Optically Detected Temperature Dependences of Carrier Lifetime and Diffusion Coefficient in 4H- and 3C-SiC
Free carrier dynamics has been studied in 4H- and 3C-SiC in a wide temperature range using time-resolved photoluminescence, free carrier absorption, and light induced transient grating techniques. Considerably high carrier lifetime was observed in 3C-SiC epitaxial layers grown on 4H-SiC substrates using hot-wall CVD with respect to previously reported values for 3C-SiC grown either on Si or on 6H-SiC substrates. The temperature dependences of carrier lifetime and diffusion coefficient for 4H- and 3C-SiC were compared. Shorter photoluminescence decay time with respect to free carrier absorption decay time was observed in the same 4H-SiC sample, while these techniques revealed similar trends in the carrier lifetime temperature dependencies. However, the latter dependences for hot-wall CVD-grown 3C layers were found different if measured by time resolved photoluminescence and free carrier absorption techniques.
Edouard V. Monakhov, Tamás Hornos and Bengt. G. Svensson
J. ul Hassan et al., "Optically Detected Temperature Dependences of Carrier Lifetime and Diffusion Coefficient in 4H- and 3C-SiC", Materials Science Forum, Vols. 679-680, pp. 205-208, 2011