: P. Gordo , A. de Lima , M. Ferreira Marques , Zs. Kajcsos
• Languages of publication: EN

Abstracts

EN

Thin films of hydrogenated amorphous silicon deposited on glass and crystalline silicon substrates by rf plasma enhanced chemical vapor deposition at different rf power were studied using slow positron beam and the Raman scattering spectroscopy in order to verify the influence of that deposition parameter on the film defect structure and on the degree of disorder. By positron annihilation spectroscopy, it was found that there are mainly two types of defects in the films: large vacancy clusters or voids and small vacancy type defects. By micro-Raman spectroscopy it was observed that the degree of structural disorder is lower for the film with large vacancy clusters and this finding was related to structural relaxation process. Light soaking induced changes attributed to major atomic rearrangements were also observed.

Keywords

EN

78.66.Jg; 78.70.Bj; 78.30.Ly

Discipline

• 78.70.Bj: Positron annihilation(for positron states, see 71.60.+z in electronic structure of bulk materials; for positronium chemistry, see 82.30.Gg in physical chemistry and chemical physics)
• 78.30.Ly: Disordered solids
• 78.66.Jg: Amorphous semiconductors; glasses

• Journal: Acta Physica Polonica A
• Year: 2008
• Volume: 113
• Issue: 5
• Pages: 1373-1378

Dates

published

2008-05

received

2007-09-03

Contributors

author

P. Gordo

• ICEMS, Department of Physics, University of Coimbra, P-3004-516 Coimbra, Portugal

author

A. de Lima

• ICEMS, Department of Physics, University of Coimbra, P-3004-516 Coimbra, Portugal

author

M. Ferreira Marques

• ICEMS, Department of Physics, University of Coimbra, P-3004-516 Coimbra, Portugal
• Depart. Eng. Quimica, Instituto Superior Engenharia, P-3031-199 Coimbra, Portugal

author

Zs. Kajcsos

• KFKI Res. Inst. for Nucl. and Part. Physics, P.O. Box 49, H-1525 Budapest 114, Hungary

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Identifiers

DOI

10.12693/APhysPolA.113.1373