Enhanced Annealing of the Main Lifetime Limiting Defect in Thick 4H-SiC Layers
We have studied annealing of the main lifetime limiting defect Z1/2 in thick 4H-SiC epilayers by the application of carbon-implantation/annealing method. Examination of different implantation doses and annealing temperatures showed that finding the optimum conditions is crucial for obtaining carrier trap concentration below 1011 cm-3 in the whole 100 μm epilayer. The carrier lifetime increased from under 200 ns to over 1 μs at room temperature in the samples prepared by optimized carbon-implantation/annealing technique. Fabrication of pin diodes from the improved thick 4H-SiC epilayers confirmed the enhanced conductivity modulation and suitability of this technique for high-voltage bipolar SiC devices.
Akira Suzuki, Hajime Okumura, Tsunenobu Kimoto, Takashi Fuyuki, Kenji Fukuda and Shin-ichi Nishizawa
L. Storasta et al., "Enhanced Annealing of the Main Lifetime Limiting Defect in Thick 4H-SiC Layers", Materials Science Forum, Vols. 600-603, pp. 477-480, 2009