Development of ohmic contact materials for wide gap p-type 4H-SiC

Author

Tsukimoto, S. ; Nakatsuka, O. ; Moriyama, M. ; Murakami, Masanon

Author_Institution

Dept. of Mater. Sci. & Eng., Kyoto Univ., Japan

fYear

2003

fDate

10-12 Dec. 2003

Firstpage

334

Lastpage

335

Abstract

Conventional TiAl ohmic contacts are annealed at a high temperature which caused extremely rough surface morphology. The objective of this paper is to reduce the annealing temperature of the ohmic contact formation by adding a thin Ni or Ge layer to the TiAl contacts. The microstructure analyses between the SiC and the Ti/Al, Ni/Ti/Al or Ge/Ti/Al contact materials were made using cross sectional high resolution transmission electron microscope. The interfacial microstructure analysis indicated that the reduction of the annealing temperature was obtained due to enhancement of the carbide layer formation by increasing the chemical reactivity between the SiC and the contact materials.

Keywords

aluminium; annealing; crystal microstructure; elemental semiconductors; germanium; interface structure; nickel; ohmic contacts; semiconductor epitaxial layers; silicon compounds; titanium; transmission electron microscopy; wide band gap semiconductors; 10 hr; 200 degC; 400 degC; SiC-Ge-Ti-Al; SiC-Ni-Ti-Al; SiC-Ti-Al; TiAl ohmic contacts; annealing; carbide layer formation; cross sectional high resolution transmission electron microscopy; interfacial microstructure analysis; ohmic contact formation; ohmic contact materials; thin Ge layer; thin Ni layer; wide gap p-type 4H-SiC; Annealing; Chemical analysis; Electrons; Microstructure; Ohmic contacts; Rough surfaces; Silicon carbide; Surface morphology; Surface roughness; Temperature;

fLanguage

English

Publisher

ieee

Conference_Titel

Semiconductor Device Research Symposium, 2003 International

Print_ISBN

0-7803-8139-4

Type

conf

DOI

10.1109/ISDRS.2003.1272120

Filename

1272120