Ohmic contact formation between metal and AlGaN/GaN heterostructure via graphene insertion
Abstract
A simple method for the creation of Ohmic contact to 2D electron gas in AlGaN/GaN high electron-mobility transistors using Cr/graphene layer is demonstrated. A weak temperature dependence of this Ohmic contact observed in the range 77 to 300 K precludes thermionic emission or trap-assisted hopping as possible carrier-transport mechanisms. It is suggested that the Cr/graphene combination acts akin to a doped n-type semiconductor in contact with AlGaN/GaN heterostructure, and promotes carrier transport along percolating Al-lean paths through the AlGaN layer. This use of graphene offers a simple method for making Ohmic contacts to AlGaN/GaN heterostructures, circumventing complex additional processing steps involving high temperatures. These results could have important implications for the fabrication and manufacturing of AlGaN/GaN-based microelectronic and optoelectronic devices/sensors of the future.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 15, 2013
- Source ID
- 10.1063/1.4801940
Entities
People
- Digbijoy N. Nath
- K. M. Reddy
- Nitin P Padture
- Pil Sung Park
- Siddharth Rajan
- Zhichao Yang
Organizations
- Brown University
- National Science Foundation
- Office of Naval Research
- Ohio State University