KR102430948B1 - Infrared optical sensor and a method for manufacturing the same - Google Patents

Abstract

An infrared optical sensor comprising a substrate, a channel layer on the substrate, light absorbing structures dispersedly disposed on the channel layer, and electrodes disposed on the substrate and disposed on both sides of the channel layer, wherein the The channel layer and the light absorption structures may include a transition metal chalcogen compound.

Description

Infrared optical sensor and manufacturing method thereof

The present invention relates to an infrared light sensor and a method for manufacturing the same, and more particularly, to an infrared light sensor including a transition metal chalcogen compound and a method for manufacturing the same. In particular, it relates to an optical sensor having an improved light absorption effect at a near-infrared wavelength due to a surface plasmon resonance phenomenon in a vertical nanostructure.

A two-dimensional material refers to a material in which the atoms in each layer are bonded by strong ionic or covalent bonds, while the layers are bonded by Van der Waals force, so that the layers are easily separated from each other. do. This two-dimensional material has a very fast mobility because charges move and transfer within one layer. In particular, a 2D semiconductor is a material having excellent electrical, mechanical, and optical properties, and has been spotlighted as a next-generation semiconductor material applicable to flexible and transparent devices.

A transition metal chalcogen compound is a compound composed of a bond between a transition metal element and a chalcogen element, and is a representative two-dimensional material. The transition metal chalcogen compound has a different band gap in a bulk (bulk) state and a monolayer (monolayer) state. That is, it has a characteristic that physical and chemical properties including the band gap change according to the thickness (number of molecular layers).

However, in the case of a single-layer transition metal chalcogen compound having semiconductor properties, there is a limit in light absorption efficiency and wavelength selectivity in the visible light region due to a small specific surface area and an inherent band gap (1.5 eV to 2.0 eV).

The problem to be solved by the present invention is to provide an infrared optical sensor based on a transition metal chalcogen compound including a three-dimensional nanostructure absorber with improved light absorption efficiency and a light absorption wavelength extended to the near-infrared region, and a method for manufacturing the same. .

In addition, there is provided a method of adjusting the absorption wavelength according to plasmon resonance through the binding of the wavelength control element to the nanostructure.

Another object to be solved by the present invention is to provide an infrared optical sensor having improved electrical properties and a method for manufacturing the same.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

Infrared optical sensor according to embodiments of the present invention for solving the above-described technical problems is disposed on the substrate, the channel layer on the substrate, the light absorption structures dispersedly disposed on the channel layer, and the substrate, It may include electrodes disposed on both sides of the channel layer. The channel layer and the light absorbing structures may include a transition metal chalcogen compound.

According to an embodiment, the channel layer may have a two-dimensional crystal structure in which a crystal plane is parallel to the surface of the substrate.

According to an embodiment, the channel layer may be formed of a mono-molecular layer having one molecular layer or a multi-molecular layer having a plurality of molecular layers.

According to an embodiment, the channel layer and the light absorption structures may be made of the same material.

According to an embodiment, the width and height of the light absorption structures may be 1 nm to 10000 nm.

According to an embodiment, a wavelength control element chemically bonded to the surfaces of the light absorbing structures may be further included.

According to an embodiment, the wavelength control element may include hydrogen, oxygen, a chalcogen element, a halogen element, or a transition metal element.

According to an embodiment, the electrodes may include graphene, a metal element, or a metal compound.

In a method for manufacturing an infrared light sensor according to embodiments of the present invention for solving the above technical problems, forming a channel layer on a substrate, growing light absorption structures on an upper surface of the channel layer, and the It may include forming electrodes on both sides of the channel layer on the substrate. Forming the channel layer and forming the light absorption structures is to provide a transition metal element source and a chalcogen element source on one side of the substrate, the vapor of the transition metal element source and the chalcogen element on the substrate supplying the vapor of the source, and applying heat on the substrate.

