| 摘要 |
PURPOSE:To obtain a laser which can operate with a low threshold current by forming directly an electrode having a gap corresponding to a gap of a P type InP region on a P<+> type InP region having higher density than the P type InP layer. CONSTITUTION:A P<+> type InP region 9 is formed in a P type InP layer 4, the contacting resistance of an electrode 1 is reduced to flow a current directly under the part of a gap 1', a P type InP region 8 is formed in an N type InP substrate 7 so as not to extend the current flowing through an active layer 5. Thus, the threshold current can be reduced. |
