Metastable defects generated by hole injection under the constant current condition are studied above room temperature. Defect saturation behavior is observed after sufficient period of current soaking, which is faster at higher temperatures. The saturated defect density ij obtained from the space charge limited current. We propose a simple model for the defect kinetics in which hole induced defect creation and annihilation as well as thermal annealing processes are considered. This model includes dispersive hydrogen diffusion and fits well with the present experimental data. Copyright (C) 1996 Elsevier Science Ltd