According to an embodiment, the channel layer and the light absorption structures may be formed in an in-situ manner in which the same process is continuously performed.

According to one embodiment, during the process of forming the channel layer, the vapor of the chalcogen element source has a first partial pressure ratio with respect to the vapor of the transition metal element source, and during the formation process of the light absorption structures, the chalcogen The vapor of the elemental source may have a second partial pressure ratio with respect to the vapor of the transition metal element source. The second partial pressure ratio may be smaller than the first partial pressure ratio.

According to an embodiment, the channel layer and the light absorption structures may be simultaneously formed.

According to an embodiment, the light absorption structures may be locally grown on the channel layer.

According to an embodiment, the channel layer may be formed to have a two-dimensional crystal structure parallel to the upper surface of the substrate by horizontal growth.

According to an embodiment, after forming the light absorption structures, the method may further include bonding a wavelength control element to the surfaces of the light absorption structures.

In one embodiment, combining the wavelength control element may include a plasma deposition process, a chemical vapor deposition (CVD) process, or an atomic layer thin film deposition (ALD) process. The processes may be stopped before the deposited wavelength control element forms a layer.

The infrared light sensor according to embodiments of the present invention may have cluster-shaped light absorbing structures that are locally disposed on the channel layer. The infrared light sensor may absorb light using light absorbing structures, and at the same time may move charges generated by light absorption through the channel layer.

In addition, the infrared light sensor can improve the light absorption ability in the visible light region and the infrared region due to the three-dimensional shape of the light absorbing structure and the local surface plasmon shape generated by the high charge density.

In addition, the infrared light sensor can easily adjust the wavelength band of the light to be absorbed by adjusting the size and amount of the light absorbing structures.

The infrared light sensor may easily control a wavelength band of light to be absorbed by binding a wavelength control element to the surface of the light absorbing structures.

1 is a flowchart illustrating a method of manufacturing an infrared light sensor according to some embodiments of the present invention.
2A to 2D are perspective views illustrating a method of manufacturing an infrared light sensor according to some embodiments of the present invention.
3 is a schematic diagram for explaining a process of forming a channel layer and light absorbing structures.
4A to 4C are photographs of a channel layer and light absorbing structures formed according to Experimental Example 1. Referring to FIG.
5 is a graph showing measurement results of emission spectra according to light excitation of Experimental Examples and Comparative Examples.
6 is a graph showing measurement results of light absorption spectra of Experimental Examples and Comparative Examples.
7 is a graph showing measurement results of photocurrent in Experimental Examples and Comparative Examples.

In order to fully understand the configuration and effects of the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and may be embodied in various forms and various modifications may be made. However, it is provided so that the disclosure of the present invention is complete through the description of the present embodiments, and to fully inform those of ordinary skill in the art to which the present invention belongs, the scope of the invention. Those of ordinary skill in the art will understand that the inventive concept may be practiced in any suitable environment.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural, unless specifically stated otherwise in the phrase. As used herein, 'comprises' and/or 'comprising' refers to the presence of one or more other components, steps, operations and/or elements mentioned. or addition is not excluded.

In this specification, when a film (or layer) is referred to as being on another film (or layer) or substrate, it may be formed directly on the other film (or layer) or substrate, or a third film (or layer) between them. or layer) may be interposed.

In various embodiments of the present specification, the terms first, second, third, etc. are used to describe various regions, films (or layers), etc., but these regions and films should not be limited by these terms. do. These terms are only used to distinguish one region or film (or layer) from another region or film (or layer). Accordingly, a film quality referred to as a first film quality in one embodiment may be referred to as a second film quality in another embodiment. Each embodiment described and illustrated herein also includes a complementary embodiment thereof. Parts indicated with like reference numerals throughout the specification indicate like elements.

Unless otherwise defined, terms used in the embodiments of the present invention may be interpreted as meanings commonly known to those of ordinary skill in the art.

