PHOTO DETECTOR AND FABRICATION METHOD THEREOF

摘要

PURPOSE: A photo detector and a fabrication method thereof are provided to realize a relatively larger light-receiving area and a smaller capacitance for high response speed. CONSTITUTION: A photo detector includes a lower semiconductor layer(61) doped with n-type, an intrinsic semiconductor layer(63) for receiving incident light, an upper semiconductor layer(65) doped with p-type, which are sequentially formed by epitaxial growth on a substrate(50) doped with n-type. The photo detector further includes a lower electrode(51) formed under the substrate(50) and an upper electrode(53) formed on the upper semiconductor layer(65). In particular, the upper semiconductor layer(65) is formed on only a portion of the intrinsic semiconductor layer(63). Therefore, part of incident light is directly projected to the intrinsic semiconductor layer(63), thereby reducing capacitance of the photo detector.