| 摘要 |
<p>An ultrafine grain fluorescent body comprises an ultrafine grain luminescent material containing an activator and having a surface carrying thereon a layer which is formed from a different material from the luminescent material, or which has different properties from those of the luminescent material. The layer forms a heterojunction or p-n junction defining a luminescent mechanism in an interface between the luminescent material and the layer. The heterojunction is formed if the layer is a film of oxide, nitride or any other different substance formed on the surface of the luminescent material, e.g. ZnS, having a grain size of several hundred to several thousand angstroms. Alternatively, the p-n junction is formed if the luminescent material is a p-type (or n-type) semiconductor, and if the layer is a film of an n-type (or p-type) semiconductor formed on the surface thereof. The fluorescent body of this invention is useful for making an electroluminescent (EL) element having a high luminance, a high luminescent efficiency and a high resolution, and capable of being driven by a low voltage.</p> |
