OPTICAL SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SAME

摘要

An optical semiconductor device is provided with an n-type epitaxial layer (second epitaxial layer) 24 having a low dopant concentration formed on a low concentration p-type silicon substrate 1; a p-type anode layer (first diffusion layer) 25 having a low dopant concentration selectively formed in the n-type epitaxial layer 24 by means of the ion implantation or the like; a high concentration n-type cathode layer (second diffusion layer) 9 formed on the anode layer 25; a light receiving element 2 comprising the anode layer 25 and the cathode layer 9; and a transistor 3 formed on the n-type epitaxial layer 24. Aphotodiode characterized in its high speed and high receiving sensitivity for light having a short wavelength and a transistor characterized in its high speed can be mounted on the same semiconductor substrate.