| 摘要 |
PURPOSE:To improve light emission rate of an element by interposing a multilayer semiconductor layer which is formed by performing lamination to change an effective forbidden band width step by step between a forbidden band width of a clad layer and a forbidden band width of an active layer. CONSTITUTION:An N-type InP clad layer 2, a multilayer semiconductor layer 3 which is formed of a plurality of nondoped InGaAsP crystal films and is formed to change a forbidden band width step by step, an InGaAsP active layer 4 and a P-type InGaAsP cap layer 6 are formed one by one on a surface of an N-type InP substrate 1 by epitaxial growth. Lamination is performed to change an effective forbidden band width step by step between a forbidden band width of the N-type InP clad layer 2 and a forbidden band width of the P-type InGaAsP active layer 4 and the multilayer semiconductor layer 3 is formed. Thereby, it is possible to prevent formation of a P-N junction inside a clad layer, to improve containment of carrier into the active layer and to improve light emission efficiency. |
