SPAD PHOTODIODE OF HIGH QUANTUM EFFICIENCY

摘要

A SPAD-type photodiode has a semiconductor substrate with a light-receiving surface. A lattice formed of interlaced strips made of a first material covers the light receiving surface. The lattice includes lattice openings with lateral walls covered by a spacer made of a second material. Then first and second materials have different optical indices, and further each optical index is less than or equal to the substrate optical index. A pitch of the lattice is of the order of a magnitude of an operating wavelength of the photodiode. The first and second materials are transparent at that operating wavelength. The lattice is made of a conductive material electrically coupled to an electrical connection node (for example, a bias voltage node).

主权项

1. A SPAD-type photodiode, comprising:
a semiconductor substrate having a light-receiving surface; interlaced strips of a first material forming a lattice over said light receiving surface, said first material having a first optical index; at least one spacer of a second material on lateral walls of said interlaced strips, said second material having a second optical index different from the first optical index; wherein said lattice has a pitch of the order of a magnitude of an operating wavelength of the photodiode; wherein the first and second materials are transparent to the operating wavelength; and wherein the first material is conductive and is electrically coupled to an electrical connection node.