Patent ID: 8294232

Claim:
An optical detector, comprising: a detector surface operable to receive light; a doping region coupled to the underside of the detector surface, the doping region comprising a first material having a first doping concentration, the doping region having a first width; a depleted field region underlying the doping region, the depleted field region comprising an intrinsic or a near-intrinsic material, the depleted field region operable to support the generation of a hole and an electron from the received light; a charge collection node underlying the depleted field region, the charge collection node having a second width that is less than the first width of the doping region, the charge collection node operable to collect either the hole or the electron generated from the received light; an electrode coupled to the charge collection node; and two or more guard regions coupled to the underside of the detector surface and adjacent to the doping region, the guard regions comprising a second material having a second doping concentration, the guard regions operable to collect either the hole or the electron generated from the received light and to prevent crosstalk to an adjacent optical detector; wherein the second doping concentration of the guard regions is substantially higher than the first doping concentration of the doping region.