Dependence of Photosensitive Effect on the Defects Created by DC Stress for LTPS TFTs

Author

Tai, Ya-Hsiang ; Kuo, Yan-Fu ; Lee, Yun-Hsiang

Author_Institution

Dept. of Photonics & Display Inst., Nat. Chiao Tung Univ., Hsinchu

Volume

29

Issue

12

fYear

2008

Firstpage

1322

Lastpage

1324

Abstract

In this letter, the photosensitive effect of n-type low-temperature polycrystalline silicon (LTPS) thin-film transistors (TFTs) after DC stress was investigated. It was discovered that the photo-generated carrier behaviors under optical illumination are related to defect types created by different stress conditions of hot-carrier effect and self-heating effect. These two types of defect creation result in the different photosensitivity behaviors of LTPS TFT. A model considering the relation between photosensitivity and defect is proposed to explain the anomalous illumination behaviors after device degradation.

Keywords

hot carriers; photoconductivity; phototransistors; silicon; stress effects; thin film transistors; DC stress; LTPS TFT; Si; defect creation; hot-carrier effect; n-type low-temperature polycrystalline silicon thin-film transistors; optical illumination; photogenerated carriers; photosensitive effect; self-heating effect; Degradation; Glass; Hot carrier effects; Lighting; Optical films; Photonics; Silicon; Stress; Thin film transistors; Voltage; DC stress; leakage current; photosensitivity; poly-Si thin-film transistor (TFT);

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2008.2006414

Filename

4671161