Characterization of electronic properties of different SiC polytypes by all-optical means
2009 (English)In: Materials Science Forum, Vols. 600-603, 2009, Vol. 600-603, 509-512 p.Conference paper (Refereed)
We applied a picosecond transient grating technique for studies of nonequilibrium carrier dynamics in differently grown or doped SiC polytypes. Optical carrier injection in 4H-SiC at two different wavelengths (266 and 355 nm) allowed us to vary the depth of the photoexcited region and determine photoelectric parameters of high density (from ~1016 to ~1019 cm-3) carrier plasma in the temperature range 10-300 K. A strong decrease of carrier lifetime with increasing nonequlibrium carrier density was found in 4H-SiC samples at 300 K and fitted by bimolecular recombination with coefficient B = 3 � 10-11 cm3 s-1. In 3C-SiC epilayers, the opposite tendency was observed over a wide temperature range and attributed to recharging of defect states.
Place, publisher, year, edition, pages
2009. Vol. 600-603, 509-512 p.
Carrier lifetime; Carrier scattering; Diffusion coefficient; Mobility
IdentifiersURN: urn:nbn:se:liu:diva-18775DOI: 10.4028/3-908453-11-9.509OAI: oai:DiVA.org:liu-18775DiVA: diva2:221775