Image sensor including visible and near-infrared light detectors and method of manufacturing the same
An image sensor may include visible light detectors and a near-infrared light detector. The near-infrared light detector may contain a material highly sensitive to near-infrared rays, and thus the size of the near-infrared light detector may be reduced.
1. An image sensor comprising:
a plurality of color filters configured to transmit light of different wavelength bands;
a light sensing layer including a plurality of visible light detectors and at least one near-infrared light detector, each of the plurality of visible light detectors and the at least one near-infrared light detector corresponding to one of the plurality of color filters, and a material included in at least one near-infrared light detector includes at least one transition metal dichalcogenide having a transition metal atom and a chalcogen atom; and
a signal processing layer configured to convert an optical signal detected by the light sensing layer into an electric signal.
2. The image sensor of claim 1 , wherein the at least one near-infrared light detector is configured to detect light in a wavelength band ranging from about 800 nm to about 900 nm.
3. The image sensor of claim 1 , wherein the material included in the at least one near-infrared light detector has a band gap of less than or equal to about 1.38 eV.
4. The image sensor of claim 1 , wherein the at least one transition metal dichalcogenide comprises:
at least one of Molybdenum disulfide (MoS 2 ), Molybdenum Selenide (MoSe 2 ), Molybdenum ditelluride (MoTe 2 ), Tungsten diselenide (WSe 2 ), Tungsten(IV) telluride (WTe 2 ), and Hafnium telluride (HfTe 2 ).
5. The image sensor of claim 1 , wherein the at least one near-infrared light detector comprises:
a first layer including the at least one transition metal dichalcogenide; and
a second layer including a semiconductor material.
6. The image sensor of claim 5 , wherein the semiconductor material included in the second layer comprises silicon.
7. The image sensor of claim 1 , wherein the plurality of visible light detectors and the at least one near-infrared light detector are a same size.
8. The image sensor of claim 1 , further comprising:
a common electrode above the light sensing layer with respect to the signal processing layer, and
pixel electrodes in the signal processing layer.
9. The image sensor of claim 1 , wherein a material included in the plurality of visible light detectors includes silicon.
10. An image sensor comprising:
a plurality of color filters configured to transmit light of different wavelength bands;
a light sensing layer including a plurality of visible light detectors and at least one near-infrared light detector, each of the plurality of visible light detectors and the at least one near-infrared light detector corresponding to one of the plurality of color filters, and a material included in at least one near-infrared light detector includes one of (i) at least one transition metal dichalcogenide having a transition metal atom and a chalcogen and (ii) black silicon; and
a signal processing layer configured to convert an optical signal detected by the light sensing layer into an electric signal, wherein
the at least one near-infrared light detector and the plurality of visible light detectors are in a same plane.
11. A method of manufacturing an image sensor, the method comprising:
forming a silicon layer on a signal processing layer;
etching a region of the silicon layer;
arranging a near-infrared light detecting material in the etched region; and
forming a color filter layer on the silicon layer and the near-infrared light detecting material.
12. The method of claim 11 , wherein
the etching includes etching the region of the silicon layer to a partial depth, and
the arranging includes arranging the near-infrared light detecting material in the etched region to the partial depth.
13. The method of claim 11 , wherein the near-infrared light detecting material is configured to detect light in a wavelength band ranging from about 800 nm to about 900 nm.
14. The method of claim 11 , wherein the near-infrared light detecting material comprises:
a material having a band gap of less than or equal to about 1.38 eV.
15. The method of claim 11 , wherein the near-infrared light detecting material comprises:
at least one transition metal dichalcogenide.
16. The method of claim 15 , wherein the near-infrared light detecting material comprises:
at least one of Molybdenum disulfide (MoS 2 ), Molybdenum Selenide (MoSe 2 ), Molybdenum ditelluride (MoTe 2 ), Tungsten diselenide (WSe 2 ), Tungsten(IV) telluride (WTe 2 ), and Hafnium telluride (HfTe 2 ).
17. The method of claim 11 , wherein a material included in the near-infrared light detecting material includes black silicon.