Hereinafter, a method of manufacturing an infrared light sensor according to the concept of the present invention will be described with reference to the drawings. 1 is a flowchart illustrating a method of manufacturing an infrared light sensor according to some embodiments of the present invention. 2A to 2D are perspective views illustrating a method of manufacturing an infrared light sensor according to some embodiments of the present invention. 3 is a schematic diagram for explaining a process of forming a channel layer and light absorbing structures.

1 and 2A , a substrate 10 may be provided. The substrate 10 may be a semiconductor substrate. For example, the substrate 10 may include silicon or silicon oxide. The substrate 10 is not particularly limited as long as it is a substrate used for a general semiconductor device and may be used.

A pretreatment process may be performed on the substrate 10 . For example, the pretreatment process of the substrate 10 may include a heat treatment process. The pretreatment process may be performed to make the chemical reactivity of the surface of the substrate 10 uniform. The pretreatment process of the substrate 10 may not be performed as necessary.

A channel layer 20 may be formed on the substrate 10 ( S1-1 ). The channel layer 20 may be formed by chemically bonding a transition metal element and a chalcogen element on the substrate 10 . For example, the channel layer 20 may be formed using thermal evaporation. Hereinafter, an embodiment of the forming process ( S1-1 ) of the channel layer 20 will be described in more detail.

2A and 3 , a chamber 100 may be provided. The interior of the chamber 100 may be provided in a vacuum state. For example, the vacuum pump 110 may be connected to one side of the chamber 100 . The chamber 100 may have a first region R1 and a second region R2 . As will be described later, a vaporization reaction may occur in the first region R1 , and vaporization and deposition reactions may occur in the second region R2 . A carrier gas 120 may be injected into the chamber 100 . The carrier gas 120 may flow from the first region R1 toward the second region R2 . For example, the carrier gas 120 may include arcon (Ar). The first heating unit 210 and the second heating unit 220 may be provided outside the chamber 100 . The first heating unit 210 may provide heat to the first region R1 , and the second heating unit 220 may provide heat to the second region R2 .

A substrate 10 may be provided in the chamber 100 . The substrate 10 may be provided in the second region R2 of the chamber 100 . A transition metal element source 300 and a chalcogen element source 400 may be provided in the chamber 100 . The transition metal element source 300 may be provided in the second region R2 of the chamber 100 , and the chalcogen element source 400 may be provided in the first region R1 of the chamber 100 . The transition metal element source 300 and the chalcogen element source 400 may be provided in powder form, but the present invention is not limited thereto. The transition metal element source 300 is Ti, Mo, V, Mn, Cr, Fe, Ni, Cu, Co, Nb, Ta, W, Nb, Tc, Re, Ru, Os, Rh, Ir, Ag, Au, Pt, Cd, In, Tl, Sn, Pb, Sb, Bi, Zr, Te, Pd, Hf, or a compound thereof. For example, the transition metal element source 300 is (NH ₄ ) ₂ MoS ₄ , (NH ₄ ) ₆ Mo ₇ O ₂₄ .4H ₂ , ((CH ₃ ) ₄ N) ₂ MoS ₄ , ((C ₂ H) ₅ ) ₄ N) ₂ MoS ₄ , Mo(CO) ₆ , MoCl ₅ , MoOCl ₄ or MoO ₃ . The chalcogen element source 400 may include an organic compound or an inorganic compound containing element sulfur (S). For example, the chalcogen element source 400 is H ₂ S, CS ₂ , SO ₂ , S ₂ , (NH ₄ ) ₂ S, C ₆ H ₈ OS, S(C ₆ H ₄ NH ₂ ) ₂ or Na ₂ SH ₂ O.

