Minority carrier diffusion length measurements in 6H-SiC J. Appl. Phys. 97, 053703 (2005); 10.1063/1.1853501Influence of crystal quality on the electronic properties of n-type 3C-SiC grown by low temperature low pressure chemical vapor deposition
The temperature dependence of carrier recombination lifetime for n-and p-type Si wafers is measured by the photoconductivity decay method in a temperature range between room temperature and about 90 K. The carrier lifetime of as-polished wafers has very weak temperature dependence, while the carrier lifetime decreases steeply with decreasing temperature f or oxidized wafers. For all samples, a slow component appears in the photoconductivity decay curves after an initial fast decay at temperatures below 150 K. From a numerical simulation, we conclude that the decrease in the carrier lifetime with decreasing temperature is due to recombination through shallow recombination centers with an energy level within 0.15 eV from the bandedge, and that the slow component is due to minority carrier traps with a small majority carrier capture cross section.
N-type 3C-SiC layers grown on p-type (001) Si substrates were characterized by the conventional photoconductivity decay method. A N2 laser (337 nm wavelength) was used as the excitation source. A very slow component with a time constant larger than 1 ms was observed in the photoconductivity decay curves. A numerical simulation considering a trap with a very small capture cross section for electrons (<1×10−21 cm2) was able to reproduce main qualitative features of the experimental results. From comparison of the experimental decay curves with the theoretical ones, the following conclusions were drawn about the trap in 3C-SiC. (1) The trap level Et is close to the conduction band edge Ec(Ec−Et=0.1–0.15 eV). (2) The concentration is considered to decrease with increasing donor concentration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.