Electron transport in degenerate Mn-doped ZnO nanowires

The authors have performed variable-temperature electrical measurements on individual single-crystalline, Mn-doped ZnO nanowires. Using a back-gated field-effect transistor structure fabricated with electron-beam lithography, they have established that nanowires exhibit n-type conduction. At a temperature of 225K, the field-effect mobility and free electron concentration are ≈35cm2V−1s−1 and ≈3.6×1017cm−3, respectively. Carrier concentration varies weakly with temperature down to 12K, signifying that the material is degenerate. Mobility decreases with decreasing temperature down to 12K, in a manner consistent with ionized impurity scattering in a degenerate semiconductor.