The first vapor 310 and the second vapor 410 may be supplied on the substrate 10 . The first vapor 310 may be a vapor in which the transition metal source 300 is vaporized, and the second vapor 410 may be vapor in which the chalcogen element source 400 is vaporized. For example, the transition metal element source 300 may be vaporized using the second heating unit 220 , and the chalcogen element source 400 may be vaporized using the first heating unit 210 . The first vapor 310 and the second vapor 410 may diffuse onto the substrate 10 or may move onto the substrate 10 by the carrier gas 120 . The first vapor 310 may be provided in the chamber 100 at a first partial pressure pp1 , and the second vapor 410 may be provided in the chamber 100 at a second partial pressure pp2 . Amounts of the first vapor 310 and the second vapor 410 supplied to the substrate 10 may be adjusted according to the first partial pressure pp1 and the second partial pressure pp2 . For example, the first steam 310 and the second steam 410 generated from the sources 300 and 400 by changing the amount of heat supplied by the first heating unit 210 and the second heating unit 220 . ), that is, the first partial pressure pp1 and the second partial pressure pp2 may be adjusted. Alternatively, the amounts of the first vapor 310 and the second vapor 410 are adjusted by changing the distance between the substrate 10 and the transition metal element source 300 or the distance between the substrate 10 and the chalcogen element source 400 . can be For example, by disposing the transition metal element source 300 and the chalcogen element source 400 adjacent to the substrate 10 , the first vapor 310 and the second vapor 410 provided on the substrate 10 . can increase the amount of

The first vapor 310 and the second vapor 410 may react to form the channel layer 20 on the substrate 10 . For example, seeds are formed on the surface of the substrate 10 through a gas phase reaction between the first vapor 310 and the second vapor 410 , and the seeds grow horizontally to form a channel. A layer 20 may be formed. In order to improve the reactivity of the first vapor 310 and the second vapor 410 , heat may be provided to the substrate 10 using the second heating unit 220 . The channel layer 20 may include a transition metal dichalcogenide. The channel layer 20 may have a two-dimensional crystal structure. Here, the two-dimensional crystal structure refers to a crystal structure having a layered structure in which bonds between constituent atoms are formed only on a two-dimensional plane, and weak van der Waals bonds are formed between molecular layers formed by constituent atoms. The molecular layer of the channel layer 20 may be parallel to the top surface of the substrate 10 . That is, the channel layer 20 may have a structure in which molecular layers thereof are stacked in a direction perpendicular to the substrate 10 . The channel layer 20 may be formed as a mono-molecular layer having one molecular layer or as a multi-molecular layer having a plurality of molecular layers. As described above, the channel layer 20 may be formed on the substrate 10 .

1 and 2B , light absorption structures 30 may be grown on the upper surface of the channel layer 20 ( S1 - 2 ). A process for forming the light absorbing structures 30 may be the same as/similar to a process for forming the channel layer 20 . As an example, partially with reference to FIG. 3 , the substrate 10 on which the channel layer 20 is formed in the chamber 100 , the transition metal element source 300 , and the chalcogen element source 400 may be provided. By heating the transition metal element source 300 and the chalcogen element source 400 , the first vapor 310 and the second vapor 410 may be supplied on the substrate 10 . In the forming process ( S1 - 2 ) of the light absorption structures 30 , the first vapor 310 is provided in the chamber 100 at a third partial pressure pp3 , and the second vapor 410 is supplied to the chamber 100 . It may be provided at the fourth partial pressure (pp4) in the . Light absorption structures 30 may be formed on the channel layer 20 by reacting the first vapor 310 and the second vapor 410 . In this case, the partial pressure ratio of the third partial pressure pp3 to the fourth partial pressure pp4 (=pp4/pp3) is higher than the partial pressure ratio of the first partial pressure pp1 to the second partial pressure pp2 (=pp2/pp1). can be small That is, the ratio of the second vapor 410 may be smaller in the forming process ( S1 - 2 ) of the light absorption structures 30 than in the forming process ( S1-1 ) of the channel layer 20 . As the ratio of the second vapor 410 containing the chalcogen element is lower, the surface energy of the generated transition metal chalcogen compound may be increased, and a large-scale transition on the upper surface of the channel layer 20 may be obtained. A metal chalcogen compound cluster (cluster) may be formed. Here, the cluster refers to an aggregate in which a plurality (eg, several to hundreds) of atoms or molecules are gathered. The light absorbing structures 30 in a cluster shape may be formed on the upper surface of the channel layer 20 through the above process. The light absorption structures 30 may be locally formed on the upper surface of the channel layer 20 . The amount of the light absorbing structures 30 formed and the size of the formed light absorbing structures 30 are determined by the partial pressure ratio between the first vapor 310 and the second vapor 410 supplied on the substrate 10 , the process It can be controlled through the temperature or the distance between the transition metal element and the substrate 10 .

