Temperature stability of cobalt Schottky contacts on n- and p-type 6H silicon carbide

doi:10.1016/0169-4332(93)90186-F

Applied Surface Science

Volume 73, 2 November 1993, Pages 316-321

https://doi.org/10.1016/0169-4332(93)90186-F Get rights and content

Abstract

Rectifying Schottky contacts have been manufactured on n- and p-type 6H silicon carbide using e-beam evaporation of cobalt. Heat treatments in the 300 to 1100°C temperature range have been made to study the feasibility of high temperature contacts in this material system. Rutherford backscattering spectrometry and X-ray diffraction have revealed the formation of different cobalt silicides (Co₂Si, CoSi, and CoSi₂) at higher temperatures than for the Co/Si system. No evidence of silicidation was found below 600°C and SEM micrographs revealed carbon agglomerates at the surface after silicidation. Electrical properties have been examined using I–V and C–V measurements, and the barrier heights of cobalt and Co₂Si were evaluated. The contacts displayed excellent forward I–V characteristics with good linearity over 3–6 decades and were rectifying even after heat treatments at 800°C.

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Citation Excerpt :
SiC Schottky rectifiers are also of considerable relevance for research due to the Schottky diode inhomogeneity, and they also often suffer from excess reverse leakage current and excess forward current at low voltages. Many researchers have studied the properties of SiC Schottky rectifiers on 3C–SiC [7], then on 6H–SiC [1,8–11], and more recently on 4H–SiC [12,13]. However, The Schottky diode inhomogeneity is probably due to the materials and interface quality, with various defects such as carrots, growth pits, and micropipes [1].
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Temperature stability of cobalt Schottky contacts on n- and p-type 6H silicon carbide

Abstract

Nucl. Instr. Meth.

Proc. IEEE

Semicond. Sci. Technol.

J. Appl. Phys.

J. Appl. Phys.