Electromagnetic wave detector and electromagnetic wave detector assembly

Abstract

An electromagnetic wave detector (100) is provided with a semiconductor layer (4), a first insulating film (3a), a two-dimensional material layer (1), a first electrode (2a), a second electrode (2b), a second insulating film (3b), and a control electrode (2c). The first insulating film (3a) is disposed on the semiconductor layer (1). An opening portion (OP) is formed in the first insulating film (3a). The two-dimensional material layer (1) is electrically connected to the semiconductor layer (4) at the opening portion (OP). The two-dimensional material layer (1) extends from the opening portion (OP) up to the first insulating film (3a). The second insulating film (3b) is in contact with the two-dimensional material layer (1). The control electrode (2c) is connected to the two-dimensional material layer (1) with the second insulating film (3b) interposed therebetween.

Description

Technical Field

[0001] This disclosure relates to electromagnetic wave detectors and electromagnetic wave detector assemblies. Background Technology

[0002] Graphene is known as an example of a two-dimensional material layer for electromagnetic wave detection layers used in next-generation electromagnetic wave detectors. Graphene exhibits extremely high mobility and an absorption rate as low as 2.3%. Therefore, methods have been proposed to improve the sensitivity of electromagnetic wave detectors using graphene as a two-dimensional material layer.

[0003] For example, U.S. Patent Application Publication 2015 / 0243826 discloses a detector with the following structure: Two or more dielectric layers are disposed on an n-type semiconductor layer. A graphene layer is formed on the two dielectric layers and on the surface portion of the n-type semiconductor layer located between the two dielectric layers. Source / drain electrodes connected to both ends of the graphene layer are disposed on the dielectric layers. A gate electrode is connected to the n-type semiconductor layer.

[0004] In the aforementioned detector, a voltage is applied to the graphene layer, which serves as the channel, via the source / drain electrodes. As a result, photocarriers generated in the n-type semiconductor layer are amplified, thus increasing the detector's sensitivity. Furthermore, by applying a voltage to the gate electrode and either the source or drain electrode, the detector can be switched off via the Schottky connection between the graphene and the n-type semiconductor layer. This detector detects high-energy electromagnetic waves exceeding the difference between the Fermi level of the graphene layer and the Fermi level of the n-type semiconductor layer in contact with the graphene layer.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: U.S. Patent Application Publication No. 2015 / 0243826 Summary of the Invention

[0008] The technical problem that the invention aims to solve

[0009] The detector (electromagnetic wave detector) described in the aforementioned announcement cannot change the Fermi level of the graphene layer (two-dimensional material layer) from the Fermi level at the time of graphene layer formation. Therefore, for example, a proper Schottky barrier cannot be formed depending on the deposition state of the graphene layer. Consequently, the detector is sometimes unable to detect the electromagnetic waves that are the object of the detector.

[0010] This disclosure is made in view of the above-mentioned technical issues, and its purpose is to provide an electromagnetic wave detector and an electromagnetic wave detector assembly capable of changing the Fermi level of a two-dimensional material layer.

[0011] Technical solutions for solving technical problems

[0012] The electromagnetic wave detector disclosed herein includes a semiconductor layer, a first insulating film, a two-dimensional material layer, a first electrode, a second electrode, a second insulating film, and a control electrode. The first insulating film is disposed on the semiconductor layer. An opening is formed in the first insulating film. The two-dimensional material layer is electrically connected to the semiconductor layer at the opening. The two-dimensional material layer extends from the opening to the first insulating film. The first electrode is electrically connected to the two-dimensional material layer. The second electrode is electrically connected to the semiconductor layer. The second insulating film is in contact with the two-dimensional material layer. The control electrode is connected to the two-dimensional material layer through the second insulating film.

[0013] Invention Effects

[0014] According to the electromagnetic wave detector disclosed herein, the Fermi level of a two-dimensional material layer can be changed. Attached Figure Description

[0015] Figure 1 A cross-sectional view of the first structure of the electromagnetic wave detector of Embodiment 1 is shown for schematic purposes.

[0016] Figure 2 A top view of the first structure of the electromagnetic wave detector of Embodiment 1 is shown for schematic purposes.

[0017] Figure 3 A top view of the second structure of the electromagnetic wave detector of Embodiment 1 is shown for schematic purposes.

[0018] Figure 4 A cross-sectional view of the third structure of the electromagnetic wave detector of Embodiment 1 is shown for schematic purposes.

[0019] Figure 5 A cross-sectional view of the fourth structure of the electromagnetic wave detector of Embodiment 1 is shown for schematic purposes.

[0020] Figure 6 The energy band diagrams of the Fermi levels of the two-dimensional material layer and the semiconductor layer are shown schematically in the state where a Schottky barrier is formed.

[0021] Figure 7 The energy band diagrams of the Fermi levels of the two-dimensional material layer and the semiconductor layer are shown schematically without the formation of the Schottky barrier.

[0022] Figure 8 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 2 is shown for schematic purposes.

[0023] Figure 9 For the purposes of illustration, the first structure of the electromagnetic wave detector of Embodiment 3 is shown, and... Figure 2 An enlarged view of the region corresponding to region IX.

[0024] Figure 10 The second structure of the electromagnetic wave detector in Embodiment 3 is shown schematically, and... Figure 9 The corresponding top view.

[0025] Figure 11 The third structure of the electromagnetic wave detector in Embodiment 3 is shown schematically, and... Figure 9 The corresponding top view.

[0026] Figure 12 The fourth structure of the electromagnetic wave detector in Embodiment 3 is shown schematically, and... Figure 9 The corresponding top view.

[0027] Figure 13 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 4 is shown for schematic purposes.

[0028] Figure 14 A top view of the structure of the electromagnetic wave detector of Embodiment 5 is shown for schematic purposes.

[0029] Figure 15 A top view of the structure of the electromagnetic wave detector of Embodiment 6 is shown for schematic purposes.

[0030] Figure 16 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 7 is shown for schematic purposes.

[0031] Figure 17 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 8 is shown for schematic purposes.

[0032] Figure 18 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 9 is shown for schematic purposes.

[0033] Figure 19 A top view of the structure of the electromagnetic wave detector of Embodiment 9 is shown for schematic purposes.

[0034] Figure 20 A cross-sectional view of the structure of the electromagnetic wave detector of the first variation of Embodiment 9 is shown for schematic purposes.

[0035] Figure 21 A cross-sectional view of the structure of the electromagnetic wave detector of the second variation of Embodiment 9 is shown for schematic purposes.

[0036] Figure 22 A top view of the structure of the electromagnetic wave detector of the second variation of Embodiment 9 is shown for schematic purposes.

[0037] Figure 23 A cross-sectional view of the structure of the electromagnetic wave detector of the third variation of Embodiment 9 is shown for schematic purposes.

[0038] Figure 24 A top view of the structure of the electromagnetic wave detector of the third variation of Embodiment 9 is shown for schematic purposes.

[0039] Figure 25 A top view of the structure of the electromagnetic wave detector of Embodiment 10 is shown for schematic purposes.

[0040] Figure 26 A top view is shown for schematic purposes, illustrating the structure of the plurality of opening portions of the electromagnetic wave detector of Embodiment 10.

[0041] Figure 27 A top view of other structures of the plurality of opening portions of the electromagnetic wave detector of Embodiment 10 is shown for schematic purposes.

[0042] Figure 28 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 11 is shown for schematic purposes.

[0043] Figure 29 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 12 is shown for schematic purposes.

[0044] Figure 30 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 13 is shown for schematic purposes.

[0045] Figure 31 A cross-sectional view of the structure of the electromagnetic wave detector of a modified embodiment 13 is shown for schematic purposes.

[0046] Figure 32 A cross-sectional view of the structure of the electromagnetic wave detector of Embodiment 14 is shown for schematic purposes.

[0047] Figure 33 A top view of the structure of the electromagnetic wave detector assembly of Embodiment 16 is shown for schematic purposes.

[0048] Figure 34 A cross-sectional view is shown for schematic purposes, illustrating the structure of one of the plurality of electromagnetic wave detectors, the pad, the bump, and the readout circuitry included in the electromagnetic wave detector assembly of Embodiment 16.

[0049] Figure 35 A top view of the structure of the electromagnetic wave detector assembly of a modified embodiment 16 is shown for schematic purposes.

[0050] Figure 36 A top view of the structure of the electromagnetic wave detector of Embodiment 17 is shown for schematic purposes.

[0051] Figure 37 A top view of the structure of the electromagnetic wave detector of the first variation of Embodiment 17 is shown for schematic purposes.

[0052] Figure 38 A top view of the structure of the electromagnetic wave detector of the second variation of Embodiment 17 is shown for schematic purposes.

[0053] Figure Labels

[0054] 1: Two-dimensional material layer; 1a: Part 1; 1b: Part 2; 2a: First electrode; 2aa: First edge; 2ab: Second edge; 2b: Second electrode; 2c: Control electrode; 2c0: Control electrode part; 2c1: First control electrode part; 2c2: Second control electrode part; 3a: First insulating film; 3a1: Tapered part; 3b: Second insulating film; 4: Semiconductor layer; 5: Buffer layer; 6: Connecting conductor; 8: Contact layer; 11: First end; 12: Second end; 41: First semiconductor part; 42: Second semiconductor part; 100: Electromagnetic wave detector; 200: Electromagnetic wave detector assembly; DR1: First direction; DR2: Second direction; GAP: Gap; OP: Opening. Detailed Implementation

[0055] The embodiments are described below based on the accompanying drawings. Furthermore, the same or equivalent parts will be referred to by the same reference numerals, and will not be described repeatedly.

[0056] In the embodiments described below, the accompanying drawings are schematic and conceptually illustrate the function or structure. Furthermore, this disclosure is not limited to the embodiments described below. Except where specifically stated, the basic structure of the electromagnetic wave detector is the same in all embodiments. Additionally, elements with the same reference numerals are the same or equivalent elements as described above. This is consistent throughout the specification.

[0057] In the embodiments described below, although the structure of the electromagnetic wave detector for detecting visible or infrared light is described, the electromagnetic wave detector of this disclosure is not limited to visible and infrared light. In addition to detecting visible and infrared light, the embodiments described below are also effective as detectors for detecting radio waves such as X-rays, ultraviolet light, near-infrared light, terahertz (THz) waves, and microwaves. Furthermore, in the embodiments of this disclosure, these lights and radio waves are collectively referred to as electromagnetic waves.

[0058] Furthermore, in this embodiment, the terms p-type graphene and n-type graphene are sometimes used as graphene. In the following embodiments, graphene with more holes than intrinsic graphene is called p-type graphene, and graphene with more electrons than intrinsic graphene is called n-type graphene.

[0059] Furthermore, when the charge is polarized within the molecule as a whole, electron-dominated molecules are sometimes referred to as n-type. When the charge is polarized within the molecule as a whole, hole-dominated molecules are sometimes referred to as p-type. As a material for components in contact with graphene, an example of a two-dimensional material layer, any one of organic and inorganic materials, or a mixture of organic and inorganic materials, can be used.

[0060] Furthermore, plasmonic resonance phenomena, such as surface plasmonic resonance phenomena involving the interaction of a metal surface with light, phenomena referred to as pseudo-surface plasmonic resonances in the sense of resonances involving metal surfaces outside the visible and near-infrared light ranges, and phenomena referred to as metamaterials or plasma metamaterials in the sense of manipulating wavelengths using sub-wavelength structures, are not specifically distinguished by name, but are treated equally based on the effects they cause. Here, these resonances are referred to as surface plasmonic resonances, plasmonic resonances, or simply resonances.

[0061] Furthermore, in the embodiments described below, graphene is used as an example as the material for the two-dimensional material layer, but the material for the two-dimensional material layer is not limited to graphene. For example, transition metal dichalcogenides (TMD), black phosphorus, silicene (a two-dimensional honeycomb structure based on silicon atoms), and germanene (a two-dimensional honeycomb structure based on germanium atoms) can be used as materials for the two-dimensional material layer. Examples of transition metal dichalcogenides include molybdenum disulfide (MoS2), tungsten disulfide (WS2), and tungsten diselenide (WSe2).

[0062] These materials have a structure similar to graphene. In these materials, atoms are arranged in a single layer within a two-dimensional plane. Therefore, applying these materials to a two-dimensional material layer yields the same effect as applying graphene to a two-dimensional material layer.

[0063] Furthermore, in this embodiment, the structure described as an insulating layer is a layer of insulating material with a thickness that does not generate tunneling current. Additionally, the structure described as a blocking layer is a layer of insulating material with a thickness that generates tunneling current.

[0064] Implementation method 1.

[0065] <Structure of Electromagnetic Wave Detector 100>

[0066] use Figures 1-5 The structure of the electromagnetic wave detector 100 in Embodiment 1 will be explained.

[0067] like Figure 1 As shown, the electromagnetic wave detector 100 includes a two-dimensional material layer 1, a first electrode 2a, a second electrode 2b, a control electrode 2c, a first insulating film 3a, a second insulating film 3b, and a semiconductor layer 4.

[0068] A first insulating film 3a is disposed on the semiconductor layer 4. An opening OP is formed in the first insulating film 3a. In this embodiment, the semiconductor layer 4 is exposed from the first insulating film 3a at the opening OP. Therefore, electromagnetic waves irradiate the semiconductor layer 4 through the opening OP. The shape of the first insulating film 3a can be determined as long as the opening OP is provided. The shape of the opening OP can be determined as long as the semiconductor layer 4 is exposed from the first insulating film 3a. It is sufficient that at least one of the two-dimensional material layer 1 and the semiconductor layer 4 is exposed from the opening OP. Therefore, it is sufficient that electromagnetic waves irradiate both the two-dimensional material layer 1 and the semiconductor layer 4 through the opening OP.

[0069] like Figure 2 As shown, the shape of the first insulating film 3a can be a shape surrounded by the opening OP. Additionally, as... Figure 3 As shown, the shape of the first insulating film 3a can be the shape that surrounds the opening OP. For example... Figure 4 As shown, the second insulating film 3b can be the shape that covers the entire two-dimensional material layer 1.

[0070] like Figure 1 As shown, the two-dimensional material layer 1 is electrically connected to the semiconductor layer 4 at the opening OP. The two-dimensional material layer 1 extends from the opening OP to the first insulating film 3a. The two-dimensional material layer 1 contains any material selected from the group consisting of graphene, transition metal dichalcogenide (TMD), black phosphorus, silicene (a two-dimensional honeycomb structure based on silicon atoms), graphene nanoribbon, and borophene. In this embodiment, the material of the two-dimensional material layer 1 includes graphene, which will be described later. The material of the two-dimensional material layer 1 is preferably a material that generates surface plasmon resonance.

[0071] The two-dimensional material layer 1 includes a first portion 1a, a second portion 1b, and a third portion 1c. In this embodiment, the first portion 1a is directly connected to the semiconductor layer 4. The first portion 1a is disposed within the opening OP. Electromagnetic waves irradiating the electromagnetic wave detector 100 pass through the first portion 1a and enter the semiconductor layer 4. In this embodiment, the second portion 1b is disposed on the first insulating film 3a. As will be explained later, a gap may be provided between the second portion 1b and the first insulating film 3a. The third portion 1c is electrically connected to the first electrode 2a. Figure 1 In the middle, part 3 1c is disposed on the first electrode 2a, and can be disposed as appropriate as long as it is electrically connected to the first electrode 2a.

[0072] The first electrode 2a is disposed on the first insulating film 3a. The first electrode 2a is connected to the semiconductor layer 4 through the first insulating film 3a. The first electrode 2a is electrically connected to the two-dimensional material layer 1. The first electrode 2a can be directly connected to the two-dimensional material layer 1.

