Silicon lateral trench detectors for optical communications

The role of silicon lateral trench detectors (LTD) in fiber optic communication systems was discussed. The LTD is a simple structure that is compatible with CMOS processing. It is composed of a series of parallel trenches alternately filled with p- and n- type polysilicon for the collection of carriers. The array of parallel trenches provides a collecting surface of arbitrary size to collect light from an optical fiber in the same way as with a conventional PIN detector. It was found that a PIN base receiver can out-perform an LTD analog using a simple model based on a parallel plate approximation.