US Patent 11646389 Low dark count rate semiconductor structures

A light sensitive semiconductor structure including a pn-junction in a silicon substrate. The pn-junction includes a central part and an edge part around surrounding the central part, the edge part being in contact with a surface of the silicon substrate. The structure further includes a plasma shielding structure covering at least a depletion width of the pn-junction over at least a part of the edge part where the edge part contacts the surface of the silicon substrate.