[0073] The second electrode 2b is electrically connected to the semiconductor layer 4. The second electrode 2b can be directly connected to the semiconductor layer 4. The electromagnetic wave detector 100 is configured to change the voltage difference between the first electrode 2a and the second electrode 2b. Therefore, the electromagnetic wave detector 100 is configured such that a bias voltage V1 is applied to the two-dimensional material layer 1, the first insulating film 3a, and the semiconductor layer 4 disposed between the first electrode 2a and the second electrode 2b.

[0074] The second insulating film 3b is in contact with the two-dimensional material layer 1. The second insulating film 3b can be directly connected to the two-dimensional material layer 1. In this embodiment, the second insulating film 3b and the semiconductor layer 4 sandwich the two-dimensional material layer 1. The second insulating film 3b is disposed on the two-dimensional material layer 1.

[0075] The control electrode 2c is connected to the two-dimensional material layer 1 through the second insulating film 3b. In this embodiment, the control electrode 2c and the two-dimensional material layer 1 are sandwiched by the second insulating film 3b. The control electrode 2c is disposed on the second insulating film 3b. The electromagnetic wave detector 100 is configured to apply a voltage to the two-dimensional material layer 1 using the control electrode 2c. Specifically, the electromagnetic wave detector 100 is configured to change the Fermi level of the two-dimensional material layer 1 by applying a voltage to the two-dimensional material layer 1 using the control electrode 2c.

[0076] In this embodiment, the control electrode 2c includes a plurality of control electrode portions 2c0. The plurality of control electrode portions 2c0 includes a first control electrode portion 2c1. The first control electrode portion 2c1 is connected to the first portion 1a via a second insulating film 3b. When the control electrode 2c includes a plurality of control electrode portions 2c0, the second insulating film 3b may include a plurality of second insulating film portions 3b0. Each control electrode portion of the plurality of control electrode portions 2c0 is connected to the semiconductor layer 4 via a respective second insulating film portion of the plurality of second insulating film portions 3b0.

[0077] As long as the control electrode 2c is connected to the two-dimensional material layer 1 through the second insulating film 3b, the number and position of the multiple control electrode portions 2c0 can be determined as appropriate. Furthermore, as... Figure 5 As shown, the control electrode 2c can be a single electrode. Even when the control electrode 2c is a single electrode, the Fermi level of the two-dimensional material layer 1 is controlled by voltage.

[0078] like Figure 1 As shown, the semiconductor layer 4 includes a first surface 4a and a second surface 4b. The second surface 4b is opposite to the first surface 4a. A two-dimensional material layer 1 and a first insulating film 3a are disposed on the first surface 4a. Electromagnetic waves irradiate the first surface 4a side of the semiconductor layer 4. A second electrode 2b may be disposed on the second surface 4b.

[0079] Semiconductor layer 4 is sensitive to the detection wavelength. In this embodiment, the detection wavelength is the range of wavelengths of the electromagnetic wave that is the object of detection by the electromagnetic wave detector 100. The detection wavelength is predetermined. Semiconductor layer 4 is configured such that photocarriers are generated in semiconductor layer 4 when irradiated by electromagnetic waves having the detection wavelength. In this embodiment, the phenomenon of photocarrier generation due to irradiation by electromagnetic waves is called photoelectric conversion. The semiconductor material constituting semiconductor layer 4 can be determined as appropriate according to the detection wavelength.

[0080] The Fermi level of semiconductor layer 4 differs from that of two-dimensional material layer 1. The Fermi level of two-dimensional material layer 1 is the energy required to form a Schottky barrier between it and semiconductor layer 4. Therefore, a Schottky barrier is formed between two-dimensional material layer 1 and semiconductor layer 4. Consequently, two-dimensional material layer 1 and semiconductor layer 4 are configured to function as a diode using the Schottky barrier.

[0081] The electromagnetic wave detector 100 also includes a first power supply circuit (not shown) and a second power supply circuit (not shown). The electromagnetic wave detector 100 may also include a galvanometer (not shown). The first power supply circuit is configured to apply a bias voltage V1 to the first insulating film 3a and the semiconductor layer 4 via the first electrode 2a and the second electrode 2b. The electromagnetic wave detector 100 is configured to utilize the first power supply circuit to change the voltage difference between the first electrode 2a and the second electrode 2b.

[0082] The second power supply circuit is configured to apply a control voltage V2 to the two-dimensional material layer 1 via the control electrode 2c. The control voltage V2 is a voltage used to control the Fermi level of the two-dimensional material layer 1. The electromagnetic wave detector 100 is configured to change the Fermi level of the two-dimensional material layer 1 by applying a voltage to the two-dimensional material layer 1 via the control electrode 2c using the second power supply circuit.

[0083] When the control electrode 2c includes multiple control electrode sections 2c0, the electromagnetic wave detector 100 may include multiple second power supply circuits. Each of the multiple second power supply circuits may be connected to each control electrode section of the multiple control electrode sections 2c0. For example, each of the three second power supply circuits may apply different control voltages V2, V3, and V4 to each control electrode section of the three control electrode sections 2c0.

[0084] When a control voltage V2 is applied to the two-dimensional material layer 1, the Fermi level of the two-dimensional material layer 1 changes. Thus, even assuming that the Fermi level of the two-dimensional material layer 1 before the change is an energy that cannot form a Schottky barrier with the semiconductor layer 4, the Fermi level of the two-dimensional material layer 1 becomes an energy that can form a Schottky barrier with the semiconductor layer 4.

[0085] The ammeter is electrically connected to the first power supply circuit. The ammeter is configured to detect the current flowing through the two-dimensional material layer 1 between the first electrode 2a and the second electrode 2b.

[0086] <Regarding the Schottky barrier set between the two-dimensional material layer 1 and the semiconductor layer 4>

[0087] Next, use Figure 6 and Figure 7 This is to illustrate the Schottky barrier formed between the two-dimensional material layer 1 and the semiconductor layer 4.

[0088] Figure 6 and Figure 7 The band structure diagram is shown when the material of the two-dimensional material layer 1 is graphene and the semiconductor layer 4 is indium antimonide (InSb). Figure 6 To form the band structure under the Schottky barrier. Figure 7 This is the energy band diagram before the Schottky barrier is formed. Semiconductor layer 4 has p-type conductivity. The photocarriers are electrons. φ B For the Schottky barrier. E FG E represents the Fermi level of the two-dimensional material layer 1. FS E represents the Fermi level of semiconductor layer 4. C This is the conduction band of semiconductor layer 4. E V This is the valence band of semiconductor layer 4.

[0089] exist Figure 6 In this structure, the Fermi level of the two-dimensional material layer 1 is greater than the lower limit of the valence band of the semiconductor layer 4. Therefore, a Schottky barrier is formed between the two-dimensional material layer 1 and the semiconductor layer 4. Consequently, diode characteristics are generated between the two-dimensional material layer 1 and the semiconductor layer 4.

[0090] Furthermore, since the electromagnetic wave detector 100 is configured to change the voltage difference between the first electrode 2a and the second electrode 2b, a voltage is applied to the two-dimensional material layer 1 and the semiconductor layer 4 so that the photocarriers have the energy to overcome the Schottky barrier. As a result, the photocarriers cross the Schottky barrier from the two-dimensional material layer 1 and reach the semiconductor layer 4.

[0091] Assuming in such Figure 7When the Fermi level of the two-dimensional material layer 1 is lower than the lower limit of the valence band of the semiconductor layer 4, no Schottky barrier is formed between the two-dimensional material layer 1 and the semiconductor layer 4. Therefore, no diode characteristics are generated between the two-dimensional material layer 1 and the semiconductor layer 4. When no diode characteristics are generated between the two-dimensional material layer 1 and the semiconductor layer 4, the dark current flowing through the two-dimensional material layer 1 increases. Therefore, even if a large detection signal is obtained by utilizing the photo-gating effect (described later), the signal-to-noise ratio deteriorates.

[0092] Furthermore, assuming a small Schottky barrier, the operation of the electromagnetic wave detector 100 becomes unstable because the ratio of the change in dark current to the bias voltage V1 increases. That is, even with a slight change in the bias voltage V1, the dark current increases, thus deteriorating the signal-to-noise ratio.

[0093] also, Figure 6 and Figure 7 The diagram shows the energy band structure when the photocarrier is an electron and the conductivity type of semiconductor layer 4 is p-type, but the photocarrier and conductivity type are not limited to this. That is, as long as a Schottky barrier is formed between the two-dimensional material layer 1 and the semiconductor layer 4, the photocarrier can be either an electron or a hole. Furthermore, as long as a Schottky barrier is formed between the two-dimensional material layer 1 and the semiconductor layer 4, the conductivity type of semiconductor layer 4 can be either n-type or p-type.

[0094] Next, the structures of the two-dimensional material layer 1, the first electrode 2a, the second electrode 2b, the control electrode 2c, the first insulating film 3a, and the semiconductor layer 4 of the electromagnetic wave detector 100 of Embodiment 1 will be described in detail.

[0095] <Structure of Two-Dimensional Material Layer 1>

[0096] The two-dimensional material layer 1 is, for example, a single layer of graphene. A single layer of graphene is a single atomic layer of a two-dimensional carbon crystal. The thickness of the single layer of graphene is, for example, 0.34 nm, equivalent to one carbon atom. Furthermore, the graphene has multiple carbon atoms arranged in each of a plurality of chains arranged in a hexagonal shape. The absorption rate of graphene is as low as 2.3%. Specifically, the absorption rate of graphene for white light is 2.3%. Moreover, in this embodiment, the white light is light uniformly mixed with light having visible wavelengths.

[0097] The two-dimensional material layer 1 can be a multilayer graphene composed of multiple graphene layers stacked together. The orientations of the lattice vectors of the hexagonal lattices of the individual graphene layers in the multilayer graphene can be consistent or different. Alternatively, the orientations of the lattice vectors of the hexagonal lattices of the individual graphene layers in the multilayer graphene can be completely consistent.

[0098] For example, a band gap is formed in the two-dimensional material layer 1 by stacking two or more graphene layers. That is, the size of the band gap can be adjusted by changing the number of stacked graphene layers. As a result, the two-dimensional material layer 1 can have a wavelength selectivity effect that selects the electromagnetic wave (detection wavelength) that is the object of photoelectric conversion. In addition, for example, when the number of graphene layers in the multilayer graphene increases, the mobility in the channel region decreases. On the other hand, when the number of graphene layers in the multilayer graphene increases, the influence of carrier scattering from the substrate is suppressed, and thus the noise of the electromagnetic wave detector 100 is reduced. Therefore, in the electromagnetic wave detector 100 having a two-dimensional material layer 1 using multilayer graphene, light absorption is increased, and thus the detection sensitivity of electromagnetic waves is improved.

[0099] The two-dimensional material layer 1 includes a region that functions as a channel region and a region that functions as a source / drain layer. In this embodiment, part 1a and part 1c are regions that function as source / drain regions. Part 2b is a region that functions as a channel region.

[0100] The material of the two-dimensional material layer 1 can be the same or different in the region where it functions as a channel region and in the region where it functions as a source / drain layer.

[0101] Photocarriers are doped from the first electrode 2a into the two-dimensional material layer 1 through contact between the third portion 1c of the two-dimensional material layer 1 and the first electrode 2a. For example, when the two-dimensional material layer 1 is graphene and the first electrode 2a is gold (Au), the photocarriers are holes. Due to the difference between the work function of graphene and the work function of gold (Au), holes are doped into the third portion 1c that is in contact with the first electrode 2a. When the electromagnetic wave detector 100 is driven in the electron conduction state with holes doped in the third portion 1c, the mobility of electrons flowing in the channel decreases due to the influence of holes. Therefore, the contact resistance between the two-dimensional material layer 1 and the first electrode 2a increases. In particular, when all regions of the two-dimensional material layer 1 are formed of monolayer graphene, the amount of carriers injected into the two-dimensional material layer 1 from the first electrode 2a (doping amount) is large. Therefore, the field-effect mobility of the electromagnetic wave detector 100 is significantly reduced. Therefore, when all regions of the two-dimensional material layer 1 are formed by a single layer of graphene, the performance of the electromagnetic wave detector 100 is reduced.

[0102] The amount of charge carriers doped from the first electrode 2a into the multilayer graphene is less than the amount of charge carriers doped from the first electrode 2a into the monolayer graphene. Therefore, by forming the source / drain regions (part 1a and part 1c) that are easily doped with charge carriers from the multilayer graphene, the increase in contact resistance between the two-dimensional material layer 1 and the first electrode 2a can be suppressed. As a result, the performance of the electromagnetic wave detector 100 can be improved because the decrease in the field-effect mobility of the electromagnetic wave detector 100 can be suppressed.

[0103] Based on the above, it is preferable to use multilayer graphene as the material for the source / drain regions (Part 1a and Part 3c). Alternatively, monolayer graphene is used in the channel region (Part 2b).

[0104] Alternatively, the two-dimensional material layer 1 can be undoped graphene. The two-dimensional material layer 1 can also be graphene doped with p-type or n-type impurities.

[0105] Alternatively, graphene nanoribbons (graphene nanoribbons) can be used as the two-dimensional material layer 1. The two-dimensional material layer 1 can be a single graphene nanoribbon. The structure of the two-dimensional material layer 1 can be a structure composed of multiple stacked graphene nanoribbons. The structure of the two-dimensional material layer 1 can be a structure in which graphene nanoribbons are periodically arranged in a plane. When the structure of the two-dimensional material layer 1 is a periodically arranged graphene nanoribbon, the sensitivity of the electromagnetic wave detector 100 is improved due to plasmon resonance occurring in the graphene nanoribbons. The structure of periodically arranged graphene nanoribbons is sometimes also referred to as a graphene metamaterial.

[0106] A protective film (not shown) can be formed on the two-dimensional material layer 1. The protective film (not shown) is configured to cover the two-dimensional material layer 1, the first electrode 2a, the first insulating film 3a, and the semiconductor layer 4. The protective film is, for example, an insulating film made of silicon oxide (SiO).

[0107] The protective film can be an insulating film such as an oxide or nitride. Examples of protective films include aluminum oxide (Al₂O₃) and hafnium oxide (HfO₂). Boron nitride (BN) can also be used.

[0108] <Structure of the first electrode 2a, the second electrode 2b, and the control electrode 2c>

[0109] The materials of the first electrode 2a, the second electrode 2b, and the control electrode 2c can be any material as long as they are conductive. The materials of the first electrode 2a, the second electrode 2b, and the control electrode 2c can include at least any material selected from, for example, gold (Au), silver (Ag), copper (Cu), aluminum (Al), nickel (Ni), chromium (Cr), and palladium (Pd). Adhesive layers (not shown) can be provided between the first electrode 2a and the first insulating film 3a, between the second electrode 2b and the semiconductor layer 4, and between the control electrode 2c and the second insulating film 3b. These adhesive layers are formed to improve adhesion. The materials of the adhesive layers include, for example, metallic materials such as chromium (Cr) or titanium (Ti).

[0110] <Structure of the first insulating film 3a and the second insulating film 3b>

[0111] The first insulating film 3a and the second insulating film 3b are, for example, silicon oxide (SiN) insulating films. The materials of the first insulating film 3a and the second insulating film 3b can be, for example, tetraethyl orthosilicate (Si(OC2H5)4), silicon nitride (Si3N4), hafnium oxide (HfO2), aluminum oxide (Al2O3), nickel oxide (NiO), boron nitride (BN), or siloxane polymer materials. For example, the atomic arrangement of boron nitride (BN) is similar to that of graphene. Therefore, when boron nitride (BN) is in contact with the two-dimensional material layer 1 composed of graphene, the decrease in electron mobility of the two-dimensional material layer 1 is suppressed. Therefore, boron nitride (BN) is suitable as an insulating film for a substrate film disposed beneath the two-dimensional material layer 1.

[0112] There are no particular restrictions on the thickness of the first insulating film 3a and the second insulating film 3b, provided that the two-dimensional material layer 1, the first electrode 2a and the second electrode 2b are electrically insulated relative to the semiconductor layer 4 and no tunneling current is generated between the two-dimensional material layer 1, the first electrode 2a and the second electrode 2b and the semiconductor layer 4.

