Edge quantum yield in n -channel metal-oxide-semiconductor field-effect transistor

The quantum yield of impact ionization is performed on an n-channel metal-oxide-semiconductor field-effect transistor (n-MOSFET) by a carrier separation measurement. When the n-MOSFET is biased in accumulation, the carrier separation measurement demonstrates that the gate current mainly originates from the electrons injected into the underlying drain/source overlap regions. The measured substrate current is due to excess holes originating from the impact ionization of the injected electrons in the overlap regions. Therefore, the quantum yield in the overlap regions can be determined by the ratio of the substrate current to the gate current. It is well matched with the theoretical calculation of quantum yield.