Abstract
Zinc oxide (ZnO) is an interesting and promising semiconductor material for many potential applications, e.g. in opto-electronics and for sensor devices. However, its p-type doping represents a challenging problem, and the physical reasons of its mostly n-type conductivity are not perfectly clear at present.
Efforts to achieve p-type conductivity by ion implantation are reviewed, and ways to achieve p-type ZnO nanorods and thin films through various growth conditions are summarized.