[0113] Furthermore, the thinner the first insulating film 3a, the greater the degree of electric field change in the two-dimensional material layer 1 caused by photocarriers generated at the interface between the first insulating film 3a and the semiconductor layer 4. Similarly, the thinner the second insulating film 3b, the greater the degree of electric field change in the two-dimensional material layer 1 caused by photocarriers generated at the interface between the second insulating film 3b and the semiconductor layer 4. Therefore, it is preferable that the thicknesses of the first insulating film 3a and the second insulating film 3b are as thin as possible. In this embodiment, the change in the electric field of the two-dimensional material layer 1 caused by photocarriers generated at the interface between the insulating films (first insulating film 3a and second insulating film 3b) and the semiconductor layer 4 is referred to as the optical gating effect. The detailed generation process of the optical gating effect will be described later.

[0114] <Semiconductor layer 4>

[0115] The semiconductor layer 4 can be made of materials such as silicon (Si), germanium (Ge), compound semiconductors (III-V or II-V group semiconductors), mercury cadmium telluride (HgCdTe), iridium antimonide (InSb), lead selenide (PbSe), lead sulfide (PbS), cadmium sulfide (CdS), gallium nitride (GaN), silicon carbide (SiC), gallium phosphide (GaP), gallium arsenide (InGaAs), or indium arsenide (InAs). The semiconductor layer 4 can be a substrate including quantum wells or quantum dots. The semiconductor layer 4 can be a type II superlattice. The semiconductor layer 4 can be a single material of the above-mentioned materials or a combination of the above-mentioned materials. The materials of the semiconductor layer 4 have different detection wavelengths. Therefore, if the semiconductor layer 4 is a combination of the above-mentioned semiconductor materials, multi-wavelength detection can be performed using the electromagnetic wave detector 100 equipped with the semiconductor layer 4.

[0116] Preferably, the semiconductor layer 4 is doped with impurities to make its resistivity 100 Ω·cm or less. A pn ​​junction can be formed inside the semiconductor layer 4, as will be explained later. When a pn junction is formed, the readout speed of photocarriers generated at the pn junction interface is improved due to the high concentration of doping in the semiconductor layer 4, thus improving the response speed of the electromagnetic wave detector 100.

[0117] <Manufacturing Method of Electromagnetic Wave Detector 100>

[0118] Next, use Figure 1 The manufacturing method of the electromagnetic wave detector 100 according to Embodiment 1 will be described.

[0119] The manufacturing method of the electromagnetic wave detector 100 includes a preparation step, a first insulating film formation step, a resist removal step, a first electrode formation step, an opening formation step, a two-dimensional material layer formation step, a second insulating film formation step, and a control electrode formation step. The preparation step, the first insulating film formation step, the resist removal step, the first electrode formation step, the opening formation step, the two-dimensional material layer formation step, the second insulating film formation step, and the control electrode formation step are performed sequentially.

[0120] First, a preparation process is implemented. In the preparation process, such as... Figure 1 As shown, a flat semiconductor substrate containing silicon (Si) or the like is prepared as semiconductor layer 4. The material of the semiconductor substrate is sensitive to a predetermined detection wavelength.

[0121] Next, the second electrode formation process is performed. In the second electrode formation process, a photoresist is formed as a protective film on the first surface 4a of the semiconductor layer 4. The second electrode 2b is deposited on the second surface 4b of the semiconductor layer 4. Before the second electrode 2b is deposited, an adhesion layer (not shown) can be formed on the area of ​​the second electrode 2b on the second surface 4b of the semiconductor layer 4 where the second electrode 2b is to be deposited.

[0122] Next, a resist removal process is performed. In the resist removal process, the resist is removed from the first surface 4a of the semiconductor layer 4.

[0123] Next, the first insulating film formation process is performed. In the first insulating film formation process, a first insulating film 3a is formed on the first surface 4a of the semiconductor layer 4. For example, when the material of the semiconductor layer 4 is silicon (Si), the first insulating film 3a can be thermally oxidized silicon oxide (SiO2). In addition, the film formation method of the first insulating film 3a can be CVD (Chemical Vapor Deposition) or sputtering.

[0124] Next, the first electrode forming process is performed. In the first electrode forming process, the first electrode 2a is formed on the first insulating film 3a. Before forming the first electrode, an adhesion layer may be formed in the area of ​​the first insulating film 3a where the first electrode 2a is to be formed.

[0125] One method for forming the first electrode 2a is as follows: First, a photoresist mask is formed on the upper surface of the first insulating film 3a using photochemical engraving or electron beam lithography. An opening region is formed in the area of ​​the photoresist mask where the first electrode 2a is to be formed. Then, a film of a metal or the like that to become the first electrode 2a is formed on the photoresist mask. This film is formed using a vapor deposition or sputtering method. At this time, the film is formed to extend from the interior of the opening region of the photoresist mask to the upper surface of the photoresist mask. Then, the photoresist mask and a portion of the film are removed together. The remaining portion of the film disposed in the opening region of the photoresist mask remains on the surface of the first insulating film 3a, becoming the first electrode 2a. This method is commonly referred to as a lift-off method.

[0126] Other methods can be used as a method for forming the first electrode 2a. For example, on the surface of the first insulating film 3a, a film such as a metal film to be the first electrode 2a is first formed. Then, a photoresist mask is formed on the film using photolithography. The photoresist mask is formed to cover the area where the first electrode 2a is formed, while no photoresist mask is formed in the area outside the area where the first electrode 2a is formed. Then, the film is partially removed using wet etching or dry etching, with the photoresist mask as a mask. As a result, a portion of the film remains under the photoresist mask. This portion of the film becomes the first electrode 2a. Then, the photoresist mask is removed. The first electrode 2a can be formed in this way.

[0127] Next, the opening formation process is performed. Alternatively, the opening formation process can be performed before the first electrode formation process. In the opening formation process, an opening OP is formed on the first insulating film. Specifically, a resist mask (not shown) is formed on the first insulating film 3a using photolithography or electron beam lithography. An opening region is formed in the area of ​​the resist mask where the opening OP of the first insulating film 3a is to be formed. Then, the first insulating film 3a is etched using the resist mask as an etching mask. As the etching method, any method can be selected from the wet etching and dry etching methods described above. After etching, the resist mask is removed. The opening OP is formed on the first insulating film 3a in this way.

[0128] Next, a two-dimensional material layer formation process is performed. In this process, the two-dimensional material layer 1 is formed such that the first electrode 2a, the first insulating film 3a, and the semiconductor layer 4 exposed inside the opening OP are covered by the two-dimensional material layer 1. There are no particular limitations on the method for forming the two-dimensional material layer 1. The two-dimensional material layer 1 can be formed, for example, by epitaxial growth or by screen printing. Alternatively, the two-dimensional material layer 1 can be formed by transferring and bonding a two-dimensional material film previously formed using CVD. The two-dimensional material layer 1 can also be formed by transferring and bonding a film-like two-dimensional material film peeled off using mechanical peeling or the like.

[0129] After forming a two-dimensional material layer 1, a photoresist mask is formed on the two-dimensional material layer 1 using photolithography or the like. The photoresist mask is formed to cover the area where the two-dimensional material layer 1 is to be formed, exposing the remaining areas. Then, the two-dimensional material layer 1 is etched using the photoresist mask as an etching mask. The etching method is, for example, dry etching using oxygen plasma. Afterward, the photoresist mask is removed. Thus, a two-dimensional material layer 1 is formed. Figure 1 The two-dimensional material layer 1 is shown.

[0130] Next, the second insulating film formation process is performed. In the second insulating film formation process, an insulating film is formed on the two-dimensional material layer 1. The method for forming the second insulating film 3b is, for example, electron beam evaporation, CVD, sputtering, etc. Preferably, the method for forming the second insulating film 3b is a method that does not damage the two-dimensional material layer 1. The shape of the second insulating film 3b is processed by photolithography or the like. Furthermore, at any point in time during the second insulating film formation process, the shape of the second insulating film 3b can be as follows: Figure 1 The shape of the area where the control electrode 2c contacts the second insulating film 3b is the same as that of the control electrode 2c. Furthermore, at the time of the second insulating film formation process, the shape of the second insulating film 3b can be processed to a size large enough that the control electrode 2c does not directly contact the two-dimensional material layer 1. Alternatively, the shape of the second insulating film 3b can be processed after the control electrode 2c is formed in the control electrode formation process. Similar to the opening OP formation process described above, after forming a resist mask using photolithography or EB lithography, the second insulating film 3b is processed using dry etching or the like.

[0131] Next, a control electrode forming process is performed. In this process, a control electrode 2c is formed on the second insulating film 3b. The method for forming the control electrode 2c is the same as the method for forming the first electrode 2a in the first electrode forming process.

[0132] The electromagnetic wave detector 100 of this embodiment is manufactured according to the above.

[0133] Furthermore, in the above manufacturing method, the two-dimensional material layer 1 is formed on the first electrode 2a. However, it is also possible to form the first electrode 2a on a portion of the two-dimensional material layer 1 after the two-dimensional material layer 1 is formed on the first insulating film 3a. However, when forming the first electrode 2a, care should be taken to avoid damage to the two-dimensional material layer 1 due to the formation process of the first electrode 2a.

[0134] <Working Principle of Electromagnetic Wave Detector 100>

[0135] Next, use Figure 1 The working principle of the electromagnetic wave detector 100 in Embodiment 1 will be explained.

[0136] like Figure 1As shown, a first power supply circuit (not shown) is electrically connected between the first electrode 2a and the second electrode 2b. A bias voltage V1 is applied between the first electrode 2a and the second electrode 2b. This forms a current path inside the electromagnetic wave detector 100, consisting of the first electrode 2a, the two-dimensional material layer 1, the semiconductor layer 4, and the second electrode 2b connected in series. A current I flows through the two-dimensional material layer 1. The current I flowing through the two-dimensional material layer 1 is measured using a galvanometer (not shown) connected to the first power supply circuit. This allows the electromagnetic wave detector 100 to enter a state capable of detecting electromagnetic waves. Furthermore, the polarity of the voltage is selected based on the conductivity type (doping type) of the semiconductor layer 4. If the conductivity type of the semiconductor layer 4 is p-type, a positive voltage is applied to the first electrode 2a. If the conductivity type of the semiconductor layer 4 is n-type, a negative voltage is applied to the first electrode 2a.

[0137] When an electromagnetic wave of a wavelength sensitive to semiconductor layer 4 (an electromagnetic wave with a detection wavelength) irradiates semiconductor layer 4, photocarriers are generated inside semiconductor layer 4. The two-dimensional material layer 1 and semiconductor layer 4 function as diodes. Therefore, the photocarriers generated in the region of semiconductor layer 4 facing the opening OP are injected into the first portion 1a of the two-dimensional material layer 1. The magnitude of the current I changes as the photocarriers pass through the first portion 1a. In this embodiment, the current component whose magnitude changes due to the irradiated electromagnetic wave is called the photocurrent.

[0138] Furthermore, the aforementioned optical gating effect is caused by the following process. Since the semiconductor layer 4 and the first insulating film 3a function as diodes, a depletion layer is formed at the interface between the semiconductor layer 4 and the first insulating film 3a by applying a voltage to the semiconductor layer 4. When an electromagnetic wave with a detection wavelength is irradiated onto the semiconductor layer 4, photocarriers are also generated within the depletion layer. The photocarriers generated in the depletion layer exert a field effect on the third portion 1c of the two-dimensional material layer 1 via the first insulating film 3a. As a result, the resistance of the two-dimensional material layer 1 changes, and therefore the current I flowing through the two-dimensional material layer 1 changes. That is, a field effect is generated due to the electromagnetic wave irradiating the semiconductor layer 4. The electrical characteristics of the two-dimensional material layer 1 change due to the field effect.

[0139] Changes in current I are detected via a first electrode 2a electrically connected to the two-dimensional material layer 1. More specifically, changes in current I are detected using a galvanometer (not shown), which is connected to a first power supply circuit (not shown) electrically connected to a first power supply. Thus, the electromagnetic wave detector 100 detects electromagnetic waves irradiating it.

[0140] Here, the electromagnetic wave detector 100 of this embodiment is not limited to the structure described above that uses a galvanometer (not shown) to detect current changes in the two-dimensional material layer 1. For example, a constant current can be allowed to flow between the first electrode 2a and the second electrode 2b, and a voltmeter (not shown) can be used to detect changes in the voltage V between the first electrode 2a and the second electrode 2b (that is, changes in the voltage value in the two-dimensional material layer 1).

[0141] Alternatively, the aforementioned electromagnetic wave detector 100 can be configured as a first electromagnetic wave detector, and a second electromagnetic wave detector having the same structure as the first electromagnetic wave detector can also be configured. The first electromagnetic wave detector is disposed in a space irradiated by electromagnetic waves. The second electromagnetic wave detector is disposed in a space where electromagnetic waves are shielded. Detection can be performed by detecting the difference between the current of the first electromagnetic wave detector and the current of the second electromagnetic wave detector. Detection can also be performed by detecting the difference between the voltage of the first electromagnetic wave detector and the voltage of the second electromagnetic wave detector.

[0142] <Effects>

[0143] Next, the effects of this implementation method will be explained.

[0144] According to the electromagnetic wave detector 100 of Embodiment 1, such as Figure 1 As shown, the electromagnetic wave detector 100 includes a control electrode 2c. Therefore, the Fermi level of the two-dimensional material layer 1 can be changed by applying a voltage (control voltage V2) to the control electrode 2c.

[0145] More specifically, the Fermi level of the two-dimensional material layer 1 is unstable. Therefore, the Fermi level of the two-dimensional material layer 1 changes with variations in the fabrication and operating environment of the electromagnetic wave detector 100. Variations caused by the operating environment include, for example, doping of the insulating film and electrodes, and aging. Consequently, the Fermi level of the two-dimensional material layer 1 may become an energy that prevents the formation of a Schottky barrier between the two-dimensional material layer 1 and the semiconductor layer 4. In this case, the electromagnetic wave detector 100 malfunctions. Furthermore, even if the Fermi level of the two-dimensional material layer 1 was an energy capable of forming a Schottky barrier at the time the electromagnetic wave detector 100 was manufactured, it may become an energy that prevents the formation of a Schottky barrier. Additionally, in a Schottky-type electromagnetic wave detector where the two-dimensional material layer is formed on a semiconductor layer, the Fermi level of the two-dimensional material layer remains unchanged after the formation of the two-dimensional material layer. Therefore, when the Fermi level of the two-dimensional material layer 1 is not an energy capable of forming a Schottky barrier, a Schottky barrier cannot be formed. Based on the above, it is necessary to change the Fermi level of the two-dimensional material layer 1 after the electromagnetic wave detector 100 is manufactured.

[0146] The electromagnetic wave detector 100 of this embodiment includes a control electrode 2c. Therefore, even after the electromagnetic wave detector 100 is manufactured, the Fermi level of the two-dimensional material layer 1 can be changed.

[0147] like Figure 1 As shown, the electromagnetic wave detector 100 includes a control electrode 2c. Therefore, the Fermi level of the two-dimensional material layer 1 can be converted to the energy required to form a Schottky barrier between the two-dimensional material layer 1 and the semiconductor layer 4. Thus, a Schottky barrier can be formed between the two-dimensional material layer 1 and the semiconductor layer 4.

[0148] This allows for a change in the Schottky barrier, which in turn allows for a change in the cutoff wavelength. The cutoff wavelength is within the wavelength range that the electromagnetic wave detector 100 can respond to. Therefore, the cutoff wavelength can be controlled by applying a control voltage V2 to the two-dimensional material layer 1.

