| 摘要 |
PURPOSE:To enhance the luminous intensity of emitted light by forming a protruding part in an approximately ring shape on a substrate which is located at the outer surface of an electrode, and growing an epitaxial layer. CONSTITUTION:A ring-shaped mesa part (protruding part 7) having the inner diameter of 240mum, the outer diameter 260mum and the height of 20mum is formed on a P-type GaAs substrate 5 having the carrier concentration of 2X10<19>cm<-3> and the thickness of 270mum by photolithography. The ring-shaped mesa parts 7 are aligned in a matrix pattern at the pitch of 400mum on the GaAs substrate 5. A double-heterojunction layer of GaAlAs is grown on the GaAs substrate 5 by a slide board method. A circular N-side electrode 1 is formed on the upper surface of the epitaxial water formed in this way, and a P-side electrode 6 is formed on the rear surface of the substrate 5. The carrier concentration of a P-type GaAlAs clad layer 4 is smaller than that of the P-type GaAs substrate by an order of magnitude or more. The mobility of the layer 4 is also small. Therefore, the resistivity becomes large by two-orders of magnitude. Thus, holes and electrons are concentrated at the mesa part (protruding part 7) and start flowing. Thus the light emitting diode whose luminous intensity of light emission is high can be obtained. |