According to embodiments, the process ( S1-1 ) of forming the channel layer 20 and the process ( S1 - 2 ) of forming the light absorption structures 30 are in-situ continuously performing the same process. -situ) may be used. For example, in the process ( S1 - 2 ) of forming the light absorption structures 30 , the first vapor 310 and the second vapor 410 are formed in the same chamber 100 after the channel layer 20 is formed. This can be done by changing the partial pressure ratio and the process temperature.

Alternatively, the channel layer 20 and the light absorption structures 30 may be simultaneously formed. That is, the process ( S1-1 ) of forming the channel layer 20 and the process ( S1 - 2 ) of forming the light absorption structures 30 may be one process. Depending on the partial pressure ratio of the first vapor 310 and the second vapor 410 and the process temperature, the channel layer 20 and the light absorption structures 30 may grow simultaneously. For example, as the process temperature increases, the channel layer 20 growing in two dimensions may be easily formed due to the surface diffusion effect, and the partial pressure of the second vapor 410 is reduced to form light absorbing structures ( 30) may be formed simultaneously.

In the above, the method of forming the channel layer 20 and the light absorption structures 30 has been described, but the present invention is not limited thereto. For example, the channel layer 20 and the light absorption structures 30 may be formed through various vapor deposition methods such as plasma-enhanced chemical vapor deposition (PeCVD) or thermal-CVD.

1 and 2C , a wavelength control element 40 may be coupled to the surface of the light absorption structures 30 ( S2 ). The wavelength control element 40 may be chemically bonded to the surface of the light absorbing structures 30 . Here, the wavelength control element 40 bonded to the surface of the light absorbing structures 30 may be a single atom or a single molecule, or otherwise, may be in the form of a particle having a plurality of atoms or molecules. The wavelength control element 40 may be coupled to the surface of the light absorbing structures 30 through plasma deposition, chemical vapor deposition (CVD), heat treatment, or atomic layer thin film deposition (ALD). can In this case, the deposition processes may be stopped before the wavelength control element 40 forms a layer on the surface of the light absorption structures 30 . The wavelength control element 40 may include hydrogen, oxygen, a chalcogen element, a halogen element, or a transition metal element.

1 and 2D , electrodes 50 may be formed on the substrate 10 ( S3 ). The electrodes 50 may be formed on both sides of the channel layer 20 . For example, the electrodes 50 may be formed by transferring graphene to both sides of the channel layer 20 , or may be formed by patterning after forming a conductive layer. The electrodes 50 may include graphene, a metal, or a metal compound.

Referring to FIG. 2D , the infrared light sensor may include a substrate 10 , a channel layer 20 , light absorption structures 30 , and electrodes 50 .

The substrate 10 may include a semiconductor substrate. For example, the substrate 10 may include silicon or silicon oxide.

A channel layer 20 may be disposed on the substrate 10 . The channel layer 20 may be made of a semiconductor material having a two-dimensional crystal structure. For example, the channel layer 20 may include a transition metal chalcogen compound. The molecular layer of the channel layer 20 may be parallel to the upper surface of the substrate. The channel layer 20 may be a mono-molecular layer having one molecular layer or a multi-molecular layer having a plurality of molecular layers.