[0149] like Figure 1 As shown, the control electrode 2c is sandwiched between the two-dimensional material layer 1 and the second insulating film 3b. Therefore, the control electrode 2c can be formed after the two-dimensional material layer 1 is formed. Thus, compared to the case where the two-dimensional material layer 1 is formed on the control electrode 2c after the control electrode 2c is formed, the unevenness of the two-dimensional material layer 1 can be reduced. That is, the two-dimensional material layer 1 can be made flat. Therefore, the performance of the two-dimensional material layer 1 is improved. In addition, the first electrode 2a, the second electrode 2b, and the control electrode 2c can be formed simultaneously after the two-dimensional material layer 1 is formed. Therefore, the manufacturing steps of the electromagnetic wave detector 100 can be reduced.

[0150] like Figure 1 As shown, the electromagnetic wave detector 100 is configured to change the voltage difference between the first electrode 2a and the second electrode 2b. Therefore, a bias voltage V1 can be applied to the two-dimensional material layer 1 and the semiconductor layer 4 to allow photocarriers to cross the Schottky barrier. Consequently, photocarriers can be injected from the semiconductor layer 4 into the two-dimensional material layer 1. Therefore, the detection sensitivity of the electromagnetic wave detector 100 can be improved.

[0151] like Figure 1 As shown, the electromagnetic wave detector 100 is configured to change the Fermi level of the two-dimensional material layer 1 by applying a voltage to the control electrode 2c. Therefore, even after the electromagnetic wave detector 100 is manufactured, the Fermi level of the two-dimensional material layer 1 can be changed.

[0152] like Figure 1As shown, the control electrode 2c includes multiple control electrode sections 2c0. Therefore, by applying different control voltages to each of the multiple control electrode sections 2c0, a potential gradient can be formed within the two-dimensional material layer 1. An internal electric field is formed in the two-dimensional material layer 1 using this potential gradient. Consequently, the extraction efficiency of photocarriers generated by photoelectric conversion in the two-dimensional material layer 1 when irradiated with electromagnetic waves can be improved. In this embodiment, the extraction efficiency is the efficiency of photocarriers moving from the semiconductor layer 4 to the two-dimensional material layer 1. This allows for an increase in the photocurrent flowing through the two-dimensional material layer 1. Consequently, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0153] The two-dimensional material layer 1 includes any material selected from the group consisting of graphene, transition metal dichalcogenides, black phosphorus, silicene, graphene nanoribbons, and borophene. Therefore, the effects of this embodiment can be reliably obtained.

[0154] When the material of the two-dimensional material layer 1 is monolayer graphene, the thickness of the two-dimensional material layer 1 is only one atomic layer, thus it is thin. Furthermore, compared to conventional semiconductor materials, monolayer graphene has a higher carrier mobility. Therefore, in the two-dimensional material layer 1, compared to conventional semiconductor materials, a small potential change results in a large current change. For example, the current change caused by a potential change applied to the two-dimensional material layer 1 due to a change in the electric field in the semiconductor layer 4 is greater than the current change in a conventional semiconductor. Specifically, based on the electron mobility and thickness of the two-dimensional material layer 1, the aforementioned current change in the two-dimensional material layer 1 is approximately several hundred to several thousand times greater than the current change in a conventional semiconductor. Therefore, the electromagnetic wave detector 100 according to this embodiment can perform electromagnetic wave detection with higher sensitivity compared to electromagnetic wave detectors that only detect photocarriers generated in the semiconductor layer 4.

[0155] Therefore, according to this embodiment, the electromagnetic wave detector 100 generates not only the photocurrent generated in the semiconductor layer 4 due to light irradiation and the current caused by the photogating effect, but also the photocurrent caused by the photoelectric conversion effect of the two-dimensional material layer 1. In addition to detecting the current generated in the semiconductor layer 4 due to electromagnetic wave incidence and the current caused by the photogating effect, the electromagnetic wave detector 100 can also detect the photocurrent caused by the inherent photoelectric conversion effect of the two-dimensional material layer 1.

[0156] like Figure 1As shown, the two-dimensional material layer 1 is electrically connected to the semiconductor layer 4 at the opening OP. Therefore, the two-dimensional material layer 1 and the semiconductor layer 4 function as diodes. Thus, by applying a reverse bias to the two-dimensional material layer 1 and the semiconductor layer 4, the current I in the unlit state can be made zero. That is, by applying a reverse bias, the electromagnetic wave detector 100 can be turned off. As a result, since dark current flowing through the two-dimensional material layer 1 can be suppressed, the sensitivity of the electromagnetic wave detector 100 can be improved. In addition, in the state of being illuminated by light, only the current caused by photocarriers injected into the two-dimensional material layer 1 is detected as the current I flowing through the electromagnetic wave detector 100. Furthermore, the current caused by photocarriers injected into the two-dimensional material layer 1 is detected after the current magnitude changes due to the aforementioned photogating effect.

[0157] like Figure 1 As shown, the two-dimensional material layer 1 extends from the opening OP to the first insulating film 3a. Therefore, the two-dimensional material layer 1 is connected to the semiconductor layer 4 through the first insulating film 3a. Consequently, an optical gating effect occurs in the two-dimensional material layer 1, thus changing its voltage. This voltage change in the two-dimensional material layer 1 is approximated as the application of a gate voltage to the two-dimensional material layer 1. This allows modulation of the conductivity of the two-dimensional material layer 1. Therefore, the photocurrent injected from the semiconductor layer 4 into the two-dimensional material layer 1 can be amplified.

[0158] The optical gating effect does not directly enhance the quantum efficiency of photoelectric conversion materials, but rather increases the current change caused by the incident electromagnetic wave. Therefore, the quantum efficiency calculated based on the differential current caused by the incident electromagnetic wave exceeds 100%, and under optimized conditions, the equivalent quantum efficiency reaches approximately 1000% to 10000%. Consequently, the change in current I when electromagnetic waves irradiate the electromagnetic wave detector 100 of this embodiment is greater than the change in current when electromagnetic waves are incident on a conventional electromagnetic wave detector that does not produce an optical gating effect. Therefore, compared to conventional electromagnetic wave detectors, the electromagnetic wave detector 100 of this embodiment has higher sensitivity.

[0159] Implementation method 2.

[0160] Next, use Figure 8 The structure of the electromagnetic wave detector 100 in Embodiment 2 will be described below. Unless otherwise specified, Embodiment 2 has the same structure, manufacturing method, and effects as Embodiment 1 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 1, and the description will not be repeated.

[0161] In this embodiment, the control electrode 2c and the second electrode 2b sandwich the semiconductor layer 4. The second electrode 2b is directly connected to the semiconductor layer 4. The second insulating film 3b covers the control electrode 2c. The two-dimensional material layer 1 covers the semiconductor layer 4, the first insulating film 3a, and the second insulating film 3b. The control electrode 2c is disposed below the two-dimensional material layer 1. Furthermore, the portion of the control electrode 2c extending along the inside or front side of the paper is connected to a second power supply circuit (not shown). The electromagnetic wave detector 100 of this embodiment differs from the electromagnetic wave detector 100 of Embodiment 1 in that the control electrode 2c is disposed below the graphene layer.

[0162] Next, the manufacturing method of the electromagnetic wave detector 100 according to Embodiment 2 will be described.

[0163] In the manufacturing method of the electromagnetic wave detector 100 of this embodiment, after sequentially performing the first insulating film formation step, the opening OP formation step, the second insulating film formation step, and the control electrode formation step, a two-dimensional material layer formation step is performed. That is, after forming the first insulating film 3a, the second insulating film 3b, and the control electrode 2c, the two-dimensional material layer 1 is formed. Therefore, the two-dimensional material layer 1 is formed last.

[0164] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 2 can also be applied to other embodiments.

[0165] Next, the effects of this implementation method will be explained.

[0166] According to the electromagnetic wave detector 100 of Embodiment 2, such as Figure 8 As shown, the two-dimensional material layer 1 covers the semiconductor layer 4, the first insulating film 3a, and the second insulating film 3b. Therefore, the two-dimensional material layer 1 can be formed after the formation of the first insulating film 3a, the second insulating film 3b, and the control electrode 2c. Consequently, damage to the two-dimensional material layer 1 due to the formation process of the second insulating film 3b and the control electrode 2c can be suppressed. Furthermore, residues such as photoresist can be suppressed. Therefore, the performance of the electromagnetic wave detector 100 can be improved.

[0167] Implementation method 3.

[0168] Next, use Figures 9-12 The structure of the electromagnetic wave detector 100 in Embodiment 3 will be described below. Unless otherwise specified, Embodiment 3 has the same structure, manufacturing method, and effects as Embodiment 1 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 1, and the description will not be repeated.

[0169] Figure 9 A top view of the first structure of Embodiment 3 is shown for schematic purposes. Figure 9 To and Figure 2A magnified view of a portion of the region corresponding to region IX. Additionally, Figures 10-12 To and Figure 9 A top view of the corresponding area.

[0170] like Figure 9 As shown, in this embodiment, the electromagnetic wave detector 100 is configured to generate surface plasmon resonance at the control electrode 2c. The material of the control electrode 2c is the material that generates surface plasmon resonance. The material of the control electrode 2c is the material that generates surface plasmon resonance by means of electromagnetic waves having a detection wavelength. When the detection wavelength of the electromagnetic wave detector 100 is in the range of visible light wavelength to infrared wavelength, the material of the control electrode 2c is, for example, aluminum (Al), gold (Au), etc. Furthermore, a plasmon resonance-generating coating material can be used to coat the surface of the control electrode 2c where electromagnetic waves are incident. Examples of plasmon resonance-generating coating materials include titanium nitride (TiN), transparent conductive films (ITO films: indium tin oxide films), graphene, etc. The coating material can be a material other than a metal. Alternatively, the electrode itself can be, for example, graphene. Graphene can be a single layer or multiple layers; in the case of multiple layers, it can be graphite.

[0171] like Figure 9 As shown, the control electrode 2c includes a plurality of control electrode portions 2c0. Adjacent control electrode portions 2c0 are arranged at intervals that allow surface plasmon resonance to occur in each of the plurality of control electrode portions 2c0. The plurality of control electrode portions 2c0 are arranged periodically. In this embodiment, the periodic arrangement of the plurality of control electrode portions 2c0 means that the interval between adjacent control electrode portions 2c0 is constant.

[0172] The wavelength at which surface plasmon resonance is generated in the control electrode section 2c0 is determined by the width w of the control electrode section 2c0, the spacing g between adjacent control electrode sections 2c0, and the period p. The width w is the dimension of the control electrode section 2c0 along the X-axis. The spacing g is the distance between adjacent control electrode sections 2c0 along the X-axis. The period p is the sum of the spacing g and the width w. In this embodiment, the width, spacing, and period along the X-axis are described, but the electromagnetic wave detector 100 may also have the same structure regarding the width, spacing, and period along the Y-axis.

[0173] For example, in the infrared wavelength range, when the material on the incident side of the control electrode 2c0 is gold (Au), if the width w is 2 μm and the spacing g is 1 μm, the plasma resonance wavelength is 10 μm. By appropriately adjusting the width w, spacing g, and period p, plasma resonance can also be generated at wavelengths outside the aforementioned infrared wavelength range. Figure 9 and Figure 10 It is equipped with three control electrode sections 2c0, in Figure 11 and Figure 12 Nine control electrode sections 2c0 are configured, but the number of control electrode sections 2c0 is not limited. Furthermore, in... Figure 9 and Figure 10 In this configuration, multiple control electrode sections 2c0 are periodically arranged in a one-dimensional manner, but they can also be arranged as follows: Figure 11 and Figure 12 The control electrode sections 2c0 are arranged periodically in a two-dimensional manner. Whether the multiple control electrode sections 2c0 are arranged in a one-dimensional or two-dimensional manner, plasma resonance is generated in the control electrode sections 2c0 by appropriately adjusting the width w, spacing g, and period p. If these parameters are different, the plasma resonance wavelength will also be different. Specifically, in... Figures 9-12 In the construction, the width w is the most dominant parameter, but which parameter is dominant depends on the construction.

[0174] As long as plasma resonance is generated in the control electrode section 2c0, the shape and arrangement of the control electrode section 2c0 can be determined as appropriate. Plasma resonance can be generated in the control electrode section 2c0 regardless of whether it is a rectangle, square, triangle, or other polygonal or circular shape. Furthermore, the control electrode section 2c0 can be fractal. Multiple control electrode sections 2c0 can be arranged in a concentric circle.

[0175] When the semiconductor layer 4 is thin, a metamaterial structure consisting of a second electrode 2b, a control electrode 2c, a second insulating film 3b, and the semiconductor layer 4 is formed by sequentially stacking metal, dielectric, and metal. When forming the metamaterial structure, the dominant parameter determining the plasma resonance wavelength is the width w of the control electrode portion 2c0.

[0176] like Figure 9 and such Figure 10 As shown, each of the multiple control electrode units 2c0 can extend along the Y-axis direction. Each of the multiple control electrode units 2c0 can be arranged along the X-axis direction.

[0177] like Figure 10 As shown, the plurality of control electrode portions 2c0 may include a third control electrode portion 2c3, a fourth control electrode portion 2c4, and a fifth control electrode portion 2c5. The third control electrode portion 2c3, the fourth control electrode portion 2c4, and the fifth control electrode portion 2c5 each have widths w3, w4, and w5 that are different from each other. The spacing g between the third control electrode portion 2c3 and the fourth control electrode portion 2c4 and the spacing g between the fourth control electrode portion 2c4 and the fifth control electrode portion 2c5 are the same. Alternatively, the spacing g may be different.

[0178] like Figure 11As shown, adjacent control electrode sections 2c0 can be arranged at equal intervals g in each of the X-axis and Y-axis directions.

[0179] like Figure 12 As shown, the plurality of control electrode portions 2c0 may include a plurality of sixth control electrode portions 2c6, a plurality of seventh control electrode portions 2c7, and a plurality of eighth control electrode portions 2c8. Each of the plurality of sixth control electrode portions 2c6 has a width w6. Each of the plurality of seventh control electrode portions 2c7 has a width w7. Each of the plurality of eighth control electrode portions 2c8 has a width w8. The widths w6, w7, and w8 are all different. The spacing g1 between adjacent sixth control electrode portions 2c6 and seventh control electrode portions 2c7 is smaller than the spacing g2 between adjacent seventh control electrode portions 2c7 and eighth control electrode portions 2c8. Furthermore, the spacing between adjacent sixth control electrode portions 2c6 is the same. The spacing between adjacent seventh control electrode portions 2c7 is the same. The spacing between adjacent eighth control electrode portions 2c8 is the same.

[0180] exist Figure 10 and Figure 12 In this process, when at least one of the parameters w, p, and g is different, the plasma resonance wavelengths in different regions are constructed to be different, resulting in a variety of plasma resonance wavelengths. When different plasma resonance wavelengths are close to each other, the bandwidth of the resonance wavelength becomes wider.

[0181] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 3 can also be applied to other embodiments.

[0182] Next, the effects of this implementation method will be explained.

[0183] According to the electromagnetic wave detector 100 of Embodiment 3, the material of the control electrode 2c is a material that generates surface plasmon resonance. Therefore, surface plasmon resonance can be generated at the control electrode 2c. Consequently, the sensitivity of the electromagnetic wave detector 100 can be improved. Furthermore, the mechanism by which the sensitivity of the electromagnetic wave detector 100 is improved due to surface plasmon resonance will be explained later.

