How to achieve ultra high photoconductive gain for transparent oxide semiconductor image sensors

Author

Sungsik Lee ; Sanghun Jeon ; Robertson, John ; Nathan, Arokia

Author_Institution

London Center for Nanotechnol., Univ. Coll. London, London, UK

fYear

2012

fDate

10-13 Dec. 2012

Abstract

We present quantitative analysis of the ultra-high photoconductivity in amorphous oxide semiconductor (AOS) thin film transistors (TFTs), taking into account the sub-gap optical absorption in oxygen deficiency defects. We analyze the basis of photoconductivity in AOSs, explained in terms of the extended electron lifetime due to retarded recombination as a result of hole localization. Also, photoconductive gain in AOS photo-TFTs can be maximized by reducing the transit time associated with short channel lengths, making device scaling favourable for high sensitivity operation.

Keywords

amorphous semiconductors; carrier lifetime; image sensors; light absorption; photoconductivity; photodetectors; thin film transistors; AOS; TFT; amorphous oxide semiconductor; electron lifetime; hole localization; optical absorption; oxygen deficiency defect; photoconductive gain; photoconductivity; retarded recombination; thin film transistors; transparent oxide semiconductor image sensor; Absorption; Charge carrier processes; Density measurement; Logic gates; Spontaneous emission; Thin film transistors; Threshold voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Electron Devices Meeting (IEDM), 2012 IEEE International

Conference_Location

San Francisco, CA

ISSN

0163-1918

Print_ISBN

978-1-4673-4872-0

Electronic_ISBN

0163-1918

Type

conf

DOI

10.1109/IEDM.2012.6479094

Filename

6479094