Resonant tunneling devices and methods for detecting their physical properties

Abstract

A resonant tunneling device and a method for detecting physical properties using the same. A resonant tunneling device includes: a first two-dimensional semiconductor layer comprising a first two-dimensional semiconductor material; a first insulating layer on the first two-dimensional semiconductor layer; and a second two-dimensional semiconductor layer on the first insulating layer and comprising a second two-dimensional semiconductor material of the same kind as the first two-dimensional semiconductor material.

Description

Technical Field

[0001] This disclosure relates to resonant tunneling devices comprising one or more two-dimensional semiconductor materials and methods for detecting physical properties using the resonant tunneling device. Background Technology

[0002] The negative differential resistance (NDR) effect is the phenomenon that an increase in the voltage applied to a device results in a decrease in the current flowing through it. The NDR effect is generally found in bulk materials with nonlinear electrical properties and has applications in various fields such as amplifiers, electronic oscillators, digital-to-analog converters, switching circuits, and memories. Recently, the NDR effect has also been observed in resonant tunneling devices fabricated by bonding two-dimensional materials. Summary of the Invention

[0003] A resonant tunneling device comprising two-dimensional semiconductor materials and a method for detecting physical properties using the resonant tunneling device are provided.

[0004] According to some example embodiments, a resonant tunneling device may include: a first two-dimensional semiconductor layer comprising a first two-dimensional semiconductor material; a first insulating layer on the first two-dimensional semiconductor layer; and a second two-dimensional semiconductor layer on the first insulating layer, the second two-dimensional semiconductor layer comprising a second two-dimensional semiconductor material of the same kind as the first two-dimensional semiconductor material. The lattices of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material may be aligned with each other.

[0005] The first two-dimensional semiconductor material and the second two-dimensional semiconductor material may each include transition metal dichalcogenides (TMD).

[0006] TMD can be represented by Equation 1.

[0007] M 1-a M' a X 2(1-b) X' 2b ...<Equation 1>

[0008] In Equation 1, M and M' are different transition metal elements, X and X' are different chalcogen elements, and 0 ≤ a < 1, 0 ≤ b < 1.

[0009] The different transition metal elements may each include at least one of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Tc, Re, Co, Rh, Ir, Ni, Pd, Pt, Zn, or Sn, and the different chalcogen elements may each include at least one of S, Se, or Te.

[0010] The first insulating layer may include a two-dimensional insulating material or an oxide material.

[0011] The resonant tunneling device may also include a first electrode electrically connected to a first two-dimensional semiconductor layer and a second electrode electrically connected to a second two-dimensional semiconductor layer.

[0012] The resonant tunneling device may also include a substrate, wherein a first two-dimensional semiconductor layer is on the substrate.

[0013] The substrate may include an insulating material.

[0014] The resonant tunneling device may further include: a second insulating layer, wherein the first two-dimensional semiconductor layer is on the second insulating layer; and a substrate, wherein the second insulating layer is on the substrate and includes a conductive material.

[0015] The substrate can be used as the gate electrode, and the second insulating layer can be used as the gate insulating layer.

[0016] The resonant tunneling device may also include a graphene layer on at least one of a first two-dimensional semiconductor layer or a second two-dimensional semiconductor layer.

[0017] Resonant tunneling devices can be configured to detect one or more physical properties of a first two-dimensional semiconductor material and a second two-dimensional semiconductor material based on the negative differential resistance (NDR) effect.

[0018] The physical properties may include electronic structure, band gap, or quantum capacitance.

[0019] Resonant tunneling devices can be configured to detect temperature, wavelength of light, or intensity of light based on the NDR effect.

[0020] According to some example embodiments, a method is provided for detecting physical properties using a resonant tunneling device, the resonant tunneling device comprising: a first two-dimensional semiconductor layer comprising a first two-dimensional semiconductor material; a first insulating layer on the first two-dimensional semiconductor layer; and a second two-dimensional semiconductor layer on the first insulating layer and comprising a second two-dimensional semiconductor material of the same kind as the first two-dimensional semiconductor material, wherein the lattices of the first two-dimensional semiconductor material and the lattices of the second two-dimensional semiconductor material are aligned with each other, the method may include causing the resonant tunneling device to detect one or more physical properties of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material based on the negative differential resistance (NDR) effect.

