GaP/ZnO nanowires with a radial pn heterojunction

Core-shell p-GaP/n-ZnO nanowires (NWs) were prepared and studied. There was a radial pn heterojunction between the core and the shell. The NWs were processed in a two-step technique in which the GaP core and ZnO shell of an individual NW were separately provided with ohmic contacts. This required using two different types of ohmic metallization alloyed at different temperature, which also differed from the growth temperature. The contacts were processed with electron beam lithography and lift-off. The NWs were electrically characterized: the I-V characteristics measurement confirmed that a pn heterojunction formed between p-GaP core and n-ZnO shell of the NWs.