Recovery from ultraviolet-induced threshold voltage shift in indium gallium zinc oxide thin film transistors by positive gate bias
Li, X. D.
Wong, J. I.
Leong, K. C.
Date of Issue2013
School of Electrical and Electronic Engineering
The effect of short-duration ultraviolet (UV) exposure on the threshold voltage (Vth) of amorphous indium gallium zinc oxide thin film transistors (TFTs) and its recovery characteristics were investigated. The Vth exhibited a significant negative shift after UV exposure. The Vth instability caused by UV illumination is attributed to the positive charge trapping in the dielectric layer and/or at the channel/dielectric interface. The illuminated devices showed a slow recovery in threshold voltage without external bias. However, an instant recovery can be achieved by the application of positive gate pulses, which is due to the elimination of the positive trapped charges as a result of the presence of a large amount of field-induced electrons in the interface region.
DRNTU::Engineering::Materials::Microelectronics and semiconductor materials::Thin films
Applied physics letters
© 2013 AIP Publishing LLC. This paper was published in Applied Physics Letters and is made available as an electronic reprint (preprint) with permission of AIP Publishing LLC. The paper can be found at the following official DOI: [http://dx.doi.org/10.1063/1.4830368]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.