Light absorption structures 30 may be disposed on the channel layer 20 . The light absorption structures 30 may be dispersedly disposed on the upper surface of the channel layer 20 . The light absorbing structures 30 may have a cluster shape. For example, the light absorbing structures 30 may have a nano flake or nano plate shape. The width and height of the light absorption structures 30 may be 1 nm to 10000 nm. The light absorption structures 30 may be made of the same material as the channel layer 20 . For example, the light absorption structures 30 may include a transition metal chalcogen compound.

According to embodiments of the present invention, the infrared light sensor may have cluster-shaped light absorbing structures 30 that are locally disposed on the channel layer 20 that is a two-dimensional semiconductor. The cluster-shaped light absorbing structures 30 may have defects in chemical bonding between atoms on their surface. Accordingly, the surface of the light absorbing structures 30 may have a high electron density, and localized surface plasmon resonance may occur. That is, the infrared light sensor may absorb light using the light absorption structures 30 , and may move charges generated by light absorption through the channel layer 20 .

In addition, the resonance frequency of the local surface plasmon resonance may vary according to the size, amount, and charge concentration of the light absorbing structures 30 . That is, the infrared light sensor may adjust the wavelength band of the light to be absorbed by adjusting the size, amount, and charge concentration of the light absorption structures 30 .

A wavelength adjusting element 40 may be coupled to the surface of the light absorbing structures 30 . The wavelength control element 40 may physically or chemically bond to the defects on the surface of the light absorbing structures 30 . The wavelength control element 40 is coupled to the surface of the light absorption structures 30 , so that the electron density of the surface of the light absorption structures 30 may be increased or decreased. Accordingly, the resonance frequency of the local surface plasmon resonance may vary. That is, the infrared light sensor may adjust the wavelength band of light to be absorbed by binding the wavelength control element 40 to the surface of the light absorption structures 30 .

Electrodes 50 may be disposed on the substrate 10 . The electrodes 50 may be disposed on both sides of the channel layer 20 . The electrodes 50 may include graphene, a metal, or a metal compound.

Experimental Example 1

A silicon substrate was used as the substrate. MoO ₃ was used as the transition metal element source, and sulfur (S) powder was used as the chalcogen element source. After the substrate, the transition metal element source and the chalcogen element source were placed in the chamber, the interior of the chamber was maintained in a vacuum. Thereafter, after injecting a carrier gas into the chamber, heat was applied to the chamber to form a channel layer and light absorption structures on the substrate. The channel layer was formed to have a single molecular layer of MoS ₂ , and the light absorption structures were formed to have MoS ₀ grown vertically on the surface of the channel layer. Thereafter, graphene electrodes were formed on both sides of the channel layer to prepare an infrared light sensor. Infrared light sensors are manufactured to absorb light in the infrared region.

Experimental example 2

A plasma deposition process using oxygen was performed on the result of Experimental Example 1, and a wavelength control element was bonded to the surface of the light absorbing structures. Oxygen was used as the wavelength control element.

comparative example

It was formed in the same manner as in Experimental Example 1, except that light absorbing structures were not formed on the channel layer.

4A to 4C are photographs of a channel layer and light absorbing structures formed according to Experimental Example 1. Referring to FIG. 4A is an infrared light sensor in which the channel layer 20a and the light absorbing structures 30a are formed in a state where the transition metal source and the substrate are spaced 0 cm apart, and FIG. 4B is the transition metal source and the substrate are spaced 3 cm apart. It is an infrared light sensor in which the channel layer 20b and the light absorbing structures 30b are formed, and FIG. 4C shows the channel layer 20c and the light absorbing structures 30c in a state where the gap between the transition metal source and the substrate is 6 cm. It is an infrared light sensor that has formed Referring to FIGS. 4A to 4C , it can be seen that the channel layers 20a, 20b, and 20c and the light absorption structures 30a, 30b, and 30c are formed. That is, it can be seen that the method of manufacturing the infrared light sensor of the present invention can control the amount of the infrared light absorbing structures formed by adjusting the distance between the transition metal source and the substrate in the chamber.

