Schottky diode with silver layer contacting the ZnO and MgxZn1−xO films

US7400030B2 · kind B2 · utility

Assignee

• Rutgers, the State University of New Jersey · US

Inventors

• Yicheng Lu · East Brunswick Township, US
• Haifeng Sheng · Rexford, US
• Sriram Muthukumar · Chandler, US
• Nuri Emanetoglu · Woodbury, US
• Jian Zhong · Cenxi, CN
• Shaohua Liang · Somerville, US

Key dates

• Filing date: Jan 25, 2005
• Grant date: Jul 15, 2008
• Expiry date: Aug 2, 2025

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E10/50

Abstract

In the present invention, there is provided semiconductor devices such as a Schottky UV photodetector fabricated on n-type ZnO and MgxZn1-xO epitaxial films. The ZnO and MgxZn1-xO films are grown on R-plane sapphire substrates and the Schottky diodes are fabricated on the ZnO and MgxZn1-xO films using silver and aluminum as Schottky and ohmic contact metals, respectively. The Schottky diodes have circular patterns, where the inner circle is the Schottky contact, and the outside ring is the ohmic contact. Ag Schottky contact patterns are fabricated using standard liftoff techniques, while the Al ohmic contact patterns are formed using wet chemical etching. These detectors show low frequency photoresponsivity, high speed photoresponse, lower leakage current and low noise performance as compared to their photoconductive counterparts. This invention is also applicable to optical modulators, Metal Semiconductor Field Effect Transistors (MESFETs) and more.