Optical semiconductor integrated circuit device and manufacturing method for the same

Abstract

In an optical semiconductor integrated circuit device in which a vertical pnp transistor and a photodiode are formed, the preferred embodiments of the present invention eliminates difficulty in performance improvement of the two elements. In an illustrative optical semiconductor integrated circuit device, a vertical pnp transistor and a photodiode have been formed, and first and second epitaxial layers and are stacked without doping. This enables a depletion layer forming region to be remarkably increased in the photodiode, and high-speed response becomes possible. Additionally, in the vertical pnp transistor, an n+ type diffusion region surrounds the transistor forming region. This can remarkably improve voltage endurance of the vertical pnp transistor 21.

Dependencies are inferred from the claim text.