| ZnO is important II-VI direct band gap semiconductor material, which has band gap of 3.37 eV at room temperature, and the binding energy of exciton as high as 60 meV. Since the realization of stimulated emission of ZnO films at room temperature by optical pumping in 1996, researches on ZnO and its related materials have become one of the most promising and attractive aspects in the optoelectronic field. However, development of higher-efficiency homojuction devices has been limited by the lack of reliable p-type ZnO. According to the present research hotspots and difficulties on ZnO, we pay more attention to the p-type ZnO in this thesis. The conversion process from n-type to p-type was researched. Additionally, the stability of p-type ZnO is discussed. The details are as follows:1. Thin films of p-type ZnO: N have been obtained by thermally oxiding zinc oxynitride films prepared by plasma enhanced chemical vapor deposition (PECVD). A conductivity-type transition from n-type to p-type was observed, which was systematically researched via the structural and compositional analyses. First, nitrogen was incorporated into ZnO films during the growth process to occupy oxygen positions, also partly compensated some donors induced from nonstoichiometric (ZnO1-x) composition. Secondly, the number of activated nitrogen gradually increased in an oxidizing atmosphere and exceeded those donor states to realize an effective compensation, yielding p-type conductivity during thermal oxidation course.2. Electrical properties of p-type ZnO: N films grown by thermal activation of nitrogen dopant were investigated via the temperature-dependent Hall-effect. The Hall mobility increases with decreasing temperature. Varied scattering mechanisms have been analyzed including lattice vibration scattering, ionized...
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