Light effects of the amorphous indium gallium zinc oxide thin-film transistor

Abstract

The optical and electrical properties of the amorphous indium gallium zinc oxide thin-film transistor (a-IGZO TFT) were studied. When the a-IGZO TFT was illuminated at a wavelength of 660 nm, the off-state drain current slightly increased, while below 550 nm it increased significantly. The a-IGZO TFT was found to be extremely sensitive, with deep-level defects at approximately 2.25 eV near the midgap. After UV light illumination, a slight change occurred on the surface of the a-IGZO films, such as in terms of the oxygen 1s spectra, resistivity, and carrier concentrations. It is believed that these results will provide information regarding the photo-induced behaviors in the a-IGZO films. © 2009 Taylor & Francis Group, LLC.