Analysis of carrier lifetimes in n-type 4H-SiC by rate equations

The authors constructed a model for carrier recombination process via the Z(1/2) center in n-type 4H-SiC by using rate equations which adopted realistic capture cross sections. The high-injection carrier lifetime is about ten times longer than low-injection carrier lifetime, which originates from the fact that the (0) state of the Z(1/2) center and the (-) state are dominated the under the high-injection condition and low-injection condition, respectively. The results obtained from the present model well explain the relationship between the lifetime and the carbon vacancy density experimentally obtained when the carbon vacancy density is higher than 1 - 3 x 10(11) cm(-3). (C) 2019 The Japan Society of Applied Physics