| 摘要 |
PURPOSE:To obtain a high-speed optical integrated circuit, by laminating a light absorbing layer and a light transmitting layer on a semiconductor substrate, forming a photodiode in a part of the layers, using the remaining region of the light transmitting layer as the collector of a transistor, and providing a base and an emitter thereon. CONSTITUTION:An N<-> type InGaAs light absorbing layer 7 and an n-type InP light transmitting layer 8 are laminated on a semi-insulating InP substrate 6. A p-type region 9, in which PIN photodiode 10 is formed by vapor phase diffusion of Zn, is provided. At the inside and the outside of the region 9, an annular p-side electrode 11 and an n-side electrode 12 are provided. The inside of the electrode 11 is made to be a light receiving surface. A part of the light transmitting layer 8, in which the photodiode 10 is not provided, is insulated with a p-type insulating region 21. The part is used as a collector 13 of a hetero- junction bipolar transistor 16. A P-type InGaAsP base 14, a graft base 19, which surrounds the base 14, and an n-type InP emitter 15 are formed. Thereafter, electrodes 17, 20 and 18 for the collector, the base and the emitter are attached to the corresponding regions. Thus an optical IC having a planar structure is obtained. |
