학술논문

Recombination and transport through localized states in hydrogenated amorphous and microcrystalline silicon
Document Type
Article
Author
Source
Journal of Non-Crystalline Solids. May2008, Vol. 354 Issue 19-25, p2067-2078. 12p.
Subject
*ELECTRIC conductivity
*SILICON
*LOW temperatures
*PHOTOLUMINESCENCE
Language
ISSN
0022-3093
Abstract
Abstract: Electrical transport and recombination mechanisms in hydrogenated amorphous silicon, a-Si:H, are determined by localized band-tail states and deep defects. At low temperatures (T <100K) the photoluminescence originates from tunneling recombination between localized band-tail states and the photoconductivity arises from hopping in the band tail. This review describes the present understanding of transport and recombination mechanisms in this low-temperature regime with a focus on two aspects: (i) the kinetics of carrier recombination and the competition between geminate and non-geminate recombination, and (ii) the microscopic identification of recombination paths by magnetic resonance techniques and the proof of excitonic recombination. Inspite of its complex nanocrystalline morphology, hydrogenated microcrystalline silicon, μc-Si:H, behaves in many respects similarly to a-Si:H in that the low-temperature properties are also determined by disorder-induced localized band-tail states. [Copyright &y& Elsevier]