[0021] The physical properties may include electronic structure, band gap, or quantum capacitance.

[0022] The physical characteristic may be a bandgap, which can be detected using the NDR effect generated based on the gate voltage in the resonant tunneling device.

[0023] According to some example embodiments, a method is provided for detecting physical properties using a resonant tunneling device, the resonant tunneling device comprising: a first two-dimensional semiconductor layer including a first two-dimensional semiconductor material; a first insulating layer on the first two-dimensional semiconductor layer; and a second two-dimensional semiconductor layer provided on the first insulating layer and including a second two-dimensional semiconductor material of the same kind as the first two-dimensional semiconductor material, wherein the lattices of the first two-dimensional semiconductor material and the lattices of the second two-dimensional semiconductor material are aligned with each other, the method may include causing the resonant tunneling device to detect one or more of temperature, wavelength of light incident on the resonant tunneling device, or intensity of light incident on the resonant tunneling device based on the negative differential resistance (NDR) effect.

[0024] This temperature can be detected using the NDR effect generated based on the temperature in the resonant tunneling device.

[0025] The wavelength or intensity of light can be detected using the NDR effect produced by light incident on a resonant tunneling device.

[0026] According to some example embodiments, a resonant tunneling device may include: a first two-dimensional semiconductor layer including a first two-dimensional semiconductor material; a first insulating layer on the first two-dimensional semiconductor layer; and a second two-dimensional semiconductor layer on the first insulating layer, the second two-dimensional semiconductor layer including a second two-dimensional semiconductor material of the same kind as the first two-dimensional semiconductor material.

[0027] The lattices of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material can be aligned with each other.

[0028] The first two-dimensional semiconductor material and the second two-dimensional semiconductor material may each include transition metal dichalcogenides (TMD).

[0029] TMD can be represented by Equation 1.

[0030] M 1-a M' a X 2(1-b) X' 2b ...<Equation 1>

[0031] In Equation 1, M and M' are different transition metal elements, X and X' are different chalcogen elements, and 0 ≤ a < 1, 0 ≤ b < 1.

[0032] The different transition metal elements may each include at least one of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Tc, Re, Co, Rh, Ir, Ni, Pd, Pt, Zn, or Sn, and the different chalcogen elements may each include at least one of S, Se, or Te.

[0033] The first insulating layer may include a two-dimensional insulating material or an oxide material.

[0034] The resonant tunneling device may also include a first electrode electrically connected to a first two-dimensional semiconductor layer and a second electrode electrically connected to a second two-dimensional semiconductor layer.

[0035] The resonant tunneling device may also include a substrate, wherein a first two-dimensional semiconductor layer is on the substrate.

[0036] The substrate may include an insulating material.

[0037] The resonant tunneling device may further include: a second insulating layer, wherein the first two-dimensional semiconductor layer is on the second insulating layer; and a substrate, wherein the second insulating layer is on the substrate and includes a conductive material.

[0038] The substrate can be used as the gate electrode, and the second insulating layer can be used as the gate insulating layer.

[0039] The resonant tunneling device may also include a graphene layer on at least one of a first two-dimensional semiconductor layer or a second two-dimensional semiconductor layer.

[0040] A system may include a resonant tunneling device, a power supply, and processing circuitry configured to control the application of a voltage to at least one of a first two-dimensional semiconductor layer or a second two-dimensional semiconductor layer of the resonant tunneling device, such that the resonant tunneling device performs at least one of the following: detecting one or more physical properties of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material based on the negative differential resistance (NDR) effect; or detecting one or more of temperature, wavelength of light incident on the resonant tunneling device, or intensity of light incident on the resonant tunneling device based on the negative differential resistance (NDR) effect. Attached Figure Description

[0041] These and / or other aspects will become apparent and more readily understood from the following description of some exemplary embodiments in conjunction with the accompanying drawings, in which:

[0042] Figure 1 A resonant tunneling device according to some example embodiments is shown;

[0043] Figure 2A This is a schematic top view of the misalignment between the lattice of the first two-dimensional semiconductor material and the lattice of the second two-dimensional semiconductor material;

[0044] Figure 2B It is a schematic top view of the state in which the lattices of the first two-dimensional semiconductor material and the lattices of the second two-dimensional semiconductor material are aligned with each other;

[0045] Figure 3A , Figure 3B , Figure 3C and Figure 3D The resonant tunneling and NDR effects in a resonant tunneling device according to some example embodiments are illustrated, depending on the voltage applied between the first and second electrodes.

