| 摘要 |
PURPOSE:To obtain a luminous efficiency close to the theoretical value by making an electrode of a P layer of III-V group compound as a three layer structure and settings a Ta layer containing O at the intermediate layer. CONSTITUTION:An N type GaP32 and a P type GaP33 containing Zn and O are layered on an N type GaP substrate 31. An Au-Ge alloy electrode 34 is attached to the substrate 31. Then, an Au-Zn alloy 35 containing 1wt% of Zn and a Ta39, Au35b containing O are piled up on said P layer 33. The formation of the layer 39 is performed by vapor deposition of Ta in O at approximately 10<-4>-10<-6> Torr. After ohm contact by heat treatment, when the etching is performed selectively, the exfoliation of the layers 39 and 35a do not occur. After chippings, the side surface of the P-N junction is made coarse to increase the luminous efficiency and adhered to a header 36 with a conductive paste 37 to join a wire 38. Since the layer 39 disturbs the migration of Zn, Ga, and P at heat treatment, a complex oxide film does not occur on the Au layer 35b, but a good junction is obtained. Further, since the deterioration of the crystallinity of GaP surface can be prevented, the luminous efficiency close to theoretical value is obtained and the yield is also increased. |
