| 摘要 |
PURPOSE:To display guard ring effect sufficiently in the light receiving element wherein an InP layer is provided on an InGaAsP layer and a light receiving part and a guard ring region are formed thereon, by providing an embedded ion implanted region in the InP layer beneath the light receiving part. CONSTITUTION:On an N<+> type InP substrate 4, an N type InP buffer layer 3, an N type InGaAsP light absorbing layer 2, and an N type InP window layer 7 are layered and epitaxially grown in a liquid phase. Si ions are implanted in a region corresponding to avalanche multiplying region in the layer 7. Thereafter annealing is performed and an electrically activated region 8 is formed. Then an N type InP window layer 9 is layered and grown on the entire surface including the region 8. P type impurities are diffused in the layer 9. The P type light receiving part 10, whose size is larger than the size of the region 8 and the guard ring region 11 which encircles the part 10 in a ring shape are formed. In this constitution, when a high reverse voltage is applied, breakdown occurs in the region 11 quickly, and the damage of the element can be avoided. |
