Effect of Hydrogenation on ZnO Luminescence

Abstract
The effect of hydrogenation on the luminescence property of ZnO crystal was investigated by means of cathodoluminescence (CL). It was found that hydrogen plasma treatment strongly passivates the green emission and enhances the band edge luminescence. The band edge luminescence of ZnO crystals in the as-grown state does not show any significant temperature dependence. However, that of hydrogenated ZnO crystals shows strong temperature dependence and the intensity increases significantly at low temperatures. At 30 K, the number of luminescent photons exceeds several tenths of generated electron-hole pairs.