Table of Contents Author Guidelines Submit a Manuscript
Journal of Nanomaterials
Volume 2015 (2015), Article ID 956101, 10 pages
http://dx.doi.org/10.1155/2015/956101
Research Article

Electrical Properties of Nanoscale ZnS Thin Film Transistor

Semiconductor Engineering, Cheongju University, 298 Daesung-ro Chungwon-ku, Cheongju 360-764, Republic of Korea

Received 3 March 2015; Revised 28 May 2015; Accepted 2 June 2015

Academic Editor: Edward A. Payzant

Copyright © 2015 Teresa Oh. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

To understand the contact mechanism from electrical properties of the ZnS TFTs, ZnS was fabricated on SiOC as a gate insulator on a Si substrate. Ohmic contact without a potential barrier increased the leakage current, but Schottky contact decreased the leakage current because of a Schottky barrier (SB). The ZnS TFTs prepared on SiOC with a Schottky contact improved the stability with respect to the reduction of drain voltages. The structural matching between ZnS and SiOC increased the height of SB such as ZnS annealed at 200°C, which made ZnS become an amorphous structure. ZnS/SiOC films with a low SB increased the capacitance and leakage current. The crystallinity orientation of ZnS localized defect states and the drift current owing to the impurity charge carriers caused the leakage current through low SB near zero voltages. But the increment of diffusion currents in a depletion layer increased the SB and then decreased the leakage current. So the electrical properties of devices were improved by a tunneling effect of diffusion currents.