The leakage currents of amorphous silicon thin-film transistors: channel charge emission

Author

Lemmi, Francesco ; Street, Robert A.

Author_Institution

Xerox Palo Alto Res. Center, CA, USA

Volume

47

Issue

12

fYear

2000

fDate

12/1/2000 12:00:00 AM

Firstpage

2399

Lastpage

2403

Abstract

The effects of channel charge emission on the transient leakage currents of amorphous silicon thin-film transistors are described. Up to one hundred devices connected in parallel are used to allow measurement of currents below 1 fA. We develop a procedure to separate the charge-emmission current from the injection and generation currents, based on the dependence on the drain-to-source voltage. The channel emission current is isolated and measured from 10^-3 to 100 s after the TFT is switched off. The current decays approximately as 1/t, and provides information about the density of states in a-Si:H. The channel charge emission also influences the read-out properties of active matrix arrays.

Keywords

amorphous semiconductors; charge injection; elemental semiconductors; hydrogen; leakage currents; semiconductor device measurement; silicon; thin film transistors; 1 fA; 1E-3 to 100 s; Si:H; TFT; a-Si:H; active matrix arrays; amorphous silicon thin-film transistors; channel charge emission; density of states; drain-source voltage; generation currents; injection and generation currents; leakage currents; read-out properties; transient leakage currents; Amorphous silicon; Crystalline materials; Current measurement; Electron traps; Leakage current; Liquid crystal displays; Sensor arrays; Thin film transistors; Voltage; X-ray imaging;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.887028

Filename

887028