Growth of 4H-SiC Epilayers and Z_1/2 Center Elimination

Abstract:

Thick and low-doped epilayers with a low Z_1/2 center concentration were grown on 8^o off-cut 4H-SiC(0001)Si-face substrate. Two post-growth processes, namely, the C⁺-implantation/annealing process or the thermal oxidation/Ar annealing process, were applied to the thick epilayers. The dependence of the Z_1/2 center concentration and the carrier lifetime on process conditions was investigated. Under proper conditions, both processes could eliminate the Z_1/2 center to a depth of 100 μm or more, and considerably improved the carrier lifetime while maintaining the surface roughness comparable to that of the as-grown sample. The effect of the post-growth processes applied on C-face is also presented.

• Periodical: Materials Science Forum (Volumes 717-720)
• Pages: 81-86
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.717-720.81
• Online since: May 2012
• Authors: Tetsuya Miyazawa, Hidekazu Tsuchida
• Keywords: Carrier Lifetime, Deep Level Transient Microscopy, Epitaxial Growth, Point Defect, Time-Resolved Photoluminescence

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