abstract |
Zinc oxide (ZnO) inherently exhibits n-type behavior due to naturally-occurring oxygen vacancies and zinc interstitials. Many other metal oxide systems have been found to exhibit similar semiconductor characteristics as zinc oxide, i.e. inherently n-type, including other metal oxide semiconductors such as GaO, MgO, CuO, etc. or ternary alloys with zinc oxide such as MgZnO, CdZnO, GaZnO, etc. The method described herein creates stable p-type ZnO or other metal oxide semiconductor materials, by using an oxygen scavenger material, e.g. calcium or tungsten, that is introduced during the formation of the material which preferentially scavenges oxygen resulting in an abundance of zinc vacancies, which act as holes, and induces stable p-type behavior without alloying or being incorporated into the semiconductor material itself. Three deposition techniques to deposit this stable form of p-type material and p+ type material are described. |