[0046] Figure 4 The voltage-current characteristic curves of a typical resonant tunneling device relative to the gate voltage are shown.

[0047] Figure 5 The voltage-current characteristics of a resonant tunneling device relative to the gate voltage are shown according to some example embodiments.

[0048] Figure 6 Voltage-current characteristic curves of a resonant tunneling device relative to temperature are shown according to some example embodiments;

[0049] Figure 7 The voltage-current characteristics of a resonant tunneling device relative to the power of incident light are shown according to some example embodiments.

[0050] Figure 8 The response characteristics of a resonant tunneling device relative to incident light are shown according to some example embodiments;

[0051] Figure 9 The external quantum efficiency of a resonant tunneling device relative to incident light is shown according to some example embodiments;

[0052] Figure 10 A resonant tunneling device according to some example embodiments is shown;

[0053] Figure 11 A resonant tunneling device according to some example embodiments is shown;

[0054] Figure 12 A resonant tunneling device according to some example embodiments is shown;

[0055] Figure 13 A resonant tunneling device according to some example embodiments is shown;

[0056] Figure 14 and Figure 15 This is a flowchart illustrating a method for operating a resonant tunneling device according to some example embodiments; and

[0057] Figure 16 A schematic diagram of a system according to some example embodiments is shown, which is configured to control and monitor the voltage applied to the various elements of a resonant tunneling device. Detailed Implementation

[0058] Referring now to exemplary embodiments, some of which are shown in the accompanying drawings, wherein the same reference numerals refer to the same elements throughout. In this regard, some exemplary embodiments may have different forms and should not be construed as limited to the description set forth herein. Therefore, only some exemplary embodiments are described below with reference to the accompanying drawings to illustrate aspects of this specification. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of” modify the entire column of elements without modifying individual elements of that column when following a list of elements.

[0059] In the context of describing this disclosure (particularly in the context of the appended claims), the terms “a” and “the”, and similar pronouns, should be interpreted to encompass both the singular and the singular. Furthermore, all methods described herein may be performed in any suitable order unless otherwise indicated herein or clearly contradicted by the context. This disclosure is not limited to the described order of operations. The use of any and all examples or language provided herein (e.g., “such as”) is intended only to better illustrate this disclosure and does not constitute a limitation on its scope unless otherwise stated.

[0060] Figure 1 A resonant tunneling device 100 according to some example embodiments is shown. As used herein, a resonant tunneling device may be referred to as a "semiconductor device".

[0061] Reference Figure 1 The resonant tunneling device 100 may include a substrate 110, a first two-dimensional semiconductor layer 131, a first insulating layer 140, a second two-dimensional semiconductor layer 132, and a graphene layer 150 sequentially stacked on the substrate 110. In some example embodiments, the substrate 110 may be omitted.

[0062] It will be understood that, as described herein, an element “on” another element may be above or below said other element. Additionally, an element “on” another element may be directly on said other element such that the element is in direct contact with said other element, or may be indirectly on said other element such that the element is not in direct contact with said other element through one or more interposed spaces and / or structures.

[0063] The substrate 110 may include a conductive material, such as a conductive material. In some example embodiments, the substrate 110 may be used as a gate electrode.

[0064] Substrate 110 may include a semiconductor material. The semiconductor material may include, for example, a group IV semiconductor material or a semiconductor compound. As a specific example, a group IV semiconductor material may include Si, Ge, Sn, etc. Substrate 110 may include a metal. The metal may include at least one of, for example, Cu, Mo, Ni, Al, W, Ru, Co, Mn, Ti, Ta, Au, Hf, Zr, Zn, Y, Cr, or Gd. In some example embodiments, the materials of substrate 110 mentioned above are merely examples, and substrate 110 may include various other materials. In some example embodiments, substrate 110 may include an insulating material.

[0065] The second insulating layer 120 may be formed on the upper surface 110a of the substrate 110, such that the first two-dimensional semiconductor layer 131 is on the second insulating layer 120 and the second insulating layer 120 is on the substrate 110. The second insulating layer 120 may serve as a gate insulating layer. The second insulating layer 120 may include, for example, an oxide (“oxide material”) or a nitride (“nitride material”), but is not limited thereto. In some example embodiments, the second insulating layer 120 may be omitted from the resonant tunneling device 100.

