Thermal Oxidation Of Metallic Zinc Film Preparation Of Zinc Oxide-based Material Ultraviolet Light-emitting Properties

Zinc oxide is a II-VI wide band-gap (3.3eV) compound semiconductor with wurtzite crystal structure. Due to the large exciton binding energy of 60meV, which ensures the high efficient excitonic emission at room temperature, it is regarded as one of the most promising materials for fabricating efficient ultraviolet (UV) and blue light emitting devices. ZnO has the highest conductivity in all of the semiconductor materials, at the same time it is very chemically and thermodynamically stable as other oxides. Since the first observation of the stimulated ultraviolet emission at room temperature, ZnO has become another hotspot in the region of UV light emitting researching.In this dissertation, nanometer ZnO thin films on Si (100) substrates were prepared by using thermal evaporation technique following by two-step annealing process: High quality ZnO thin films and MgxZn1-xO alloy films have been grown on Si (100) substrates with MgO buffer layers by using thermal evaporation technique following by two-step annealing process. X-ray diffraction (XRD), reflection spectroscopy and photoluminescence spectroscopy were employed to study the optical properties of ZnO films and MgxZn1-xO alloy films. The relationship between the optical properties and the crystallinity was discussed.The experimental results show that the quality of ZnO films prepared by electron beam evaporation can be greatly improved by means of two-step annealing of metallic Zn films in oxygen ambient, and it is feasible to fabricate high quality MgxZn1-xO alloy films with MgO buffer layers by using thermal evaporation technique following by two-step annealing process. This method gives a new path to prepare MgxZn1-xO alloy films.