[0184] like Figure 9 As shown, adjacent control electrode sections 2c0 among the plurality of control electrode sections 2c0 are arranged at intervals that allow surface plasmon resonance to occur at each control electrode section of the plurality of control electrode sections 2c0. Therefore, surface plasmon resonance can be generated at each control electrode section of the plurality of control electrode sections 2c0. Consequently, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0185] Next, the mechanism by which the sensitivity of the electromagnetic wave detector 100 is enhanced due to surface plasmon resonance will be explained. When plasmon resonance occurs at the control electrode 2c, the electromagnetic field is enhanced in and around the control electrode 2c. This enhancement of the electromagnetic field is also referred to as localized surface plasmon resonance. The electromagnetic field is also simultaneously enhanced in the two-dimensional material layer 1 connected to the control electrode 2c. Therefore, the photocarrier absorption rate of the two-dimensional material layer 1 increases. By appropriately designing the width w, spacing g, and period p, the photocarrier absorption rate of the two-dimensional material layer 1 is increased to nearly 100%. Furthermore, the electromagnetic field is also simultaneously enhanced in the semiconductor layer 4. As a result, the photoelectric conversion efficiency of the semiconductor layer 4 is enhanced, thus increasing the number of photocarriers generated in the semiconductor layer 4.

[0186] Based on the above, since more photocarriers are absorbed by the two-dimensional material layer 1, the current flowing through the two-dimensional material layer 1 increases. Furthermore, since more photocarriers are generated in the semiconductor layer 4, the current flowing through the two-dimensional material layer 1 increases. The current flowing through the two-dimensional material layer 1 is ultimately extracted as a photodetector signal, thus increasing the photodetector signal. Furthermore, the magnitude of the optical gating effect in the two-dimensional material layer 1 is proportional to the magnitude of the current flowing through it, thus strengthening the optical gating effect. Therefore, the final photodetector signal is further enhanced. Thus, the detection performance of the electromagnetic wave detector 100 can be improved.

[0187] Furthermore, the electromagnetic field enhancement based on plasmon resonance is generated only by electromagnetic waves having a plasmon resonance wavelength. Therefore, the electromagnetic field is selectively enhanced by electromagnetic waves having a plasmon resonance wavelength. Consequently, the sensitivity of the electromagnetic wave detector 100 is selectively enhanced at the plasmon resonance wavelength. Therefore, by setting the detection wavelength to the plasmon resonance wavelength, the electromagnetic wave detector 100 can selectively detect electromagnetic waves having the detection wavelength. Alternatively, when the plasmon resonance wavelength is set to multiple wavelengths, the detection sensitivity is enhanced at multiple wavelengths.

[0188] like Figure 9 As shown, the plurality of control electrode sections 2c0 include a first control electrode section 2c1. The first control electrode section 2c1 is separated from the second insulating film 3b (see reference). Figure 1 ) connected to the first part of the two-dimensional material layer 1 (refer to Figure 1 Furthermore, when plasma resonance occurs at the electrodes, the electromagnetic field is strongly confined to the lower end of the electrodes. Therefore, compared to the second control electrode section 2c2 (which will be explained later), Figure 13 The plasma resonance generated at the first control electrode 2c1 makes the electromagnetic field stronger. Therefore, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0189] like Figure 9As shown, each of the multiple control electrode sections 2c0 extends along the Y-axis direction. The multiple control electrode sections 2c0 are arranged along the X-axis direction. Therefore, plasma resonance occurs only when the electric field of the electromagnetic wave incident on the electromagnetic wave detector 100 is parallel to the X-axis direction, as the electromagnetic wave is absorbed. Furthermore, when the electric field of the electromagnetic wave is parallel to the Y-axis direction, the electromagnetic wave is not absorbed. That is, the electromagnetic wave detector 100 has polarization selectivity. Thus, the electromagnetic wave detector 100 can selectively detect polarization. Furthermore, the shapes of each of the multiple control electrode sections 2c0 are as follows... Figure 11 As shown, the electromagnetic wave detector 100 has no polarization selectivity when it is a square or a circle.

[0190] like Figure 10 and Figure 12 As shown, the multiple control electrode sections 2c0 have different widths, spacings, and periods. Therefore, the plasma resonance wavelength becomes a variety of wavelengths. Compared to... Figure 9 and Figure 11 When the multiple control electrode sections 2c0 shown have the same width, spacing, and period, resonance is generated at a wider range of wavelengths. If the resonant wavelengths are similar, it is equivalent to a wider bandwidth of the resonant wavelength. Therefore, the detection wavelength of the electromagnetic wave detector 100 can be widened. That is, the bandwidth of the detection wavelength of the electromagnetic wave detector 100 can be widened.

[0191] Implementation method 4.

[0192] Next, use Figure 13 The structure of the electromagnetic wave detector 100 in Embodiment 4 will be described below. Unless otherwise specified, Embodiment 4 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 3, and the description will not be repeated.

[0193] like Figure 13 As shown, in this embodiment, the plurality of control electrode portions 2c0 include a first control electrode portion 2c1 and a second control electrode portion 2c2. The second control electrode portion 2c2 is connected to the second portion 1b via the second insulating film 3b. The second control electrode portion 2c2 is disposed above the first insulating film 3a. Therefore, the second control electrode portion 2c2 is disposed outside the opening OP. The second control electrode portion 2c2 is not disposed within the opening OP. The second insulating film 3b, the two-dimensional material layer 1, and the first insulating film 3a are sequentially stacked between the second control electrode portion 2c2 and the semiconductor layer 4. The shortest distance between the first control electrode portion 2c1 and the semiconductor layer 4 is shorter than the shortest distance between the second control electrode portion 2c2 and the semiconductor layer 4.

[0194] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 4 can also be applied to other embodiments.

[0195] Next, the effects of this implementation method will be explained.

[0196] According to the electromagnetic wave detector 100 of embodiment 4, such as Figure 13 As shown, the second control electrode portion 2c2 is connected to the second portion 1b via the second insulating film 3b. Therefore, at least one of the plurality of control electrode portions 2c0 is not disposed within the opening OP. Consequently, compared to the case where all of the plurality of control electrode portions 2c0 are disposed within the opening OP, the size of the electromagnetic wave detector 100 along the in-plane direction of the semiconductor layer 4 can be reduced.

[0197] Implementation method 5.

[0198] Next, use Figure 14 The structure of the electromagnetic wave detector 100 in Embodiment 5 will be described below. Unless otherwise specified, Embodiment 5 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 3, and the description will not be repeated.

[0199] like Figure 14 As shown, the first electrode 2a includes a first side portion 2aa and a second side portion 2ab. The second side portion 2ab and the first side portion 2aa sandwich an opening OP. A through hole TH is provided in the first electrode 2a. The through hole TH communicates with the opening OP. The through hole TH can be located at the center of the first electrode 2a. That is, the shape of the first electrode 2a is annular with the through hole TH as its center. Furthermore, in Figure 14 The first electrode 2a is ring-shaped, but it can also be U-shaped.

[0200] The two-dimensional material layer 1 includes a first end 11 and a second end 12. The second end 12 is opposite to the first end 11. The first end 11 is directly connected to the first edge 2aa. The second end 12 is directly connected to the second edge 2ab. The two-dimensional material layer 1 extends from the first edge 2aa to the second edge 2ab through a through-hole TH. Figure 14 The two-dimensional material layer 1 is partially directly connected to the first electrode 2a, and the two-dimensional material layer 1 can also be directly connected to the entire surface of the first electrode 2a.

[0201] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 5 can also be applied to other embodiments.

[0202] Next, the effects of this implementation method will be explained.

[0203] According to the electromagnetic wave detector 100 of this embodiment, the first end 11 is directly connected to the first side 2aa, and the second end 12 is directly connected to the second side 2ab. Therefore, compared to the case where neither end of the two-dimensional material layer 1 is directly connected to the first electrode 2a, the current conducted from the two-dimensional material layer 1 to the first electrode 2a is increased. Consequently, the sensitivity of the electromagnetic wave detector 100 can be improved. Furthermore, when the two-dimensional material layer 1 is directly connected to the entire surface of the first electrode 2a, the sensitivity of the electromagnetic wave detector 100 can be further improved.

[0204] Implementation method 6.

[0205] Next, use Figure 15 The structure of the electromagnetic wave detector 100 in Embodiment 6 will be described below. Unless otherwise specified, Embodiment 6 has the same structure, manufacturing method, and effects as Embodiment 5 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 5, and the description will not be repeated.

[0206] like Figure 15 As shown, the two-dimensional material layer 1 of this embodiment includes a first end 11 and a second end 12. The first end 11 is directly connected to the first electrode 2a. The first end 11 is disposed outside the opening OP. The second end 12 is disposed away from the first electrode 2a. The second end 12 is not directly connected to the first electrode 2a. The second end 12 is disposed inside the opening OP.

[0207] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 5 can also be applied to other embodiments.

[0208] Next, the effects of this implementation method will be explained.

[0209] According to the electromagnetic wave detector 100 of embodiment 5, such as Figure 15 As shown, the first end 11 is directly connected to the first electrode 2a. The second end 12 is disposed away from the first electrode 2a. Therefore, compared to the case where both ends of the two-dimensional material layer 1 are connected to the first electrode 2a, the contact between the two-dimensional material layer 1 and the semiconductor layer 4 is better.

[0210] Assuming that both ends of the two-dimensional material layer 1 are connected to the first electrode 2a, it is possible that due to deflection in the two-dimensional material layer 1, only the central portion of the two-dimensional material layer 1 will contact the semiconductor layer 4. When only the central portion of the two-dimensional material layer 1 contacts the semiconductor layer 4, good characteristics may not be obtained.

[0211] According to this embodiment, the second end 12 is disposed away from the first electrode 2a. Therefore, the two-dimensional material layer 1 and the semiconductor layer 4 have good contact.

[0212] When the contact between the two-dimensional material layer 1 and the semiconductor layer 4 is good, the migration of the generated photocarriers is not hindered by the electromagnetic wave detector 100. As a result, the detection signal of the electromagnetic wave detector 100 increases. Furthermore, the noise decreases. Therefore, the performance of the electromagnetic wave detector 100 can be improved.

[0213] Furthermore, when the optical gating effect is dominant, the sensitivity of the electromagnetic wave detector 100 is less dependent on the contact area between the two-dimensional material layer 1 and the semiconductor layer 4. Therefore, when the contact state between the two-dimensional material layer 1 and the semiconductor layer 4 is improved, the pathway for photocarriers becomes larger. Consequently, the pixel area (area of ​​the semiconductor layer 4) of the electromagnetic wave detector 100 can be reduced. Thus, the electromagnetic wave detector 100 can be miniaturized.

[0214] Implementation method 7.

[0215] Next, use Figure 16 The structure of the electromagnetic wave detector 100 in Embodiment 7 will be described below. Unless otherwise specified, Embodiment 7 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 3, and the description will not be repeated.

[0216] like Figure 16 As shown, the electromagnetic wave detector 100 of this embodiment further includes a buffer layer 5. The buffer layer 5 is sandwiched between the two-dimensional material layer 1 and the semiconductor layer 4. The buffer layer 5 electrically connects the semiconductor layer 4 to the first portion 1a. Therefore, in this embodiment, the first portion 1a is connected to the semiconductor layer 4 through the buffer layer 5. The thickness of the buffer layer 5 is thinner than that of the first insulating film 3a. The plurality of control electrode portions 2c0 include a ninth control electrode portion 2c9. The ninth control electrode portion 2c9 is connected to the buffer layer 5 through the second insulating film 3b and the two-dimensional material layer 1.

[0217] The buffer layer 5 has a thickness sufficient to form a tunnel current between the two-dimensional material layer 1 and the semiconductor layer 4. The buffer layer 5 is, for example, an insulating film with a thickness of 1 nm or more but less than 10 nm. The buffer layer 5 is thinner than the first insulating film 3a. The insulating film can be, for example, a metal oxide such as alumina or hafnium oxide (HfO2), a semiconductor oxide such as silicon oxide, or a semiconductor nitride such as silicon nitride (Si3N4).

[0218] The method for fabricating the buffer layer 5 can be determined as appropriate, and can be selected from methods such as ALD (Atomic Layer Deposition), vacuum evaporation, and sputtering. Alternatively, the buffer layer 5 can be formed by oxidizing or nitriding the surface of the semiconductor layer 4. Furthermore, the buffer layer 5 can be a natural oxide film formed on the surface of the semiconductor layer 4.

[0219] In the modified embodiment 7, the thickness of the buffer layer 5 is greater than the thickness required to form a tunneling current between the two-dimensional material layer 1 and the semiconductor layer 4, but thinner than the first insulating film 3a. Therefore, photocarriers generated in the semiconductor layer 4 are not injected into the two-dimensional material layer 1 through the buffer layer 5. Furthermore, an optical gating effect occurs. Because the thickness of the buffer layer 5 is thinner than the first insulating film 3a, a gradient in carrier density is generated between the two-dimensional material layer 1 in the region contacting the first insulating film 3a and the two-dimensional material layer 1 in contact with the buffer layer 5.

[0220] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 7 and its variations can also be applied to other embodiments.

[0221] Next, the effects of this implementation method will be explained.

[0222] According to the electromagnetic wave detector 100 of embodiment 7, such as Figure 16 As shown, the electromagnetic wave detector 100 also includes a buffer layer 5. Therefore, a carrier density gradient is generated between the two-dimensional material layer 1 (part 2, b) in the region contacting the first insulating film 3a and the two-dimensional material layer 1 (part 1a) in the region contacting the buffer layer 5. Consequently, the mobility of the two-dimensional material layer 1 increases, and therefore the photocurrent extracted from the two-dimensional material layer 1 increases. Thus, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0223] like Figure 16 As shown, the buffer layer 5 has a thickness sufficient to form a tunneling current between the semiconductor 4 and the two-dimensional material layer 1. Therefore, photocarriers generated in the semiconductor layer 4 are injected into the two-dimensional material layer 1 through the buffer layer 5. Consequently, the sensitivity of the electromagnetic wave detector 100 is improved due to the large photocurrent injected into the graphene.

[0224] like Figure 16 As shown, the plurality of control electrode sections 2c0 include a ninth control electrode section 2c9. The ninth control electrode section 2c9 is connected to the buffer layer 5 through the second insulating film 3b and the two-dimensional material layer 1. Therefore, through the ninth control electrode section 2c9, in addition to controlling the Fermi level of the two-dimensional material layer 1, the magnitude of the tunneling current can also be controlled. Furthermore, by applying a bias voltage V1, the magnitude of the tunneling current can be enhanced. As a result, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0225] Implementation method 8.

[0226] Next, use Figure 17 The structure of the electromagnetic wave detector 100 in Embodiment 8 will be described below. Unless otherwise specified, Embodiment 8 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 3, and the description will not be repeated.

[0227] like Figure 17 As shown, the electromagnetic wave detector 100 of this embodiment also includes a connecting conductor 6. The two-dimensional material layer 1 is electrically connected to the semiconductor layer 4 through the connecting conductor 6. The connecting conductor 6 is disposed inside the opening OP. The connecting conductor 6 is in contact with the first insulating film 3a.

[0228] A two-dimensional material layer 1 is superimposed on the upper surface of the connecting conductor 6. The lower surface of the connecting conductor 6 is electrically connected to the first surface 4a of the semiconductor layer 4. The two-dimensional material layer 1 is electrically connected to the upper surface of the connecting conductor 6. The position of the upper surface of the connecting conductor 6 is the same as the position of the upper surface of the first insulating film 3a. The two-dimensional material layer 1 extends in a planar manner from the upper surface of the first insulating film 3a to the upper surface of the connecting conductor 6 without any bends.

[0229] Preferably, the connecting conductor 6 is bonded to the semiconductor layer 4 via an ohmic junction. Additionally, it is preferable that the connecting conductor 6 has high transmittance at the detection wavelength.

[0230] The material of the conductor 6 is the same as that of the first electrode 2a, the second electrode 2b, and the control electrode 2c. For example, when the material of the semiconductor layer 4 is indium antimonide (InSb), considering the difference in Fermi level with the two-dimensional material layer 1, it is preferable that the material of the conductor 6 is nickel (Ni).

