Optical Studies of Nonequilibrium Carrier Dynamics in Highly Excited 4H-SiC Epitaxial Layers


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We applied picosecond four-wave mixing technique to investigate carrier diffusion and recombination in n-type 4H-SiC epilayers. The dependence of bipolar diffusion coefficient D on photocarrier density was measured in range from ~ 1017 to ~ 1020 cm-3. We determined a decrease of D value from 3.4 to 2.2 cm2/s with increase of the photoexcitation level in range from ~ 1017 to ~ 1019 cm-3, and found its increase up to 3.8 cm2/s at carrier density above 1020 cm-3. Auger recombination governed decrease of carrier lifetime from 11 ns at ~ 1017 cm-3 to 1.8 ns at ~ 1020 cm- 3 has also been observed.



Materials Science Forum (Volumes 483-485)

Edited by:

Dr. Roberta Nipoti, Antonella Poggi and Andrea Scorzoni




K. Neimontas et al., "Optical Studies of Nonequilibrium Carrier Dynamics in Highly Excited 4H-SiC Epitaxial Layers", Materials Science Forum, Vols. 483-485, pp. 413-416, 2005

Online since:

May 2005




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DOI: https://doi.org/10.4028/www.scientific.net/msf.338-342.671

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