Studies of Electron Trapping in ZnO Semiconductor

Abstract

It has been recently discovered that electron injection into Phosphorus-, Lithium-, Antimony- or Nitrogen-doped ZnO semiconductor, using electron beam from a Scanning Electron Microscope, as well as a forward bias application to the p-n junction or Schottky barrier, leads to a multiple-fold increase of minority carrier diffusion length and lifetime (1-4). It has also been demonstrated that forward biasing a ZnO-based photovoltaic detector results in a several-fold responsivity enhancement due to a longer minority carrier diffusion length in the detector's p-region as a result of electron injection (5, 6). The observed electron injection effects were attributed to the charging of the meta-stable centers associated with the above-referenced impurities.