[0231] The contact resistance between the conductive element 6 and the two-dimensional material layer 1 is less than the contact resistance between the two-dimensional material layer 1 and the semiconductor layer 4. The contact resistance between the conductive element 6 and the semiconductor layer 4 is less than the contact resistance between the two-dimensional material layer 1 and the semiconductor layer 4. The sum of the contact resistance between the conductive element 6 and the two-dimensional material layer 1 and the contact resistance between the conductive element 6 and the semiconductor layer 4 is less than the contact resistance between the two-dimensional material layer 1 and the semiconductor layer 4.

[0232] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 8 can also be applied to other embodiments.

[0233] Next, the effects of this implementation method will be explained.

[0234] According to the electromagnetic wave detector 100 of embodiment 8, such as Figure 17 As shown, the two-dimensional material layer 1 is electrically connected to the semiconductor layer 4 via a connecting conductor 6. The sum of the contact resistance between the connecting conductor 6 and the two-dimensional material layer 1 and the contact resistance between the connecting conductor 6 and the semiconductor layer 4 is less than the contact resistance between the two-dimensional material layer 1 and the semiconductor layer 4. Therefore, compared to the case where the two-dimensional material layer 1 and the semiconductor layer 4 are directly bonded, the contact resistance can be reduced. In addition, since the two-dimensional material layer 1 and the semiconductor layer 4 are bonded through a Schottky junction, the attenuation of photocurrent can be suppressed.

[0235] like Figure 17 As shown, the position of the upper surface of the conductive body 6 is the same as the position of the upper surface of the first insulating film 3a. Therefore, the two-dimensional material layer 1 is formed horizontally without bending, thus increasing the mobility of charge carriers in the two-dimensional material layer 1. Since the optical gating effect is proportional to the mobility, the detection sensitivity of the electromagnetic wave detector 100 can be improved.

[0236] Implementation method 9.

[0237] Next, use Figures 18-24 The structure of the electromagnetic wave detector 100 in Embodiment 9 will be described below. Unless otherwise specified, Embodiment 9 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 3, and the description will not be repeated.

[0238] like Figure 18 As shown, the semiconductor layer 4 in this embodiment includes a first semiconductor portion 41 and a second semiconductor portion 42. The second semiconductor portion 42 has a different conductivity type than the first semiconductor portion 41. That is, the first semiconductor portion 41 and the second semiconductor portion 42 are photodiodes with different conductivity types. The first semiconductor portion 41 has a first conductivity type. The second semiconductor portion 42 has a second conductivity type. The first conductivity type is the opposite of the second conductivity type. Therefore, the charge carriers doped into the first semiconductor portion 41 are different from the charge carriers doped into the second semiconductor portion 42.

[0239] The first semiconductor section 41 is bonded to the second semiconductor section 42. The first semiconductor section 41 is bonded to the second semiconductor section 42 directly below the opening OP. Therefore, a pn junction is formed inside the semiconductor layer 4.

[0240] The second semiconductor section 42 has an absorption wavelength different from that of the first semiconductor section 41. The absorption wavelength of the second semiconductor section 42 may be greater than or less than that of the first semiconductor section 41. The absorption wavelength of the second semiconductor section 42 may be partially the same as that of the first semiconductor section 41, as long as it is not exactly the same as the absorption wavelength of the first semiconductor section 41.

[0241] A tunnel diode can be used as the semiconductor layer 4, which includes a first semiconductor section 41 and a second semiconductor section 42. This allows a large photocurrent to be generated only when electromagnetic waves irradiate the semiconductor layer 4. Consequently, the photocurrent is injected into the two-dimensional material layer 1, and a change in the electric field is generated in the two-dimensional material layer 1. This improves the sensitivity of the electromagnetic wave detector 100.

[0242] Semiconductor layer 4 may further include a third semiconductor portion 43. The third semiconductor portion 43 may have any of the first and second conductivity types. The third semiconductor portion 43 is bonded to at least any of the first semiconductor portion 41 and the second semiconductor portion 42. Preferably, the third semiconductor portion 43 is bonded to both the first semiconductor portion 41 and the second semiconductor portion 42. The third semiconductor portion 43 may surround the first semiconductor portion 41 and the second semiconductor portion 42 along the in-plane direction of semiconductor layer 4.

[0243] The first electrode 2a may include a pair of first electrode portions 2a1 configured to clamp the opening OP. Each pair of first electrode portions 2a1 is connected to the first insulating film 3a.

[0244] like Figure 19 As shown, at the opening OP, the first semiconductor portion 41 and the second semiconductor portion 42 are exposed from the first insulating film 3a, etc. Therefore, electromagnetic waves irradiate the first semiconductor portion 41, the second semiconductor portion 42, and the interface between the first semiconductor portion 41 and the second semiconductor portion 42.

[0245] Next, use Figure 20 The structure of the first variation of embodiment 9 will be explained.

[0246] like Figure 20 As shown, the first electrode 2a is connected to each of the first semiconductor section 41 and the second semiconductor section 42. A pair of first electrode sections 2a1 are respectively connected to the first semiconductor section 41 and the second semiconductor section 42. Therefore, the first semiconductor section 41 and the second semiconductor section 42 are each biased by a voltage V1 via the first electrode 2a.

[0247] Next, use Figure 21 and Figure 22 The structure of the second variation of embodiment 9 will be explained.

[0248] like Figure 21 and Figure 22 As shown, the second semiconductor portion 42 includes a pair of second semiconductor portions 420. The pair of second semiconductor portions 420 sandwich the first semiconductor portion 41. Therefore, each of the pair of second semiconductor portions 420 is bonded to the first semiconductor portion 41. Consequently, there are two bonding portions to the first semiconductor portion 41. Therefore, two pn junctions are formed in the first semiconductor portion 41. Thus, the semiconductor layer 4 is configured as any photoresistor between a pnp photoresistor and an npn photoresistor.

[0249] Next, use Figure 23 and Figure 24 The structure of the third variation of embodiment 9 will be explained.

[0250] like Figure 23As shown, the first semiconductor portion 41 is bonded to the second semiconductor portion 42 along the in-plane direction of the semiconductor layer 4. Therefore, the bonding interface extends along the in-plane direction of the semiconductor layer 4. The second semiconductor portion 42 is embedded in the first semiconductor portion 41. The two-dimensional material layer 1 is bonded to the second semiconductor portion 42 through a thin portion of the first semiconductor portion 41. The bonding interface extends directly beneath the semiconductor layer 4 along the in-plane direction of the semiconductor layer 4. Figure 24 As shown, the second semiconductor section 42 is not exposed from the first insulating film 3a.

[0251] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 9 can also be applied to other embodiments.

[0252] Next, the effects of this implementation method will be explained.

[0253] According to the electromagnetic wave detector 100 of embodiment 9, such as Figure 18 As shown, the first semiconductor section 41 is bonded to the second semiconductor section 42. Therefore, a pn junction is formed in the semiconductor layer 4. Consequently, photocarriers can be generated from the pn junction in the semiconductor layer 4. The photocarriers generated in the pn junction can be extracted from the two-dimensional material layer 1. Furthermore, the region in the semiconductor layer 4 directly above the bonding interface is affected by a change in the local electric field at the bonding interface between the first semiconductor section 41 and the second semiconductor section 42. This causes a change in the conductivity of the two-dimensional material layer 1, thereby enhancing the optical gating effect. Therefore, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0254] The second semiconductor section 42 has a different absorption wavelength than the first semiconductor section 41. Therefore, compared to the case where the semiconductor layer 4 is composed of a single semiconductor section, the absorption wavelength of the semiconductor layer 4 is wider. Consequently, the detection wavelength bandwidth of the electromagnetic wave detector 100 can be broadened.

[0255] According to the electromagnetic wave detector 100 of the first modification of embodiment 9, such as Figure 20 As shown, the first electrode 2a is connected to each of the first semiconductor section 41 and the second semiconductor section 42. Therefore, a voltage can be applied to both the first semiconductor section 41 and the second semiconductor section 42 while simultaneously applying a voltage to the two-dimensional material layer 1. Consequently, the depletion layer generated in the first semiconductor section 41 and the second semiconductor section 42 can be enlarged, thereby increasing the photocurrent. Therefore, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0256] According to the electromagnetic wave detector 100 of the second modification of embodiment 9, such as Figure 21As shown, a pair of second semiconductor portions 420 sandwich a first semiconductor portion 41. Therefore, the interface between the first semiconductor portion 41 and the second semiconductor portion 42 is larger than when the second semiconductor portion 42 is composed of a single component. Furthermore, the area of ​​the interface in contact with the two-dimensional material layer 1 is larger than when the second semiconductor portion 42 is composed of a single component. Therefore, the effect of the local electric field change caused by electromagnetic waves irradiating the semiconductor layer 4 on the two-dimensional material layer 1 can be increased. Therefore, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0257] like Figure 21 As shown, a pair of second semiconductor portions 420 sandwich a first semiconductor portion 41. This allows the semiconductor layer 4 to function as either an npn or pnp photoresistor. Therefore, as the intensity of light irradiating the semiconductor layer 4 decreases, the resistance of the first semiconductor portion 41 and the second semiconductor portion 42 increases. Consequently, photocurrent flows through the first semiconductor portion 41 and the second semiconductor portion 42 only when light irradiates the semiconductor layer 4. Therefore, an electric field change occurs only when light irradiates the semiconductor layer 4, thereby improving the sensitivity of the electromagnetic wave detector 100.

[0258] According to the electromagnetic wave detector 100 of the third variation of embodiment 9, such as Figure 23 As shown, the first semiconductor portion 41 is bonded to the second semiconductor portion 42 along the in-plane direction of the semiconductor layer 4. Therefore, the bonding interface between the first semiconductor portion 41 and the second semiconductor portion 42 extends along the in-plane direction of the semiconductor layer 4. Electromagnetic waves irradiate the semiconductor layer 4 from a direction intersecting the in-plane direction of the semiconductor layer 4. Therefore, the intensity of the electromagnetic waves irradiating the bonding interface is greater than when the bonding interface extends along the intersecting direction. Consequently, the photocurrent increases, thus improving the sensitivity of the electromagnetic wave detector 100.

[0259] Implementation method 10.

[0260] Next, use Figures 25-27 The structure of the electromagnetic wave detector 100 in Embodiment 10 will be described below. Unless otherwise specified, Embodiment 10 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures that are the same as those in Embodiment 3, and the description will not be repeated.

[0261] like Figure 25 As shown, in this embodiment, the opening OP includes a plurality of opening portions OP1 spaced apart from each other. Furthermore, for ease of explanation, in... Figure 25 In the middle, the dashed line represents the transition between the two-dimensional material layer 1 and the control electrode 2c (refer to...). Figure 1 (Not shown in the diagram.) The two-dimensional material layer 1 is connected to the semiconductor layer 4 at each of the multiple openings OP1. (See diagram.) Figure 25 and Figure 26 As shown, two openings OP1 can be provided. Figure 27 As shown, OP1 can be provided with four openings. Furthermore, in Figure 26 and Figure 27 In the figure, the outline of the two-dimensional material layer 1 and the outline of the control electrode 2c are shown by dashed lines.

[0262] Furthermore, the structure of the electromagnetic wave detector 100 in Embodiment 10 can also be applied to other embodiments.

[0263] Next, the effects of this implementation method will be explained.

[0264] According to the electromagnetic wave detector 100 of embodiment 10, such as Figure 25 As shown, the two-dimensional material layer 1 is connected to the semiconductor layer 4 at each of the multiple openings OP1. Therefore, compared to the case where there is a single opening OP, the two-dimensional material layer 1 contacts the semiconductor layer 4 at more locations. Consequently, during the manufacturing process, the unevenness of the contact between the two-dimensional material layer 1 and the semiconductor layer 4 can be reduced. Therefore, the performance of the electromagnetic wave detector 100 can be improved.

[0265] Implementation method 11.

[0266] Next, use Figure 28 The structure of the electromagnetic wave detector 100 in Embodiment 11 will be described below. Unless otherwise specified, Embodiment 11 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures that are the same as those in Embodiment 3, and the description will not be repeated.

[0267] like Figure 28 As shown, in this embodiment, the first insulating film 3a includes a tapered portion 3a1. The tapered portion 3a1 is configured such that its thickness varies as it approaches the opening OP from the first electrode 2a. That is, a gradient is provided for the first insulating film 3a. The tapered portion 3a1 is configured such that its thickness decreases as it approaches the opening OP from the first electrode 2a. The second portion 1b of the two-dimensional material layer 1 is directly connected to the tapered portion 3a1.

[0268] The tapered portion 3a1 can be formed by depositing the first insulating film 3a while the semiconductor layer 4 is tilted. Alternatively, the tapered portion 3a1 can be formed by dry etching the first insulating film 3a while the semiconductor layer 4 is tilted. As long as the thickness of the tapered portion 3a1 is configured to deform as it approaches the opening OP from the first electrode 2a, the tapered portion 3a1 is appropriately formed.

[0269] Furthermore, the structure of the electromagnetic wave detector 100 in embodiment 11 can also be applied to other embodiments.

[0270] Next, the effects of this implementation method will be explained.

[0271] According to the electromagnetic wave detector 100 of embodiment 11, such as Figure 28 As shown, the tapered portion 3a1 is configured such that its thickness varies as it approaches the opening OP from the first electrode 2a. Therefore, when electromagnetic waves are irradiated onto the semiconductor layer 4, the degree of change in the electric field within the two-dimensional material layer 1 changes locally. In other words, when electromagnetic waves are irradiated onto the semiconductor layer 4, causing a change in the electric field applied to the two-dimensional material layer 1, the degree of this change in electric field varies locally depending on the thickness of the first insulating film 3a. Consequently, the mobility of charge carriers in the two-dimensional material layer 1 increases, and the detection sensitivity of the electromagnetic wave detector 100 increases.

[0272] Implementation method 12.

[0273] Next, use Figure 29 The structure of the electromagnetic wave detector 100 in Embodiment 12 will be described below. Unless otherwise specified, Embodiment 12 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 3, and the description will not be repeated.

[0274] In this embodiment, a gap (GAP) is provided between the first insulating film 3a and the two-dimensional material layer 1. That is, unlike the electromagnetic wave detector 100 in Embodiment 1, the region of the two-dimensional material layer 1 corresponding to the channel region does not contact the first insulating film 3a. The size of the gap (GAP) is such that it generates an optical gating effect between the two-dimensional material layer 1 and the semiconductor layer 4.

[0275] The electromagnetic wave detector 100 may also include a connecting portion 7. The connecting portion 7 is disposed in the opening OP. The two-dimensional material layer 1 is electrically connected to the semiconductor layer 4 through the connecting portion 7. The material of the connecting portion 7 may be the same as the material of the semiconductor layer 4, the first electrode 2a, the second electrode 2b, or the control electrode 2c. Preferably, the height of the upper surface of the connecting portion 7 is the same as the height of the upper surface of the first electrode 2a.

[0276] The two-dimensional material layer 1 extends from the first electrode 2a to the connection portion 7. Alternatively, other structures can be used as long as a gap (GAP) is provided between the insulating film and the two-dimensional material layer 1.

[0277] In this embodiment, the second electrode 2b and the second insulating film 3b have the same properties as... Figure 8The second electrode 2b and the second insulating film 3b in Embodiment 2 shown have the same structure. Therefore, the second electrode 2b is directly connected to the semiconductor layer 4. The second insulating film 3b covers the control electrode 2c. In addition, the two-dimensional material layer 1 covers the semiconductor layer 4, the first insulating film 3a, and the second insulating film 3b.

[0278] Furthermore, the structure of the electromagnetic wave detector 100 in embodiment 12 can also be applied to other embodiments.

[0279] Next, the effects of this implementation method will be explained.

[0280] According to the electromagnetic wave detector 100 of embodiment 12, such as Figure 29 As shown, a gap (GAP) is provided between the first insulating film 3a and the two-dimensional material layer 1. Therefore, the effect of carrier scattering caused by the contact between the first insulating film 3a and the two-dimensional material layer 1 can be eliminated. As a result, the decrease in carrier mobility in the two-dimensional material layer 1 can be suppressed. Therefore, the sensitivity of the electromagnetic wave detector 100 can be improved. Furthermore, even with a gap (GAP) provided below the two-dimensional material layer 1, the optical gating effect can still function.

