| 摘要 |
PURPOSE:To provide an optical semiconductor device which has a small capacitance between a light-emitting element and a semiconductor substrate and has a good operating characteristic at the high-speed operation. CONSTITUTION:This optical semiconductor device is constituted of a recessed section which has slant faces 2a, 2b and a bottom face 4 and which is formed on the surface of an n-type semiconductor substrate 1, an insulating layer 5 and an electrode 6 for mounting an element, both of which are formed on the bottom face 4, a semiconductor laser element 7 which is located on the electrode 6 through a solder layer, a p-type semiconductor region formed in the n type semiconductor substrate 1 below the semiconductor laser element 7, a pn junction which forms an interface between the p-type semiconductor region and the n-type semiconductor substrate 1, and a photo detector which is formed of an n-type semiconductor region. In this device, the pn junction region formed in the semiconductor substrate and the insulating layer are serially connected. |
