Implementation of an optimized avalanche photodiode (apd)/single photon avalanche diode (spad) structure

Abstract

A semiconductor device, sensor, and array of SPAD cubes are described. One example of the disclosed semiconductor device includes an array of single-photon avalanche diodes, each single-photon avalanche diode including an undepleted anode region, an undepleted cathode region, an active depleted region positioned between the anode region and cathode region, and at least one conductive trench extending between the anode region and cathode region. In some examples, the at least one conductive trench surrounds the active depleted region and reflects light back into the active depleted region such that one or more photons can be absorbed within the active depleted region even though an absorption coefficient of the light is greater than a thickness of the active depleted region.