Patent ID: 7598482

Claim:
A wavelength-sensitive detector comprising a first photoconductor unit and a second photoconductor unit on a substrate; wherein the first photoconductor unit has a first bandgap and the second photoconductor unit has a second bandgap different from the first bandgap; wherein a plane of the first photoconductor unit and a plane of the second photoconductor unit are substantially parallel to each other and are substantially perpendicular to a plane of the substrate; wherein each photoconductor unit comprises a first electrode having a first longitudinal direction and a first sidewall lying in a first plane parallel with the first longitudinal direction and a second electrode having a second longitudinal direction and a second sidewall lying in a second plane parallel with said second longitudinal direction; wherein the first photoconductor unit comprises a plurality of first type elongated nanostructures positioned in between the first electrode and the second electrode of the first photoconductor unit, the elongated nanostructures each having a longitudinal axis, wherein the longitudinal axes of the first type elongated nanostructures are substantially parallel to each other and are substantially perpendicular to a plane of the first electrode and a plane of the second electrode of the first photoconductor unit; and wherein the second photoconductor unit comprises a plurality of second type elongated nanostructures positioned in between the first electrode and the second electrode of the second photoconductor unit, the elongated nanostructures each having a longitudinal axis, wherein the longitudinal axes of the second type elongated nanostructures are substantially parallel to each other and are substantially perpendicular to a plane of the first electrode and a plane of the second electrode of the second photoconductor unit, wherein the first type elongated nanostructures are of a first material, and a first diameter and a first length, and wherein the second type elongated nanostructures are of a second material, and a second diameter and a second length, wherein at least one of the first material, the first diameter, and the first length is different from the second material, the second diameter, and the second length, wherein the first photoconductor unit is situated in between the substrate and the second photoconductor unit, and wherein the first type elongated nanostructures have a larger bandgap than the second type elongated nanostructures.