Germanium film optical device fabricated on a glass substrate

摘要

A germanium (Ge) photodiode array on a glass substrate is provided with a corresponding fabrication method. A Ge substrate is provided that is either not doped or lightly doped with a first dopant. The first dopant can be either an n or p type dopant. A first surface of the Ge substrate is moderately doped with the first dopant and bonded to a glass substrate top surface. Then, a first region of a Ge substrate second surface is heavily doped with the first dopant. A second region of the Ge substrate second surface is heavily doped with a second dopant, having the opposite electron affinity than the first dopant, forming a pn junction. An interlevel dielectric (ILD) layer is formed overlying the Ge substrate second surface and contact holes are etched in the ILD layer overlying the first and second regions of the Ge substrate second surface. The contact holes are filled with metal and metal pads are formed overlying the contact holes.