Quantification of the bond-angle dispersion by Raman spectroscopy and the strain energy of amorphous silicon

A thorough critical analysis of the theoretical relationships between the bond-angle dispersion in a-Si, Δθ, and the width of the transverse optical Raman peak, Γ, is presented. It is shown that the discrepancies between them are drastically reduced when unified definitions for Δθ and Γ are used. Th...

Descripción completa

Detalles Bibliográficos
Autores: Roura Grabulosa, Pere, Farjas Silva, Jordi, Roca i Cabarrocas, Pere
Tipo de recurso: artículo
Fecha de publicación:2008
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10256/3222
Acceso en línea:http://hdl.handle.net/10256/3222
Access Level:acceso abierto
Palabra clave:Cristal·lització
Espectroscòpia Raman
Moviment ondulatori, Teoria del
Reaccions d'anihilació
Semiconductors amorfs
Silici
Amorphous semiconductors
Annihilation reactions
Crystallization
Raman spectroscopy
Silicon
Descripción
Sumario:A thorough critical analysis of the theoretical relationships between the bond-angle dispersion in a-Si, Δθ, and the width of the transverse optical Raman peak, Γ, is presented. It is shown that the discrepancies between them are drastically reduced when unified definitions for Δθ and Γ are used. This reduced dispersion in the predicted values of Δθ together with the broad agreement with the scarce direct determinations of Δθ is then used to analyze the strain energy in partially relaxed pure a-Si. It is concluded that defect annihilation does not contribute appreciably to the reduction of the a-Si energy during structural relaxation. In contrast, it can account for half of the crystallization energy, which can be as low as 7 kJ/mol in defect-free a-Si