Patent ID: 8471353

Claim:
A mesa photodiode comprising: a stack structure that is provided on a semiconductor substrate, said stack structure being formed by stacking and growing a buffer layer comprising a semiconductor of a first conductivity type, an etching stopper layer comprising a semiconductor of the first conductivity type, a second conductivity type, or an undoped type, a light-absorbing layer comprising a semiconductor of the first conductivity type, the second conductivity type, or the undoped type, and a semiconductor layer of the second conductivity type in this order, said semiconductor layer of the second conductivity type and said light-absorbing layer forming a mesa, a side wall of said mesa and at least a shoulder portion of said mesa in an upper face of said mesa being continuously covered with a semiconductor layer of the first conductivity type, the second conductivity type, a semi-insulating type, or the undoped type that is grown on the side wall and the upper face of said mesa, said mesa being covered with a dielectric passivation film through said semiconductor layer, and a layer thickness D 1 of a portion of said semiconductor layer that covers the side wall of said mesa being equal to or greater than 850 nm, wherein said semiconductor layer contacts the side wall of said mesa and at least the shoulder portion of said mesa in the upper face of said mesa.