Optical Properties of ZnO-Alloyed Nanocrystalline Films

[摘要] ZnO is emerging as one of the materials of choice for UV applications. It has a deep excitonic energy level and a direct bandgap of ~3.4 eV. Alloying ZnO with certain atomic constituents adds new optical and electronic functionalities to ZnO. This paper presents research onMgxZn1−xOandZnS1−xOxnanocrystalline flexible films, which enable tunable optical properties in the deep-UV and in the visible range. The ZnO andMg0.3Zn0.7Ofilms were found to have bandgaps at 3.35 and 4.02 eV, respectively. The photoluminescence of theMg0.3Zn0.7Oexhibited a bandedge emission at 3.95 eV, and at lower energy 3.38 eV due to the limited solubility inherent to these alloys.ZnS0.76O0.24andZnS0.16O0.84were found to have bandgaps at 3.21 and 2.65 eV, respectively. The effect of nitrogen doping onZnS0.16O0.84is discussed in terms of the highly lattice mismatched nature of these alloys and the resulting valence-band modification.

[学科分类] 材料工程