[0281] Implementation method 13.

[0282] Next, use Figure 30 and Figure 31 The structure of the electromagnetic wave detector 100 in Embodiment 13 will be described below. Unless otherwise specified, Embodiment 13 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures that are the same as those in Embodiment 3 described above, and the description will not be repeated.

[0283] like Figure 30 As shown, the electromagnetic wave detector 100 of this embodiment also includes a contact layer 8. The contact layer 8 is configured to contact at least any structure in the two-dimensional material layer 1 and the first electrode 2a. The contact layer 8 is configured to contact any structure in the two-dimensional material layer 1 and the first electrode 2a to supply holes or electrons (photocarriers) to the two-dimensional material layer 1. That is, the contact layer 8 is configured to dope the two-dimensional material layer 1 with holes or electrons.

[0284] exist Figure 30 The middle contact layer 8 is in contact with the first electrode 2a, such as Figure 31 As shown, the contact layer 8 may not be in contact with the first electrode 2a. Alternatively, the contact layer 8 may be configured to be in contact with either the two-dimensional material layer 1 or the first electrode 2a, but not with the other.

[0285] Although not shown, multiple contact layers 8 may be stacked on the two-dimensional material layer 1. The multiple contact layers 8 may be formed between the first electrode 2a and the semiconductor layer 4 in the two-dimensional material layer 1. The materials of the multiple contact layers 8 may be the same or different.

[0286] The material of contact layer 8 is, for example, a positive photoresist. The positive photoresist is a composition containing a photosensitizer having a quinone diazotization group and a phenolic resin. Alternatively, the material of contact layer 8 can be, for example, a material having polar groups. More specifically, the material of contact layer 8 can be, as an example, a material having electron-withdrawing groups, which is an example of a material having polar groups. Materials having electron-withdrawing groups have the effect of reducing the electron density of the two-dimensional material layer 1. Alternatively, the material of contact layer 8 can be, for example, a material having electron-donating groups, which is an example of a material having polar groups. Materials having electron-donating groups have the effect of increasing the electron density of the two-dimensional material layer 1.

[0287] In addition, as long as polarity is generated by the polarization of charges in the molecular whole, the material of the contact layer 8 can be inorganic, organic, metal, semiconductor, insulator, two-dimensional material or any mixture of these materials.

[0288] When the material of contact layer 8 is inorganic, if the work function of contact layer 8 is greater than the work function of two-dimensional material layer 1, then two-dimensional material layer 1 is doped into p-type. When the material of contact layer 8 is inorganic, if the work function of contact layer 8 is less than the work function of two-dimensional material layer 1, then two-dimensional material layer 1 is doped into n-type. When the material of contact layer 8 is organic, organic materials do not have a defined work function. Therefore, it is preferable to determine the polar groups of the material of contact layer 8 based on the polarity of the organic molecules constituting contact layer 8, thereby determining whether two-dimensional material layer 1 is doped into n-type or p-type.

[0289] Furthermore, for example, when a positive photoresist is used as the contact layer 8, the area in the two-dimensional material layer 1 where the photoresist is formed using a photolithography process is a p-type two-dimensional material layer area. Therefore, the formation process of a mask that contacts the surface of the two-dimensional material layer 1 is unnecessary. As a result, damage to the two-dimensional material layer 1 due to the mask formation process can be suppressed. Additionally, the manufacturing method can be simplified.

[0290] Furthermore, the material of contact layer 8 can be a material that undergoes a polarity change due to electromagnetic wave irradiation. By generating a polarity change in contact layer 8, electrons or holes generated during the polarity change are supplied to the two-dimensional material layer 1. Therefore, electrons or holes are doped into the portion of the two-dimensional material layer 1 that is in contact with contact layer 8. Thus, even after contact layer 8 is removed, the portion of the two-dimensional material layer 1 that was in contact with contact layer 8 remains doped with electrons or holes. Therefore, when using a material that generates a polarity change as the material of contact layer 8, contact layer 8 can be removed from the two-dimensional material layer 1 after the polarity change occurs. Compared to the case where contact layer 8 is provided, the area of ​​the opening portion of the two-dimensional material layer 1 is increased. Therefore, the detection sensitivity of the electromagnetic wave detector 100 can be improved. Furthermore, polarity change refers to the phenomenon of a polar group undergoing a chemical change, such as an electron-withdrawing group becoming an electron-donating group, or an electron-donating group becoming an electron-withdrawing group, or a polar group becoming a non-polar group, or a non-polar group becoming a polar group, etc.

[0291] By selecting a material that produces a polarity change at the detection wavelength as the material of the contact layer 8, a polarity change occurs in the contact layer 8 only when irradiated with an electromagnetic wave of the detection wavelength. Therefore, doping of the two-dimensional material layer 1 occurs only when irradiated with an electromagnetic wave of the detection wavelength. As a result, the photocurrent flowing into the two-dimensional material layer 1 can be increased.

[0292] Furthermore, the material of the contact layer 8 can be a material that undergoes a redox reaction when electromagnetic waves are irradiated onto the contact layer 8. This allows electrons or holes generated during the redox reaction in the contact layer 8 to be doped into the two-dimensional material layer 1.

[0293] Preferably, the contact layer 8 is thin enough to enable photoelectric conversion when electromagnetic waves irradiate the two-dimensional material layer 1. On the other hand, it is preferable that the contact layer 8 is formed to a thickness sufficient to allow charge carriers to be doped from the contact layer 8 into the two-dimensional material layer 1.

[0294] The structure of the contact layer 8 can be determined as appropriate, as long as charge carriers such as molecules or electrons are supplied to the two-dimensional material layer 1. For example, the two-dimensional material layer 1 can be doped into the two-dimensional material layer 1 by immersing it in a solution and supplying charge carriers to the two-dimensional material layer 1 at the molecular level, without the need to form a solid contact layer 8 on the two-dimensional material layer 1.

[0295] Furthermore, the structure of the electromagnetic wave detector 100 in embodiment 13 can also be applied to other embodiments.

[0296] Next, the effects of this implementation method will be explained.

[0297] According to the electromagnetic wave detector 100 of embodiment 13, such as Figure 30 As shown, the contact layer 8 is configured to contact at least any structure in the two-dimensional material layer 1 and the first electrode 2a. The contact layer 8 is configured to supply holes or electrons to the two-dimensional material layer 1 through contact with at least any structure in the two-dimensional material layer 1 and the first electrode 2a. Therefore, the conductivity type of the two-dimensional material layer 1 can be set to n-type or p-type. Thus, even when photocarriers are doped from the first electrode 2a and the semiconductor layer 4 into the two-dimensional material layer 1, the conductivity type of the two-dimensional material layer 1 can be controlled. Therefore, the performance of the electromagnetic wave detector 100 can be improved.

[0298] The contact layer 8 can be configured to contact either the two-dimensional material layer 1 or the first electrode 2a, but not to contact the other. Figure 31 The electrode is configured to contact the two-dimensional material layer 1 but not the first electrode 2a. This creates a charge density gradient in the two-dimensional material layer 1, thereby increasing the mobility of the two-dimensional material layer 1. Consequently, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0299] Implementation method 14.

[0300] Next, use Figure 32 The structure of the electromagnetic wave detector 100 in Embodiment 14 is described below. Unless otherwise specified, Embodiment 14 has the same structure, manufacturing method, and effects as Embodiment 3 described above. Therefore, the same reference numerals are used for structures identical to those in Embodiment 3, and the description will not be repeated.

[0301] like Figure 32 As shown, the two-dimensional material layer 1 of this embodiment includes a turbostratic structure portion 1T. The turbostratic structure portion 1T is a structure formed by stacking multiple graphene layers in a state where the individual lattices of the graphene layers are mismatched. Furthermore, the two-dimensional material layer 1 may include the turbostratic structure portion 1T as part of the two-dimensional material layer 1, or the entire two-dimensional material layer 1 may be composed of the turbostratic structure portion 1T. In this embodiment, the material of the two-dimensional material layer 1 is laminated graphene.

[0302] The method for fabricating the disordered layer structure 1T can be determined as appropriate. For example, the disordered layer structure 1T can be formed by repeatedly transferring and stacking multiple layers of graphene using a single layer of graphene fabricated by CVD. Alternatively, ethanol or methane can be placed on graphene as a carbon source, and graphene can be grown using CVD to form the disordered layer structure 1T.

[0303] Furthermore, the structure of the electromagnetic wave detector 100 in embodiment 14 can also be applied to other embodiments.

[0304] Next, the effects of this implementation method will be explained.

[0305] According to the electromagnetic wave detector 100 of embodiment 14, such as Figure 32 As shown, the two-dimensional material layer 1 includes a disordered layer structure portion 1T. Therefore, the carrier mobility in the two-dimensional material layer 1 can be increased. Consequently, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0306] More specifically, ordinary stacked graphene excluding the disordered layer structure portion 1T is stacked in a state where the individual lattices of each graphene are matched. This state is called AB stacking. On the other hand, stacked graphene including the disordered layer structure portion 1T is formed as follows: Graphene produced by CVD is polycrystalline. Therefore, when graphene is further transferred multiple times on top of the graphene, or when graphene is further stacked using a substrate graphene as a core by CVD, the individual lattices of each graphene are stacked in a mismatched state. That is, the disordered layer structure portion 1T is formed in the graphene. The disordered layer structure graphene constituting the disordered layer structure portion 1T is less affected by interlayer interactions and has properties equivalent to monolayer graphene. Furthermore, the mobility of the two-dimensional material layer 1 is reduced due to the scattering of charge carriers in the insulating film serving as the substrate. However, in the disordered-layer structure portion 1T, the graphene in contact with the insulating film is affected by carrier scattering, but the upper graphene layer stacked in a disordered structure on this graphene is less affected by carrier scattering from the insulating film of the substrate. Furthermore, in the disordered-layer structure of graphene, the conductivity is also improved due to less influence from interlayer interactions. Based on the above, carrier mobility is improved in the disordered-layer structure of graphene. As a result, the sensitivity of the electromagnetic wave detector 100 can be improved.

[0307] Implementation method 15.

[0308] Next, the structure of the electromagnetic wave detector 100 in Embodiment 15 will be described. Except for the materials of the first insulating film 3a, the second insulating film 3b, the semiconductor layer 4, and the contact layer 8, the electromagnetic wave detector 100 of this embodiment has the same... Figure 30 The electromagnetic wave detector 100 of Embodiment 13 shown has the same structure. Unless otherwise specified, Embodiment 15 has the same structure, manufacturing method, and effects as Embodiment 13 described above. Therefore, the same reference numerals are used for structures that are the same as those in Embodiment 13 described above, and the description will not be repeated.

[0309] The electromagnetic wave detector 100 of this embodiment includes a contact layer 8. The material of at least one of the first insulating film 3a, the second insulating film 3b, the semiconductor layer 4, and the contact layer 8 in this embodiment is a material that applies a potential change to the two-dimensional material layer 1 by changing its properties due to electromagnetic wave irradiation.

[0310] The materials that exert a potential change on the two-dimensional material layer 1 by altering their properties upon exposure to electromagnetic waves are, for example, strong dielectric materials and rare earth oxides in the first insulating film 3a and the second insulating film 3b. The materials that exert a potential change on the two-dimensional material layer 1 by altering their properties upon exposure to electromagnetic waves in the semiconductor layer 4 are, for example, the aforementioned semiconductor materials, pn junction materials, structures formed by bonding metals and semiconductors, structures formed by bonding metals, insulators, and semiconductor bonding materials, and perovskites. The materials that exert a potential change on the two-dimensional material layer 1 by altering their properties upon exposure to electromagnetic waves in the contact layer 8 are, for example, quantum dots, liquid crystal materials, fullerenes, and perovskites.

[0311] For example, when using a strong dielectric material that exhibits a polarization effect (pyroelectric effect) caused by electromagnetic waves, a polarization change occurs in the strong dielectric material due to the electromagnetic waves irradiating it. This results in a potential change in the two-dimensional material layer 1.

[0312] Furthermore, although an example has been described of applying a material that alters the properties of the two-dimensional material layer 1 by being irradiated with electromagnetic waves to induce a potential change in the two-dimensional material layer 1, to the first insulating film 3a, the second insulating film 3b, the semiconductor layer 4, and the contact layer 8, it is sufficient that the material is applied to at least one of the aforementioned components. For example, when a material that alters the properties of the two-dimensional material layer 1 by being irradiated with electromagnetic waves is applied to the contact layer 8, the contact layer 8 does not necessarily have to be in direct contact with the two-dimensional material layer 1. For example, as long as a potential change is irradiated on the two-dimensional material layer 1, the contact layer 8 can be provided on the upper or lower surface of the two-dimensional material layer 1 with an insulating film (not shown) in between.

[0313] Furthermore, the structure of the electromagnetic wave detector 100 in embodiment 15 can also be applied to other embodiments.

[0314] Next, the effects of this implementation method will be explained.

[0315] According to the electromagnetic wave detector 100 of embodiment 15, such as Figure 30 As shown, at least one of the first insulating film 3a, the second insulating film 3b, the semiconductor layer 4, and the contact layer 8 is made of a material whose properties change due to being irradiated with electromagnetic waves, thereby applying a potential change to the two-dimensional material layer 1. Therefore, by irradiating at least one of the first insulating film 3a, the second insulating film 3b, the contact layer 8, and the semiconductor layer 4 with electromagnetic waves, the potential of the two-dimensional material layer 1 can be changed.

[0316] Implementation method 16.

[0317] Next, use Figure 33 and Figure 34 The structure of the electromagnetic wave detector assembly 200 in embodiment 16 will be explained.

[0318] like Figure 33 As shown, the electromagnetic wave detector assembly 200 of this embodiment includes multiple electromagnetic wave detectors 100 of embodiments 1 to 14 and embodiment 17, which will be described later. The multiple electromagnetic wave detectors 100 are arranged in at least any one of a first direction DR1 and a second direction DR2 intersecting the first direction DR1. In this embodiment, the multiple electromagnetic wave detectors 100 included in the electromagnetic wave detector assembly 200 are identical to each other.

[0319] If multiple electromagnetic wave detectors 100 each have their own semiconductor layer 4 (refer to...) Figure 1 If they are separated, then among the multiple electromagnetic wave detectors 100, one second electrode 2b (refer to...) Figure 1 ( ) can be used as a common electrode. This reduces the wiring in the electromagnetic wave detector assembly 200, thus improving its resolution. For example, by using semiconductor layer 4 (refer to...) Figure 1 The outer periphery of the electromagnetic wave detector 100 is provided with a trench structure to house the semiconductor layer 4 (see reference). Figure 1 They are separated from each other. Control electrode 2c can be shared with the first electrode 2a.

[0320] exist Figure 33 In the electromagnetic wave detector assembly 200 shown, four electromagnetic wave detectors 100 are configured in a 2×2 matrix, but the number of electromagnetic wave detectors 100 configured is not limited to this. Furthermore, in Figure 33 In the electromagnetic wave detector assembly 200 shown, multiple electromagnetic wave detectors 100 are arranged periodically in a two-dimensional manner, or the multiple electromagnetic wave detectors 100 can be arranged periodically along one direction. In addition, the spacing between adjacent electromagnetic wave detectors 100 can be equal or different.

[0321] In addition, such as Figure 34 As shown, the electromagnetic wave detector assembly 200 may include a readout circuit 93 configured to read out signals from the electromagnetic wave detector 100. The electromagnetic wave detector 100 may be disposed on the readout circuit 93. The readout form of the readout circuit 93 may be, for example, a CTIA (Capacitive Transimpedance Amplifier) ​​type. The readout circuit 93 may be other readout forms.