[0066] On the upper surface 120a of the second insulating layer 120, a first two-dimensional semiconductor layer 131 comprising a first two-dimensional semiconductor material may be provided. It will be understood that the first two-dimensional semiconductor layer 131 is on the substrate 110. Here, a two-dimensional semiconductor material refers to a material having a two-dimensional crystal structure and semiconductor properties.

[0067] First-dimensional semiconductor materials can include, for example, transition metal dichalcogenides (TMDs). TMDs are two-dimensional materials with semiconductor properties and excellent electrical properties. Even when the thickness of a TMD is reduced to the nanometer scale, its properties do not change significantly, and TMDs have high mobility, thus making them suitable for various devices.

[0068] A TMD can comprise two chalcogenide atom layers with a two-dimensional hexagonal honeycomb structure, and a metal atom layer sandwiched between these two chalcogenide atom layers. A TMD can be represented by Equation 1 as shown below.

[0069] M 1-a M' a X 2(1-b) X' 2b ...<Equation 1>

[0070] In Equation 1, M and M' are different transition metal elements, X and X' are different chalcogen elements, 0 ≤ a < 1, and 0 ≤ b < 1.

[0071] Different transition metal elements M and M' may each include at least one different one selected from Ti, Zr, Hf, V, Nb, Ta, Mo, W, Tc, Re, Co, Rh, Ir, Ni, Pd, Pt, Zn, or Sn. Different chalcogenide elements X and X' may each include at least one different one selected from S, Se, or Te. However, chalcogenide elements are not limited to these.

[0072] The first insulating layer 140 may be formed on the upper surface 131a of the first two-dimensional semiconductor layer 131, such that the first insulating layer 140 is understood to be on the first two-dimensional semiconductor layer 131. The first insulating layer 140 may include, for example, a two-dimensional insulating material. Here, the two-dimensional insulating material means a material having a two-dimensional crystal structure and insulating properties. The two-dimensional insulating material may include, for example, hexagonal boron nitride (h-BN). In some exemplary embodiments, the two-dimensional insulating material is not limited thereto. In some exemplary embodiments, the first insulating layer 140 may include an insulating material different from the two-dimensional insulating material. For example, the first insulating layer 140 may include an oxide material (also simply referred to herein as "oxide"), etc.

[0073] A second two-dimensional semiconductor layer 132, including a second two-dimensional semiconductor material, can be formed on the upper surface 140a of the first insulating layer 140, such that the second two-dimensional semiconductor layer 132 is on the first insulating layer 140. Here, the second two-dimensional semiconductor material can be a material of the same kind as the first two-dimensional semiconductor material described above. It will be understood that a material "of the same kind" as another material can be a material of the same type, composition, category, etc., as the other material. For example, the second two-dimensional semiconductor material can include a TMD, such that the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 each include the aforementioned TMD, and thus the second two-dimensional semiconductor layer 132 includes a material of the same kind as the first two-dimensional semiconductor layer 131.

[0074] In some example embodiments, a second two-dimensional semiconductor material may be disposed on the first insulating layer 140 such that the lattices of the first two-dimensional semiconductor material in the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor material in the second two-dimensional semiconductor layer 132 are aligned with each other. In some example embodiments, the two individual lattices are "aligned" with each other, wherein the lattices are at least 90% aligned with each other. In some example embodiments, the lattices of the first two-dimensional semiconductor material in the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor material in the second two-dimensional semiconductor layer 132 are not aligned with each other (e.g., more than 10% misaligned).

[0075] Figure 2A The diagram illustrates a misaligned state between the lattice 131' of the first two-dimensional semiconductor material and the lattice 132' of the second two-dimensional semiconductor material. (Refer to...) Figure 2AThe lattice 132' of the second two-dimensional semiconductor material can be twisted at a certain angle with the lattice 131' of the first two-dimensional semiconductor material. In contrast, Figure 2B The diagram shows the state in which the lattice 131' of the first two-dimensional semiconductor material and the lattice 132' of the second two-dimensional semiconductor material are aligned with each other.

