Summary: | 碩士 === 國立屏東科技大學 === 機械工程系 === 93 === ZnS doping Cu or Br powder is a kind of fluorophor emiting blue or green light with the activation of high electric field. The ZnS: Cu series high electric field luminescence has long been studied. However, it is difficult to get the pure blue light. This experiment use ZnS powder with 4N purity as the host material, the luminescence center is formed by adding Cu ion and Br ion. The source of Cu and Br is copper acetate and ammonium bromide. In order to prevent sulphur vacancies, powder is sintered in a close and vacuum tube at 900℃ for 1 hr, not in an open tube with sulfur source(usually takes more then 5 hrs). It can be found out by the experiment result that the main factors influencing powder electroluminescence is as follows: 1. the size and shape of the grain. 2. The distribution of Cu concentration. Among all the making conditions, the one have the biggest influence is sintering method, cooling method and chemical etching. It is proven by the chemical etching result that Cu dissolves in the ZnS and form the core part of the grain but don’t distribute evenly; making appropriate chemical etching can get the highest brightness. Examination of the powder is based on the results of XRD, SEM, EPMA.
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