US Patent 12132131 Backside illuminated avalanche photodiode and manufacturing method thereof

Provided is a backside illuminated avalanche photodiode and a manufacturing method thereof. The backside illuminated avalanche photodiode comprises a semiconductor substrate; a semiconductor structure including a first semiconductor layer being arranged on a front surface of the semiconductor substrate and including a first conductivity type bottom electrical contact layer, a light absorption layer, and a multiplication layer, and a second semiconductor layer, stacked on the first semiconductor layer and including an etch stop layer and a second conductivity type top electrical conductivity layer stacked on the etch stop layer; a plurality of V-grooves in parallel with each other being formed by etching the top electrical contact layer; and a reflective top electrode formed by depositing a multi layer thin metal films on the top electrical contact layer wherein plurality of V-grooves parallel with each other are formed.