[0076] In some example embodiments, a first two-dimensional semiconductor layer 131 and a second two-dimensional semiconductor layer 132, comprising the same type of first two-dimensional semiconductor material and second two-dimensional semiconductor material, may be provided therebetween with a first insulating layer 140. Here, the lattice 131' of the first two-dimensional semiconductor material and the lattice 132' of the second two-dimensional semiconductor material can be aligned with each other. Here, the alignment of the lattice 131' of the first two-dimensional semiconductor material and the lattice 132' of the second two-dimensional semiconductor material can be performed using, for example, a transfer method.

[0077] By aligning the lattice 131' of the first two-dimensional semiconductor material with the lattice 132' of the second two-dimensional semiconductor material, a resonant tunneling device 100 in which resonant tunneling and negative differential resistance (NDR) effects are more clearly exhibited can be fabricated, as described later. Here, the NDR effect refers to the phenomenon that the current decreases as the voltage applied to the device increases.

[0078] A graphene layer 150, including graphene, may be provided on the upper surface 132a of the second two-dimensional semiconductor layer 132. Graphene is a material having a two-dimensional crystalline structure and conductive properties. Specifically, graphene is a material having a hexagonal honeycomb structure in which carbon atoms are two-dimensionally linked, and having a thickness at the atomic scale. Graphene possesses high electromobility, excellent thermal properties, chemical stability, and a wide surface area. In some example embodiments, the graphene layer 150 can facilitate the flow of electrons and holes by readily adjusting the chemical potential of the second electrode 172, which will be described later.

[0079] A first two-dimensional semiconductor layer 131 can be electrically connected to a first electrode 171, and a second two-dimensional semiconductor layer 132 can be electrically connected to a second electrode 172 via a graphene layer 150. For this purpose, a third insulating layer 160 can be formed to cover the exposed upper surfaces 131a of the first two-dimensional semiconductor layer 131 and 150a of the graphene layer 150. The first electrode 171 can be formed on the third insulating layer 160 to be connected to the first two-dimensional semiconductor layer 131 via a via 161-1 formed in the third insulating layer 160. The second electrode 172 can be provided on the third insulating layer 160 and connected to the graphene layer 150 via another via 161-2 formed in the third insulating layer 160. It will be understood that in some example embodiments, the third insulating layer 160 can be omitted from the resonant tunneling device 100.

[0080] The first electrode 171 can be a source electrode, and the second electrode 172 can be a drain electrode. The first electrode 171 and the second electrode 172 can comprise, for example, a metal with excellent conductivity. Here, the metal can include at least one of Cu, Mo, Ni, Al, W, Ru, Co, Mn, Ti, Ta, Au, Hf, Zr, Zn, Y, Cr, or Gd. However, the metal is not limited to these.

[0081] In some example implementations, the first electrode 171 and / or the second electrode 172 may be omitted from the resonant tunneling device 100.

[0082] Figure 3A , Figure 3B , Figure 3C and Figure 3D It shows Figure 1 The resonant tunneling device 100 shown, according to some exemplary embodiments, exhibits resonant tunneling and NDR effects based on the voltage applied between the first electrode 171 and the second electrode 172. Here, MoS2 is used as both the first and second two-dimensional semiconductor materials, and the lattices of MoS2 as the first and second two-dimensional semiconductor materials are arranged in alignment with each other. Furthermore, h-BN is used as the material for the first insulating layer 140 provided between the first and second two-dimensional semiconductor layers 131 and 132. Silicon and silicon oxide are used as the materials for the substrate 110 and the second insulating layer 120, respectively.

[0083] exist Figures 3A to 3D In the diagram, the energy band diagram of MoS2 as a first two-dimensional semiconductor material is shown to the left of h-BN, which is the material of the first insulating layer 140, and the energy band diagram of MoS2 as a second two-dimensional semiconductor material is shown to the right of h-BN. In this diagram, V g V represents a specific (or alternatively, predetermined) gate voltage applied to substrate 110. d This represents the voltage applied between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 (e.g., between the first electrode 171 and the second electrode 172). R This represents the resonant voltage at which resonant tunneling occurs.

[0084] Reference Figure 3A When the voltage applied between the first electrode 171 and the second electrode 172 is 0V, no current flows through the resonant tunneling device 100. (Refer to...) Figure 3BWhen a voltage is applied between the first electrode 171 and the second electrode 172, the charge densities of MoS2, which is a first two-dimensional semiconductor material, and MoS2, which is a second two-dimensional semiconductor material, can change, and a relative Fermi level difference can be formed. Next, as the voltage applied between the first electrode 171 and the second electrode 172 gradually increases, the current flowing through the resonant tunneling device 100 increases due to the tunneling effect.

