METHOD FOR FORMING A SEMICONDUCTOR DEVICE HAVING A PHOTODETECTOR

摘要

A method is provided for integrating a germanium photodetector with a CMOS circuit. The method comprises: forming first and second isolation regions in a silicon substrate; forming a gate electrode in the first isolation region; implanting source/drain extensions in the silicon substrate adjacent to the gate electrode; forming a first sidewall spacer on the gate electrode; implanting source/drain regions in the silicon substrate; removing the first sidewall spacer from the gate electrode; forming a first protective layer over the first and second isolation regions; removing a portion of the first protective layer to form an opening over the second isolation region; forming a semiconductor material comprising germanium in the opening; forming a second protective layer over the first and second isolation regions; selectively removing the first and second protective layers from the first isolation region; and forming contacts to the transistor and to the semiconductor material.