Photodetector and image sensor including the same

摘要

A photodetector may have a structure including conductive patterns and an intermediate layer interposed between the conductive patterns. A length L of at least one side of the second conductive pattern that overlaps the first conductive pattern and the intermediate layer satisfies the equation L=λ/2neff, wherein the neff is an effective refractive index of a surface plasmon waveguide formed of the first conductive pattern, the intermediate layer, and the second conductive pattern during a surface plasmon resonance. Heat generated in the intermediate layer when the electromagnetic wave having the wavelength λ is incident thereon generates a current variation.

主权项

1. An image sensor, comprising:
a first lower conductive pattern and a second lower conductive pattern spaced apart and physically isolated from each other; an intermediate layer covering the first and second lower conductive patterns, the intermediate layer detecting an electromagnetic wave having a wavelength λ incident thereon; an upper conductive pattern disposed on the intermediate layer, the upper conductive pattern overlapping with a portion of the first lower conductive pattern and a portion of the second lower conductive pattern; and a substrate including a unit pixel area formed of a plurality of sub pixel areas, the first and second lower conductive patterns, the intermediate layer, and the upper conductive pattern being disposed at each of the sub pixel areas, wherein L is a length, a diameter, a portion of a length, or a portion of a diameter of the upper conductive pattern that overlaps one of the first and second lower conductive patterns and satisfies equation 1,
L=λ/2neff   wherein the neff is an effective refractive index of a surface plasmon waveguide formed of the first and second lower conductive patterns, the intermediate layer, and the upper conductive pattern during a surface plasmon resonance, and wherein heat generated in the intermediate layer by the electromagnetic wave through a surface plasmon focusing phenomenon causes a variation in the intermediate layer such that a varied current is detected, and wherein L of an upper conductive pattern and λ of the electromagnetic wave associated with a first sub pixel area are different from L of an upper conductive pattern and λ of the electromagnetic wave associated with a second sub pixel area.