[0085] Reference Figure 3C When the voltage applied between the first electrode 171 and the second electrode 172 increases to the resonant voltage V R When the energy bands of MoS2, the first two-dimensional semiconductor material, and MoS2, the second two-dimensional semiconductor material, are aligned with each other, the tunneling current is greatly increased, thus enabling resonant tunneling. This is because when the energy states of the first and second two-dimensional semiconductor materials are aligned with each other, quantum mechanical effects maximize the tunneling effect.

[0086] Reference Figure 3D When the voltage applied between the first electrode 171 and the second electrode 172 is greater than the resonant voltage V R At this time, the NDR effect occurs, in which the current flowing through the resonant tunneling device 100 decreases instead.

[0087] In some example implementations, because the lattice of MoS2 as a first two-dimensional semiconductor material and the lattice of MoS2 as a second two-dimensional semiconductor material are aligned with each other, the resonant tunneling and NDR effects can be more clearly manifested compared to when the lattices are misaligned.

[0088] Most two-dimensional semiconductor materials exhibit diverse energy distributions in k-space, making precise band alignment difficult to achieve without precise alignment between lattices. However, in some exemplary embodiments, because the lattices of MoS2 as a first two-dimensional semiconductor material and MoS2 as a second two-dimensional semiconductor material are aligned with each other, resonant tunneling and NDR effects can be more effectively manifested by achieving precise band alignment.

[0089] Because resonant tunneling and NDR effects generated by quantum mechanical effects are closely related to the electronic structure of materials, the resonant tunneling device 100 according to some exemplary embodiments can effectively detect material properties of two-dimensional semiconductor materials, such as electronic structure, band gap, or quantum capacitance, by using the resonant tunneling and NDR effects. Furthermore, the resonant tunneling device 100 according to some exemplary embodiments can effectively detect the temperature around it or the wavelength or intensity of light applied to it.

[0090] Figure 4The voltage-current characteristic curves of a typical resonant tunneling device relative to the gate voltage are shown. Here, except for the lattice misalignment of the first and second two-dimensional semiconductor materials, the typical resonant tunneling device has the characteristics of... Figure 1 The resonant tunneling device 100 shown has the same structure. MoS2 is used as the first two-dimensional semiconductor material and the second two-dimensional semiconductor material, and h-BN is used as the first insulating layer material provided between the first two-dimensional semiconductor layer and the second two-dimensional semiconductor layer. Silicon and silicon oxide are used as the substrate and the second insulating layer materials, respectively.

[0091] Reference Figure 4 In general resonant tunneling devices, resonant tunneling and NDR effects can be observed. However, unlike the resonant tunneling devices according to some example embodiments described later, it can be seen that in general resonant tunneling devices, the resonant voltage at which resonant tunneling occurs is constant even if the gate voltage applied to the substrate changes.

[0092] Figures 5 to 9 It is shown Figure 1 The experimental results shown illustrate the characteristics of a resonant tunneling device 100 according to some exemplary embodiments. In the resonant tunneling device 100 according to some exemplary embodiments, MoS2 is used as a first two-dimensional semiconductor material and a second two-dimensional semiconductor material, and the lattices of MoS2 as the first two-dimensional semiconductor material and the lattices of MoS2 as the second two-dimensional semiconductor material are aligned with each other. Furthermore, h-BN is used as the material for the first insulating layer 140 provided between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132. Silicon and silicon oxide are used as the materials for the substrate 110 and the second insulating layer 120, respectively.

[0093] Figure 5 The voltage-current characteristic curves of a resonant tunneling device 100 relative to the gate voltage are shown according to some example embodiments.

[0094] Reference Figure 5 In the resonant tunneling device 100 according to some example embodiments, since the lattices of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material are aligned with each other, precise alignment of the energy bands can be caused, and thus resonant tunneling and NDR effects can be clearly seen.

[0095] Furthermore, in the resonant tunneling device 100 according to some example embodiments, it can be seen that the resonant voltage, which is the voltage at which resonant tunneling occurs, changes according to the gate voltage. This is because the amount of charge induced in the first two-dimensional semiconductor material and the second two-dimensional semiconductor material changes according to the gate voltage, causing the resistance to change. Therefore, the effective voltage applied between the first two-dimensional semiconductor material and the second two-dimensional semiconductor material is changed by the voltage applied between the first electrode and the second electrode.

