Anomalous capture and emission from internal surfaces of semiconductor voids: Nanopores in SiC

Deep level transient spectroscopy in nanoporous, n-type SiC reveals a new type of deep (similar to0.8 eV) trap that can hold more than 100 electrons and that has anomalous capture and emission behavior. Here we quantitatively explain these effects with a new, general formalism that treats both emission and capture in the presence of dynamic energy barriers, resulting from the charging and discharging of states on the internal surfaces of voids, such as pores or nanopipes. The capture kinetics display a logarithmic time dependence over a certain filling range, as has often been observed in connection with dislocation-related trapping.