Evaluation of Auger Recombination Rate in 4H-SiC

The carrier lifetime in 4H-SiC material is studied using a time-resolved free carrier absorption technique. The Auger recombination coefficient {gamma}{sub 3} = (7{+-}1) x 10{sup -31} cm{sup 6}s{sup -1} is derived from the kinetics of a highly excited electron-hole plasma in low doped 4H-SiC epitaxial layers. In addition, the recombination rate of e-e-h Auger process has been evaluated separately in heavily doped n-type 4H-SiC, yielding {gamma}{sub 3}{sup eeh} = (5{+-}1) x 10{sup -31} cm{sup 6}s{sup -1} at room temperature. The e-e-h type band-to-band Auger recombination is shown to be the dominant mechanism in 4H-SiC at high carrier concentrations. (orig.) 6 refs.