5 is a graph showing measurement results of emission spectra according to light excitation of Experimental Examples and Comparative Examples. After irradiating a laser having a wavelength of 532 nm to Experimental Examples and Comparative Examples, the energy of the emitted light was measured. Referring to FIG. 5 , in the single-layer MoS ₂ , excitons A and B excitons having an energy of 2.02 eV by spin orbital split of the valence band are formed by light excitation at K, K′ points of the Brillion zone by incident light. A exciton is divided into A0 exciton having an energy of 1.85 eV, which is formed by combining one electron and one hole, and A- exciton, having an energy of 1.88 eV, formed by combining two electrons and one hole. A- exciton is related to the electron concentration, and as the electron concentration increases, the peak caused by A- exciton increases. Referring to FIG. 5 , in Experimental Example 1, it can be seen that the size of A- excitons in the vertical structure increased compared to the size of A- excitons in the horizontal region of MoS ₂ . In addition, in Experimental Example 2, it can be seen that the size of A- excitons is further increased compared to Experimental Example 1. As a result of calculating the charge concentration in the vertical structure through the charge quantity conservation law using the spectrum analysis result according to the measurement in FIG. 5 , according to the presence or absence of oxygen plasma, 3X10 ²⁰ cm ^-3 of Experimental Example 1 to 9X10 ²⁰ of Experimental Example 2 It can be seen that it increases with cm ^-3 . This reflects that the charge concentration in the nanostructure increases with the binding of oxygen. In general, the wavelength of local surface plasmon resonance in a semiconductor is due to the charge concentration of the semiconductor. In the case of a two-dimensional transition metal chalcogen compound having semiconductor properties, a local surface plasmon resonance may occur in the far ^- infrared or terahertz region with a charge concentration of 10 ¹² cm ^-3 to ^{10 14} cm -3 in general. Therefore, in order to generate local surface plasmon resonance in the visible or near-infrared wavelength region, a charge concentration of 10 ²⁰ cm ^-3 or more is required. In the case of MoS ₂ having a nanostructure treated with oxygen plasma according to embodiments of the present invention, since it has a charge concentration of 9X10 ²⁰ cm ^-3 , it is shown that plasmon resonance can occur in the near-infrared region of about 960 nm. can be predicted through

6 is a graph showing measurement results of light absorption spectra of Experimental Examples and Comparative Examples. The amount of absorbed light was measured by irradiating light having a wavelength of 200 nm to 1200 nm to Experimental Example 1, Experimental Example 2, and Comparative Example. Referring to FIG. 6 , in the case of the comparative example, a very low absorption peak is shown at a wavelength of 300 nm to 500 nm of the incident light, and an absorption peak does not appear in other wavelength regions. On the other hand, Experimental Example 1 and Experimental Example 2 also showed a high absorption peak at a wavelength of 800 nm to 1000 nm of incident light corresponding to infrared rays. That is, it can be confirmed that the infrared light sensor of the present invention exhibits a high absorption rate for light having a wavelength to be absorbed. In addition, in the case of Experimental Example 2, the absorption peak was found at a lower wavelength than Experimental Example 1. In Experimental Example 1 and Experimental Example 2, it can be confirmed that the central wavelength by plasmon resonance in the near-infrared region is about 1000 nm and 950 nm, respectively. That is, in the case of Experimental Example 2, the absorption peak was found at a lower wavelength than Experimental Example 1. This means that, with reference to FIG. 5 , Experimental Example 2 has a higher charge concentration than Experimental Example 1, thereby generating plasmon resonance at a lower wavelength. That is, it can be seen that the infrared light sensor of the present invention can control the absorption wavelength through the wavelength control element.

