Table of Contents
ISRN Electronics
Volume 2013, Article ID 271658, 5 pages
http://dx.doi.org/10.1155/2013/271658
Research Article

Influence of Carbon Layer on the Properties of Ni-Based Ohmic Contact to n-Type 4H-SiC

1V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, Pr. Nauky 45, 03028 Kyiv, Ukraine
2Institute of Physics, PAS of Poland, Al. Lotnikow 32/46, 02-668 Warsaw, Poland
3Institute of Electron Technology, Al. Lotnikow 32/46, 02-668 Warsaw, Poland

Received 27 November 2012; Accepted 5 February 2013

Academic Editors: C. W. Chiou and L.-F. Mao

Copyright © 2013 A. Kuchuk et al. 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

Nickel-based contacts with additional interfacial layer of carbon, deposited on n-type 4H-SiC, were annealed at temperatures ranging from 600 to 1000°C and the evolution of the electrical and structural properties were analyzed by I-V measurements, SIMS, TEM, and Raman spectroscopy. Ohmic contact is formed after annealing at 800°C and minimal specific contact resistance of about  Ω cm2 has been achieved after annealing at 1000°C. The interfacial carbon is amorphous in as-deposited state and rapidly diffuses and dissolves in nickel forming graphitized carbon. This process activates interfacial reaction between Ni and SiC at lower temperature than usual and causes the formation of ohmic contact at relatively low temperature. However, our results show that the specific contact resistance as well as interface quality of contacts was not improved, if additional layer of carbon is placed between Ni and SiC.