Realization of highly reproducible ZnO nanowire field effect transistors with n-channel depletion and enhancement modes

Woong-Ki Hong, Department of Materials Science and Engineering, Gwangju Institute of Science and Technology
Dae-Kue Hwang, Department of Materials Science and Engineering, Gwangju Institute of Science and Technology
Il-Kyu Park, Department of Materials Science and Engineering, Gwangju Institute of Science and Technology
Gunho Jo, Department of Materials Science and Engineering, Gwangju Institute of Science and Technology
Sunghoon Song, Department of Materials Science and Engineering, Gwangju Institute of Science and Technology
Seong-Ju Park, Department of Materials Science and Engineering, Gwangju Institute of Science and Technology
Takhee Lee, Department of Materials Science and Engineering, Gwangju Institute of Science and Technology
Bong Joong Kim, Purdue University - Main Campus
E A. Stach, Birck Nanotechnology Center and School of Materials Engineering, Purdue University

Abstract

The authors demonstrate the highly reproducible fabrication of n-channel depletion-mode (D-mode) and enhancement-mode (E-mode) field effect transistors (FETs) created from ZnO nanowires (NWs). ZnO NWs were grown by the vapor transport method on two different types of substrates. It was determined that the FETs created from ZnO NWs grown on an Au-coated sapphire substrate exhibited an n-channel D mode, whereas the FETs of ZnO NWs grown on an Au-catalyst-free ZnO film exhibited an n-channel E mode. This controlled fabrication of the two operation modes of ZnO NW-FETs is important for the wide application of NW-FETs in logic circuits.