A p-n homojunction ZnO nanorod light-emitting diode formed by As ion implantation

We report stable and repeatable UV and red electroluminescence (EL) from ZnO nanorod (NR) array light-emitting diodes (LEDs), where the $p$ -type ZnO was formed by ${\mathrm{As}}^{+}$ ion implantation into the as-grown ZnO NRs. Both doped and undoped single ZnO NRs were probed using nanomanipulator, where the former ones showed good rectification characteristics, confirming the formation of $p\text{-}n$ homojunctions by ion implantation. Distinct EL emissions in UV and red regions were observed at room temperature under forward bias, where the emission intensity shows amplified spontaneous emission characteristics, suggesting high efficiency of these LEDs.