Growth and Microstructure of Epitaxial Ti<SUB>3</SUB>SiC<SUB>2</SUB> Contact Layers on SiC
Access this Article
Author(s)
Abstract
Growth and microstructure of ternary Ti<SUB>3</SUB>SiC<SUB>2</SUB> compound layers on 4H-SiC, which play am important role in formation of TiAl-based ohmic contacts to p-type SiC, were investigated in this study. The Ti<SUB>3</SUB>SiC<SUB>2</SUB> layer was fabricated by deposition of Ti/Al contacts (where a slash “/” indicates the deposition sequence) on the 4H-SiC(0001) substrate and subsequent rapid thermal anneal at 1000°C in ultra high vacuum. After annealing, reaction products and microstructure of the Ti<SUB>3</SUB>SiC<SUB>2</SUB> layer were investigated by X ray diffraction analysis and transmission electron microscopy observations in order to understand the growth processes of the Ti<SUB>3</SUB>SiC<SUB>2</SUB> layer and determination of the Ti<SUB>3</SUB>SiC<SUB>2</SUB>/4H-SiC interface structure. The Ti<SUB>3</SUB>SiC<SUB>2</SUB> layers with hexagonal plate shape were observed to grow epitaxially on the SiC(0001) surface by anisotropic lateral growth process. The interface was found to have a hetero-epitaxial orientation relationship of (0001)<SUB>TSC</SUB>||(0001)<SUB>S</SUB> and [0\\bar110]<SUB>TSC</SUB>||[0\\bar110]<SUB>S</SUB> where TSC and S represent Ti<SUB>3</SUB>SiC<SUB>2</SUB> and 4H-SiC, respectively, and have well-defined ledge-terrace structures with low density of misfit dislocations due to an extremely low lattice mismatch of 0.4% between Ti<SUB>3</SUB>SiC<SUB>2</SUB> and 4H-SiC.
Journal
-
- MATERIALS TRANSACTIONS
-
MATERIALS TRANSACTIONS 50(5), 1071-1075, 2009
The Japan Institute of Metals and Materials