Pin heterojunction photo diode with undercut gate jifet

This invention provides an opto-electronic integrated circuit for receiving optical signals as well as method for manufacturing the same in which both the receipt sensitivity and reliability are improved to achieve both high operation speed and process simplicity. This is accomplished by integrating the photo-detector and the amplifier on a single chip, which are essential elements of the optical receiver of the optical communication system. Also, layer between a PIN photo-detector and a junction-field effect transistor (JFET) is shared as large as possible through a two times epitaxial growth. In this way, the opto-electronic integrated circuit is optimized.