| 摘要 |
PURPOSE:To obtain a blue light emitting element excellent in luminous efficiency by a method wherein an n-type ZnSe luminous layer is formed on a p-type GaAs substrate crystal sandwiching a hole current injection layer of p-type whose band gap is larger than that of the substrate crystal in between them. CONSTITUTION:A current injection layer 2 of p-type Al0.7Ga0.3As, an i-type ZnSe layer 3, an n-type ZnSe luminous layer 4, and electrodes 5 and 6 are provided onto a p-type GaAs substrate 1. When voltage is impressed on the electrodes 5 and 6, holes are injected into the luminous layer 4 from the current injection layer 2 through the intermediary of the i-type layer 3. Here, the GaAs substrate 1 and the Al0.7Ga0.3As layer 2 are doped with Zn by 10<17>cm<-3> or so in dose. And, the i-type ZnSe layer 3 is undoped, and the n-type ZnSe layer 4 is doped with iodine by 10<18>cm<-3> or so in dose. The emitted light rays are blue and an external quantum effciency is 0.7%, so that a luminous efficency is remarkably improved. |