7 is a graph showing measurement results of photocurrent in Experimental Example 1 and Comparative Example. After irradiating light having wavelengths of 532 nm, 672 nm and 1064 nm to Experimental Example 1 and Comparative Example, the photocurrent flowing between the electrodes was measured. Referring to FIG. 7 , for light of each wavelength, a higher photocurrent was measured in Experimental Example 1 than in Comparative Example. It can be seen that in Experimental Example 1, the light absorption ability is improved due to the high specific surface area, and local plasmon resonance occurs due to the high charge concentration. Accordingly, in Experimental Example 1, absorption in the near-infrared region increased, which means that the photocurrent increased compared to Comparative Example. That is, it can be confirmed that the infrared light sensor of the present invention has high sensitivity in the near-infrared region as well as the visible light.

In the above, embodiments of the present invention have been described with reference to the accompanying drawings, but those of ordinary skill in the art to which the present invention pertains can practice the present invention in other specific forms without changing its technical spirit or essential features. You will understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

10: substrate 20: channel layer
30: light absorption structure 40: wavelength control element
50: electrode

Claims (15)

Board;
a channel layer on the substrate;
light absorbing structures dispersedly disposed on the channel layer;
electrodes disposed on the substrate and disposed on both sides of the channel layer; and
a wavelength control element chemically bonded to the surfaces of the light absorbing structures;
including,
The channel layer and the light absorbing structures are infrared light sensor comprising a transition metal chalcogen compound.
The method of claim 1,
The channel layer is an infrared optical sensor having a two-dimensional crystal structure in which a crystal plane is parallel to the surface of the substrate. 3. The method of claim 2,
The channel layer is an infrared optical sensor composed of a mono-molecular layer having one molecular layer or a multi-molecular layer having a plurality of molecular layers. The method of claim 1,
and the channel layer and the light absorbing structures are made of the same material. The method of claim 1,
An infrared light sensor having a width and a height of 1 nm to 10000 nm of the light absorbing structures. delete The method of claim 1,
The wavelength control element is an infrared light sensor comprising hydrogen, oxygen, a chalcogen element, a halogen element or a transition metal element.

forming a channel layer on the substrate;
growing light absorbing structures on the upper surface of the channel layer;
coupling a wavelength control element to the surface of the light absorbing structures; and
forming electrodes on both sides of the channel layer on the substrate;
including,
Forming the channel layer and forming the light absorption structures include:
providing a transition metal element source and a chalcogen element source on one side of the substrate;
supplying the vapor of the transition metal element source and the vapor of the chalcogen element source on the substrate; and
applying heat to the substrate;
A method of manufacturing an infrared light sensor comprising a.
9. The method of claim 8,
The method of manufacturing an infrared optical sensor in which the channel layer and the light absorption structures are formed in an in-situ manner in which the same process is continuously performed. 10. The method of claim 9,
In the process of forming the channel layer, the vapor of the chalcogen element source has a first partial pressure ratio with respect to the vapor of the transition metal element source,
In the process of forming the light absorption structures, the vapor of the chalcogen element source has a second partial pressure ratio with respect to the vapor of the transition metal element source,
and the second partial pressure ratio is smaller than the first partial pressure ratio. 9. The method of claim 8,
The method of manufacturing an infrared light sensor in which the channel layer and the light absorption structures are simultaneously formed. 9. The method of claim 8,
The method of manufacturing an infrared light sensor in which the light absorption structures are locally grown on the channel layer. 9. The method of claim 8,
The channel layer is horizontally grown to have a two-dimensional crystal structure parallel to the upper surface of the substrate. delete 9. The method of claim 8,
Incorporating the wavelength control element comprises a plasma deposition process, a chemical vapor deposition (CVD) process, or an atomic layer thin film deposition (ALD) process.

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