| Summary: | 碩士 === 國立虎尾科技大學 === 光電與材料科技研究所 === 103 === In this study, by using RF magnetron co-sputtering system with ZnO and AlN target, respectively, deposited un-doped ZnO thin films and ZnO doped Al thin film, and using AlN-ZnO sputtering thin film to be a barrier layer, un-doped ZnO thin films to be active layers to produce double heterostructures and multi-quantum well structure, second annealing under vacuum ambient activates the dopant atoms in the films. After annealing under vacuum ambient, We measured our samples about the electrical properties, optical properties of thin films with photoluminescence light-emitting properties and the composition with the film crystal structure and analysis the thin film carrier mechanism and conduction type. Result of the study, after annealing under vacuum ambient, observed the average transmittance were over 80% about the double heterostructure (AlN-ZnO/ZnO/AlN-ZnO) and multi quantum well structure, due to the interface of AlN-ZnO / ZnO diffusion of aluminum atoms substituted the zinc atom, to support more electronic carrier, therefore, comparing with the un-doped ZnO, the electron carrier concentration has improved significantly of the double heterostructure and Multi-Quantum Well structure. Next, the barrier layer(AlN-ZnO) and un-doped well layer(ZnO) repeat stacked to form a multi-quantum well structure, observed the multilayer structure can provide more potential energy well, so the more electrons and holes are confined to potential energy wells layer, leading to the peak intensity increases of the radiative recombination radiation with increasing the number of quantum wells and has significantly enhanced the phenomenon, when quantum well layer increased to thirty period, due to quantum well stacked a lots, the number of electron and hole composite reach a saturation, due to the structure with multilayer stack makes a lot of accumulated stress, caused by the crystallization characteristics worse, Which led to a multi-quantum well structure
luminous intensity rise less obvious, even the multiple-quantum well’s period were more than 25-period, the luminous intensity will gradually shows the trend of a level of saturation trend.
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