Current-driven hydrogen incorporation in zinc oxide

The effect of electrical current on the hydrogen incorporation into single crystalline ZnO was investigated. The current-voltage characteristics of single crystalline ZnO were measured as a function of the electrical conductivity of ZnO. The electrical current of ZnO was significantly increased at the second sweep of voltages when the electrical conductivity of ZnO was higher than 0.32 S/cm. A depth profiling analysis of ZnO by dynamic secondary ion mass spectrometry indicated that the hydrogen atoms were incorporated to form hydrogen-related donors, such as a substitutional hydrogen (H-O) and an interstitial hydrogen (H-i), which resulted in an increase in the donor concentration of ZnO. (C) 2007 American Institute of Physics.