[0096] Therefore, if the resistance of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material is sufficiently reduced by sufficiently increasing the gate voltage, then because most of the voltage applied between the first electrode and the second electrode is applied to the h-BN insulating layer between the first two-dimensional semiconductor material and the second two-dimensional semiconductor material, the resonant voltage V that appears at this time is... R It can be considered to correspond to the band gap of MoS2 as a first two-dimensional semiconductor material and a second two-dimensional semiconductor material.

[0097] As described above, by using the NDR effect generated according to changes in gate voltage, the resonant tunneling device 100 according to some example embodiments can detect physical properties of two-dimensional semiconductor materials, such as electronic structure, band gap, quantum capacitance, etc. It will be understood that in some example embodiments, any of the example embodiments of the resonant tunneling device described herein can be configured to detect one or more physical properties of a first two-dimensional semiconductor material and a second two-dimensional semiconductor material, such as physical properties of two-dimensional semiconductor materials, such as electronic structure, band gap, quantum capacitance, etc., based on the negative differential resistance (NDR) effect generated according to changes in gate voltage.

[0098] Figure 6 Voltage-current characteristic curves of a resonant tunneling device 100 relative to temperature are shown according to some example embodiments.

[0099] Reference Figure 6 As can be seen, the NDR effect becomes more pronounced as the ambient temperature of the resonant tunneling device 100 increases. This is because the resistance of both the first and second two-dimensional semiconductor materials decreases with increasing temperature. It can be observed that the NDR effect becomes more pronounced towards room temperature.

[0100] As described above, the resonant tunneling device 100 according to some example embodiments can detect the ambient temperature of the resonant tunneling device 100 by using the NDR effect generated according to temperature changes. It will be understood that in some example embodiments, any of the example embodiments of the resonant tunneling device described herein can be configured to detect the temperature of the resonant tunneling device, such as the ambient temperature, based on the NDR effect generated according to temperature changes.

[0101] Figure 7 Voltage-current characteristic curves of a resonant tunneling device 100 relative to the power of incident light are shown according to some example embodiments. Here, a laser with a wavelength of 638 nm is used as the incident light.

[0102] Reference Figure 7 It can be seen that when light with a greater energy than the optical bandgap of MoS2, which is both a first and second two-dimensional semiconductor material, is incident on the resonant tunneling device 100, an NDR effect, which is not apparent in the dark state, is exhibited. Therefore, it can be seen that the resonant tunneling device 100 according to some exemplary embodiments can be implemented as a highly efficient photodetector capable of detecting the wavelength of incident light. It will be understood that in some exemplary embodiments, any of the exemplary embodiments of the resonant tunneling device described herein can be configured to detect the wavelength of incident light on the resonant tunneling device based on the NDR effect. Moreover, as... Figure 7 As shown, the resonant voltage that generates resonant tunneling varies very sensitively with the intensity of light. Therefore, the resonant tunneling device 100 according to some exemplary embodiments can be effectively used to detect the intensity of incident light. It will be understood that in some exemplary embodiments, any of the exemplary embodiments of the resonant tunneling device described herein can be configured to detect the intensity of incident light on the resonant tunneling device based on the NDR effect.

[0103] Figure 8 The response characteristics of a resonant tunneling device relative to incident light are shown according to some example embodiments. Figure 9 The external quantum efficiency of a resonant tunneling device relative to incident light is shown according to some example embodiments. Here, a laser with a wavelength of 638 nm is used as the incident light.

[0104] Reference Figure 8 and Figure 9 As can be seen, the resonant tunneling device according to some example embodiments has good response characteristics relative to incident light and good external quantum efficiency relative to incident light.

[0105] Figure 14 and Figure 15 This is a flowchart illustrating a method of operating a resonant tunneling device according to some example embodiments. It will be understood that references can be made regarding any example embodiment of the resonant tunneling device. Figure 14 and Figure 15 The described operation.

[0106] Reference Figure 14A method for detecting the physical properties of the first two-dimensional semiconductor material of the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor material of the second two-dimensional semiconductor layer 132 may include applying a specific gate voltage V at operation S1402. g The gate electrode of the resonant tunneling device is applied. In some example embodiments, refer to... Figure 1 The gate electrode can be a substrate 110, such that operation S1402 includes applying the gate voltage V g Apply to substrate 110.

