Nonstoichiometry and Doping of Zinc Oxide

Contrary to the commonly accepted model, we conclude that the zinc interstitials in Zn1+xO are not ionized. Instead, the electron pair associated with the interstitial zinc is trapped in a metal—metal bond. The increase in conductivity on initial reduction of zinc oxide is associated with impurities such as silicon which are compensated by extra oxygen unless removed by reduction. Zinc oxide powders and thin films were prepared with the dopants B, Al, Ga, In, and Ge. By using high temperatures and highly reducing conditions, conductivities 1000 times higher than previously reported for powders were obtained for some of our powders.