[0322] Additionally, the electromagnetic wave detector assembly 200 may include a bump 92 that electrically connects the electromagnetic wave detector 100 to the readout circuit 93. The configuration where the electromagnetic wave detector 100 and the readout circuit 93 are connected by the bump 92 is called a hybrid junction. Hybrid junctions are a common configuration in quantum infrared sensors. The bump 92 and the electromagnetic wave detector 100 are electrically connected by a pad 91 disposed on the control electrode 2c. The material of the bump 92 is, for example, a conductive material such as indium (Ib). The material of the pad 91 is a conductive material such as an aluminum-silicon (Al-Si) based alloy, nickel (Ni), or gold (Au).

[0323] Next, use Figure 35 The structure of a modified example of the electromagnetic wave detector assembly 200 of Embodiment 16 will be described below.

[0324] like Figure 35 As shown, the electromagnetic wave detector assembly 200 includes multiple electromagnetic wave detectors 101 to 104 that are different from each other. The different types of electromagnetic wave detectors 101 to 104 are configured in an array (matrix). Each of the multiple electromagnetic wave detectors 101 to 104 may have a different detection wavelength. Specifically, each of the multiple electromagnetic wave detectors 101 to 104 may have a different detection wavelength selectivity. Furthermore, each of the multiple electromagnetic wave detectors 101 to 104 is configured to detect electromagnetic waves with different polarizations.

[0325] Semiconductor layers 4 (refer to) constitute the semiconductor layers 4 of the multiple electromagnetic wave detectors 101-104. Figure 1 The semiconductor materials used in this electromagnetic wave detector assembly 200 can each have different detection wavelengths. For example, semiconductor materials with a detection wavelength of visible light and semiconductor materials with a detection wavelength of infrared light can be used. For example, when this electromagnetic wave detector assembly 200 is applied to an automotive sensor, it can be used as a visible light imaging camera during the day, and as an infrared camera at night. In this way, it is not necessary to use multiple cameras separately according to the detection wavelength of the electromagnetic waves.

[0326] Next, the effects of this implementation method will be explained.

[0327] According to the electromagnetic wave detector assembly 200 of embodiment 16, such as Figure 33 As shown, the electromagnetic wave detector assembly 200 has multiple electromagnetic wave detectors 100 according to embodiments 1 to 14. Therefore, by using each electromagnetic wave detector of the multiple electromagnetic wave detectors 100 as a detection element, the electromagnetic wave detector assembly 200 can function as an image sensor.

[0328] According to a variation of the electromagnetic wave detector assembly 200 of embodiment 16, such as Figure 35 As shown, each of the multiple electromagnetic wave detectors 101 to 104 has a different detection wavelength. Therefore, the electromagnetic wave detector assembly 200 is capable of detecting electromagnetic waves of at least two different wavelengths.

[0329] Therefore, the electromagnetic wave detector assembly 200, similar to an image sensor for the visible light range, can identify the wavelength of electromagnetic waves in any wavelength range, such as ultraviolet light, infrared light, terahertz waves, and radio waves. As a result, for example, it is possible to obtain a colorized image that represents wavelength differences as color differences.

[0330] Furthermore, the electromagnetic wave detector assembly 200 can be used as a position detection sensor capable of detecting the position of an object, even with a small number of pixels. Additionally, the electromagnetic wave detector assembly 200 can be used as an image sensor capable of detecting the intensity of electromagnetic waves at multiple wavelengths. Therefore, it is possible to detect multiple electromagnetic waves and obtain a colorized image without using the color filters conventionally required in CMOS (Complementary MOS) sensors.

[0331] Multiple electromagnetic wave detectors 101-104 are each configured to detect electromagnetic waves with different polarizations. This allows the electromagnetic wave detector assembly 200 to function as a polarization recognition image sensor. For example, by configuring multiple electromagnetic wave detectors 100 for each unit, with four pixels having detected polarization angles of 0°, 90°, 45°, and 135° as a unit, polarization imaging can be performed. Using a polarization recognition image sensor, for example, it is possible to identify artificial and natural objects, identify materials, identify multiple objects with the same temperature in the infrared wavelength range, identify boundaries between multiple objects, or improve equivalent resolution.

[0332] As described above, the electromagnetic wave detector assembly 200 is capable of detecting electromagnetic waves over a wide wavelength range. Furthermore, the electromagnetic wave detector assembly 200 is capable of detecting electromagnetic waves of different wavelengths.

[0333] Implementation method 17.

[0334] Next, use Figures 36-38 The structure of the electromagnetic wave detector 100 in Embodiment 17 will be described below. Unless otherwise specified, Embodiment 17 has the same structure and effects as Embodiment 1 described above. Therefore, the same reference numerals are used for structures that are the same as those in Embodiment 1 described above, and the description will not be repeated.

[0335] like Figure 36As shown, the two-dimensional material layer 1 of this embodiment includes a pattern that generates plasma resonance. In this embodiment, the pattern that generates plasma resonance is a periodic strip pattern.

[0336] Specifically, the two-dimensional material layer comprises a plurality of strips 15. The width d of each of the plurality of strips 15 is equal to that of each other. The width d of each of the plurality of strips 15 is a dimension along the short side direction of each of the plurality of strips 15.

[0337] In the two-dimensional material layer 1, the multiple strips 15 are arranged at equal intervals, with gaps between them. That is, the multiple strips 15 of the two-dimensional material layer 1 are arranged periodically. Furthermore, the period p of the multiple strips 15 is the sum of the width d of each of the multiple strips 15 and the interval between adjacent strips 15.

[0338] The plasma resonance wavelength is determined based on the width d of each of the plurality of strips 15, the period p of the plurality of strips 15, and the Fermi level of the two-dimensional material layer 1. Furthermore, the width d of each of the plurality of strips 15 has a relative relationship with the period p of the plurality of strips 15. For example, when the width d of each of the plurality of strips 15 is 40 nm, the period p of the plurality of strips 15 is 50 nm, and the chemical potential is 1.0 eV, the plasma resonance wavelength is 4 μm.

[0339] like Figure 37 As shown, the portion connected to the first electrode 2a of the two-dimensional material layer 1 may not be strip-shaped.

[0340] like Figure 38 As shown, each of the plurality of strip-shaped portions 15 may have a plurality of first strip-shaped portions 151 and a plurality of second strip-shaped portions 152. The first strip-shaped portions of the plurality of first strip-shaped portions 151 and the second strip-shaped portions of the plurality of second strip-shaped portions 152 are alternately arranged along the long side direction of the plurality of strip-shaped portions 15. The width of each of the plurality of second strip-shaped portions 152 is greater than the width of each of the plurality of first strip-shaped portions 151. Figure 38 In the top view, each of the plurality of first strip-shaped portions 151 and the plurality of second strip-shaped portions 152 is quadrilateral in shape. Therefore, a quadrilateral pattern is formed in the two-dimensional material layer 1. The two-dimensional material layer 1 has an asymmetrical shape with respect to both the long and short sides of the plurality of strip-shaped portions 15. In other words, the two-dimensional material layer 1 is asymmetrical in two independent directions within the plane. Although not shown, the shapes of the plurality of second strip-shaped portions 152 can be circles, ellipses, squares, rectangles, etc. Furthermore, for ease of explanation, in... Figure 38 Control electrode 2c (reference) Figure 1 (Not shown in the diagram)

[0341] Next, the effects of this implementation method will be explained.

[0342] According to the electromagnetic wave detector 100 of embodiment 17, such as Figure 36 As shown, the two-dimensional material layer contains a pattern that generates plasmon resonance. The plasmon resonance wavelength is determined based on the width d of each of the plurality of strips 15, the period p of the plurality of strips 15, and the Fermi level of the two-dimensional material layer 1. Therefore, the electromagnetic wave detector 100 can selectively absorb light irradiating the electromagnetic wave detector 100 by utilizing resonant absorption according to the plasmon resonance wavelength. In addition, the electromagnetic wave detector 100 can enhance and absorb light irradiating the electromagnetic wave detector 100 by utilizing resonant absorption according to the plasmon resonance wavelength. Therefore, when light with the plasmon resonance wavelength irradiates the electromagnetic wave detector 100, the electric field on the two-dimensional material layer 1 is enhanced. As a result, the photoelectric conversion efficiency in the semiconductor layer 4 in contact with the two-dimensional material layer 1 is enhanced. Therefore, the sensitivity of the electromagnetic wave detector 100 can be selectively enhanced at the resonance wavelength.

[0343] The plasma resonance wavelength can be fixed by adjusting the width d and period p of the multiple strips 15. Furthermore, by adjusting the chemical potential of the two-dimensional material layer 1 using control electrodes, the plasma resonance wavelength can be electrically varied. Therefore, the aforementioned selective detection wavelength can be electrically controlled.

[0344] like Figure 38 As shown, each of the plurality of strip-shaped portions 15 may have a plurality of first strip-shaped portions 151 and a plurality of second strip-shaped portions 152. The width of each of the plurality of second strip-shaped portions 152 is greater than the width of each of the plurality of first strip-shaped portions 151. In this case, the shape of the two-dimensional material layer 1 has an asymmetric shape with respect to the long side direction and the short side direction of the plurality of strip-shaped portions 15. Due to the asymmetry of the two-dimensional material layer 1, asymmetry is also generated in the plasma resonance. Therefore, polarization can be selectively detected. When polarization can be selectively detected, the electromagnetic wave detector 100 can be applied to polarization imaging, etc.

[0345] It should be understood that the embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of this disclosure is shown not by the foregoing description but by the claims, and is intended to include all modifications in the same sense and scope as the claims.

Claims

1. An electromagnetic wave detector, comprising: Semiconductor layer; A first insulating film is disposed on the semiconductor layer and has an opening formed thereon; The first electrode is disposed on the first insulating film; A two-dimensional material layer, including a first region and a second region, extends from the opening to the first insulating film and is electrically connected to the first electrode. The first region is electrically connected to the semiconductor layer at the opening, and the second region is connected to the semiconductor layer between the first electrode and the opening, separated by the first insulating film, thereby generating an optical gating effect. The second electrode is electrically connected to the semiconductor layer; The second insulating film is in contact with the two-dimensional material layer; as well as The control electrode is connected to the two-dimensional material layer via the second insulating film. The two-dimensional material layer includes any material selected from the group consisting of graphene, transition metal dichalcogenides, black phosphorus, silicene, graphene nanoribbons, and borophene.

2. The electromagnetic wave detector according to claim 1, wherein, The second insulating film and the semiconductor layer sandwich the two-dimensional material layer. The control electrode is sandwiched between the two-dimensional material layer and the second insulating film.

3. An electromagnetic wave detector, comprising: Semiconductor layer; A first insulating film is disposed on the semiconductor layer and has an opening formed thereon; A two-dimensional material layer is electrically connected to the semiconductor layer at the opening and extends from the opening to the first insulating film; The first electrode is electrically connected to the two-dimensional material layer; The second electrode is electrically connected to the semiconductor layer; The second insulating film is in contact with the two-dimensional material layer; as well as The control electrode is connected to the two-dimensional material layer via the second insulating film. The control electrode and the second electrode sandwich the semiconductor layer. The second insulating film covers the control electrode. The two-dimensional material layer covers the semiconductor layer, the first insulating film, and the second insulating film. The two-dimensional material layer includes any material selected from the group consisting of graphene, transition metal dichalcogenides, black phosphorus, silicene, graphene nanoribbons, and borophene.

4. The electromagnetic wave detector according to claim 1 or 3, wherein, The configuration is such that the voltage difference between the first electrode and the second electrode changes.

5. The electromagnetic wave detector according to claim 1 or 3, wherein, The configuration involves applying a voltage to the two-dimensional material layer using the control electrode to change the Fermi level of the two-dimensional material layer.

6. The electromagnetic wave detector according to claim 1 or 3, wherein, The control electrode is made of a material that generates surface plasmon resonance.

7. The electromagnetic wave detector according to claim 1 or 3, wherein, The control electrode includes multiple control electrode sections. Among the plurality of control electrode portions, adjacent control electrode portions are arranged such that they are spaced apart from each other to generate surface plasmon resonance in each of the plurality of control electrode portions.

8. The electromagnetic wave detector according to claim 7, wherein, The two-dimensional material layer includes a first portion directly connected to the semiconductor layer. The plurality of control electrode sections include a first control electrode section. The first control electrode is connected to the first part through the second insulating film.

9. The electromagnetic wave detector according to claim 7, wherein, The two-dimensional material layer includes a second portion disposed on the first insulating film. The plurality of control electrode sections include a second control electrode section. The second control electrode is connected to the second part through the second insulating film.

10. The electromagnetic wave detector according to claim 1 or 3, wherein, The two-dimensional material layer includes a first end and a second end opposite to the first end. The first electrode includes a first side portion and a second side portion, the second side portion and the first side portion sandwiching the opening portion. The first end is directly connected to the first side. The second end is directly connected to the second side.

11. The electromagnetic wave detector according to claim 1 or 3, wherein, The two-dimensional material layer includes a first end and a second end opposite to the first end. The first end is directly connected to the first electrode. The second end is disposed away from the first electrode.

12. The electromagnetic wave detector according to claim 1 or 3, wherein, It also has a buffer layer. The buffer layer is sandwiched between the semiconductor layer and the two-dimensional material layer.

13. The electromagnetic wave detector according to claim 12, wherein, The buffer layer has a thickness capable of forming a tunnel current between the semiconductor layer and the two-dimensional material layer.

14. The electromagnetic wave detector according to claim 1 or 3, wherein, It also has the ability to connect to conductors. The two-dimensional material layer is electrically connected to the semiconductor layer through the connecting conductor.

15. The electromagnetic wave detector according to claim 1 or 3, wherein, The semiconductor layer includes a first semiconductor portion and a second semiconductor portion, wherein the second semiconductor portion has a different conductivity type than the first semiconductor portion. The first semiconductor portion is bonded to the second semiconductor portion.

16. The electromagnetic wave detector according to claim 15, wherein, The second semiconductor portion has a different absorption wavelength than the first semiconductor portion.

17. The electromagnetic wave detector according to claim 1 or 3, wherein, The opening includes multiple opening sections that are spaced apart from each other. The two-dimensional material layer is connected to the semiconductor layer at each of the plurality of openings.

18. The electromagnetic wave detector according to claim 1 or 3, wherein, The first insulating film includes a tapered portion. The tapered portion is configured such that its thickness varies as it moves closer to the opening from the first electrode.

19. An electromagnetic wave detector, comprising: Semiconductor layer; A first insulating film is disposed on the semiconductor layer and has an opening formed thereon; A two-dimensional material layer is electrically connected to the semiconductor layer at the opening and extends from the opening to the first insulating film; The first electrode is electrically connected to the two-dimensional material layer; The second electrode is electrically connected to the semiconductor layer; The second insulating film is in contact with the two-dimensional material layer; as well as The control electrode is connected to the two-dimensional material layer via the second insulating film. A gap is provided between the first insulating film and the two-dimensional material layer. The two-dimensional material layer includes any material selected from the group consisting of graphene, transition metal dichalcogenides, black phosphorus, silicene, graphene nanoribbons, and borophene.

20. The electromagnetic wave detector according to any one of claims 1, 3, and 19, wherein, It also has a contact layer. The contact layer is configured to contact any structure in the two-dimensional material layer and the first electrode.

21. The electromagnetic wave detector according to any one of claims 1, 3, and 19, wherein, The two-dimensional material layer includes a disordered layer structure.

22. The electromagnetic wave detector according to any one of claims 1, 3, and 19, wherein, The two-dimensional material layer includes a pattern that enables plasma resonance.

23. An electromagnetic wave detector assembly, wherein, It possesses an electromagnetic wave detector as described in any one of claims 1 to 22, The plurality of electromagnetic wave detectors are arranged in at least any one of a first direction and a second direction intersecting the first direction.

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