| 摘要 |
PURPOSE:To enable emitted light to be guided to a substrate without attenuation and to improve the effective light emission efficiency, by using as a material for a substrate single crystals of aluminium oxide transparent to visible light and interposing a zinc oxide layer for providing a zinc selenide layer having a desirable crystallinity on the substrate. CONSTITUTION:If an Al2O3 substrate 1 has plane orientation of (01-12), a ZnO layer 6 with the (11-20) plane is epitaxially deposited thereon. Further, a ZnSe layer 2 with the (100) plane is epitaxially deposited thereon. An ohmic electrode 5 is directly provided on the n-type ZnSe layer 2. A voltage is applied between an non-ohmic metallic electrode layer 4 and the ohmic electrode 5 such that the non-ohmic metallic electrode layer becomes positive, whereby holes are injected in the N-type ZnSe layer 2. These holes are recoupled with electrons and blue light is emitted. Since both of the single crystal substrate 1 and the ZnO layer 6 are transparent to visible light, the emitted light can be taken out from the rear of the substrate without attenuation, The non-ohmic metallic electrode layer 4 may be made thick enough to completely reflect a component of the emitted light proceeding to the non-ohmic metallic electrode layer 4, whereby an effective light emission efficiency can be improved. |
