Remarks on the nature of Urbach absorption tail in glassy semiconductors

Author

Tsiulyanu, D.I. ; Marian, S.I.

Author_Institution

Dept. of Phys., Tech. Univ., Kishinau, Moldova

fYear

1995

fDate

11-14 Oct 1995

Firstpage

399

Lastpage

402

Abstract

Exponential absorption edge of chalcogenide glassy alloys with sulfur content in the region of the topological transition is studied. It is shown that the slope of the tail (1/Δ) depends on the mean coordination number (r¯), the mean volume occupied by an atom (V) and the stoichiometry (Ω) of the materials, i. s. Δ=f(r¯, V, Ω). Analysis of the experimental results for alloys As-S-Ge as well as for other amorphous materials, including the elemental ones indicates that the topological disorder controlled by r¯, Ω and V is the main reason in formation of the exponential absorption tail

Keywords

arsenic compounds; chalcogenide glasses; light absorption; As-S-Ge; Urbach absorption tail; amorphous materials; atomic volume; chalcogenide alloys; coordination number; electronic transition; elements; exponential absorption edge; glassy semiconductors; stoichiometry; topological disorder; Absorption; Amorphous materials; Fluctuations; Materials reliability; Optical materials; Physics; Predictive models; Probability distribution; Reliability theory; Tail;

fLanguage

English

Publisher

ieee

Conference_Titel

Semiconductor Conference, 1995. CAS'95 Proceedings., 1995 International

Conference_Location

Sinaia

Print_ISBN

0-7803-2647-4

Type

conf

DOI

10.1109/SMICND.1995.495045

Filename

495045