An improved analysis for band edge optical absorption spectra in hydrogenated amorphous silicon from optical and photoconductivity measurements

Autor:	C. R. Wronski, R. W. Collins, N. Hata, Lihong Jiao, Ing-Shin Chen
Rok vydání:	1998
Předmět:	Amorphous silicon Materials science Physics and Astronomy (miscellaneous) Silicon business.industry Photoconductivity chemistry.chemical_element Photon energy Molecular physics Spectral line chemistry.chemical_compound Dipole Semiconductor chemistry Optoelectronics business Spectroscopy
Zdroj:	Applied Physics Letters. 72:1057-1059
ISSN:	1077-3118 0003-6951
DOI:	10.1063/1.120963
Popis:	The uncertainties inherent in the normalization of subgap photoconductivity spectra to the optical absorption spectra α(hv) in a-Si:H based films have been addressed. An analysis is presented which is based on optical transitions of constant dipole matrix element between parabolic distributions of extended states and exponential distributions of localized tail states. This analysis has been used to normalize the two sets of results accurately, as verified by photothermal deflection spectroscopy measurements, and is shown to be useful in the commonly encountered cases, in which the two spectra do not overlap over an extended region. Improved quantitative fits of α(hv), for photon energy from ∼1.5 to 2.4 eV, obtained on different a-Si:H based films indicate that the localized exponential band tail regions extend ∼60–70 meV above the optical gap.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::eae4442a9de11ddad9bd8e8a98ce3244 https://doi.org/10.1063/1.120963 Zobrazit plný text záznamu