ABSTRACT
This chapter describes the preparation of ZnBeO and ZnBeMgO alloys and various applications of ZnO-based optoelectronic devices. In order to develop zinc oxide (ZnO)-based ultraviolet (UV) optoelectronic devices, it is necessary to find suitable materials with the same crystal structure as ZnO but with wider bandgap with respect to ZnO. The structural and optical properties of these alloys have also been investigated experimentally and theoretically. The phase segregation is resulting from the different crystal structure, the large lattice mismatch between the components of the crystalline alloy, and the lattice mismatch between the deposited film and the substrate. In order to obtain high-quality crystalline ZnO-based films with bandgap modulation to the deeper ultraviolet region, it is required to incorporate appropriate amount of beryllium into ZnMgO to form quaternary alloys. Band structure is a fundamental issue for material study, especially for band engineering study.