[0107] At operation S1404, separate voltages can be applied to the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 via separate corresponding electrodes that are electrically connected (e.g., directly connected) to separate layers. These electrodes can be a first electrode 171 and a second electrode 172, respectively. The voltages applied via the separate electrodes 171 and 172 can be different, such that V d This represents the voltage applied between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132.

[0108] At operation S1406, the corresponding voltage applied to one or both of the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 can be adjusted to make the voltage V applied between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132... d The voltage is adjusted (e.g., increased in magnitude). Gate voltage V g It can be at voltage V d While being adjusted, it remains at a fixed value. Adjustment at operation S1406 may also include: making the voltage V... d Adjusted to at least satisfy the resonant voltage V R This causes resonant tunneling to occur in the resonant tunneling device relative to the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132. The adjustment at operation S1406 may further include adjusting the voltage V. d Adjusted to exceed the resonant voltage V R This results in the NDR effect, which causes the current flowing through the resonant tunneling device to decrease.

[0109] At operation S1408, one or more physical properties (e.g., electronic structure, band gap, or quantum capacitance) of the first and second two-dimensional semiconductor materials can be determined based on the results of the adjustment at operation S1406. Such processing may include, for example, identifying the local maximum tunneling current in a resonant tunneling device (which is the voltage V). d functions, such as Figure 4 (As shown) to determine the resonant voltage V achieved at operation S1406.R Such processing may include: determining the resonant voltage V R The resonant voltage value V is compared with one or more entries in a database. R This is associated with corresponding physical property values ​​(e.g., electronic structure, band gap, quantum capacitance, etc. of two-dimensional semiconductor materials). Such a database can be a lookup table (“LUT”) stored in a computer-readable storage medium and generated via well-known empirical methods.

[0110] Reference Figure 15 A method for detecting one or more of temperature, wavelength of light, or intensity of light relative to a resonant tunneling device comprising a first two-dimensional semiconductor layer 131 and a second two-dimensional semiconductor layer 132 may include applying a specific gate voltage V at operation S1502. g The gate electrode of the resonant tunneling device is applied. In some example embodiments, refer to... Figure 1 The gate electrode can be a substrate 110, such that operation S1502 includes applying the gate voltage V. g Apply to substrate 110.

[0111] At operation S1504, separate voltages can be applied to the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 via separate corresponding electrodes that are electrically connected (e.g., directly connected) to separate layers of the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132. These electrodes can be a first electrode 171 and a second electrode 172, respectively. The voltages applied via the separate electrodes 171 and 172 can be different, such that V d This represents the voltage applied between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132.

[0112] At operation S1506, the corresponding voltage applied to one or both of the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 can be adjusted to make the voltage V applied between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132... d The voltage is adjusted (e.g., increased in magnitude). Gate voltage V g It can be at voltage V d While being adjusted, it remains at a fixed value. The adjustment at operation S1506 can also include adjusting the voltage V. d Adjusted to at least satisfy the resonant voltage V R This causes resonant tunneling to occur in the resonant tunneling device relative to the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132. The adjustment at operation S1506 may also include adjusting the voltage V... d Adjusted to exceed the resonant voltage V RThis results in the NDR effect, which causes the current flowing through the resonant tunneling device to decrease.

[0113] At operation S1508, one or more of the following can be determined relative to the temperature of the resonant tunneling device, the wavelength of the incident light, or the intensity of the incident light, based on the result of the adjustment at operation S1506. Such processing may include, for example, based on identifying the local maximum tunneling current in the resonant tunneling device (which is the voltage V). d functions, such as Figure 4 (As shown) to determine the resonant voltage V achieved at operation S1506. R Such processing may include determining the resonant voltage V. R And / or the detected current via the resonant tunneling device is compared with one or more entries in a database that stores the resonant voltage value V. R And / or the detected current value (“magnitude”) is correlated with corresponding values ​​for the temperature of the resonant tunneling device, the wavelength of the incident light on the resonant tunneling device, and / or the intensity of the incident light on the resonant tunneling device, for example, as Figure 6-9 The associations shown. Such a database can be a lookup table (“LUT”) stored in a computer-readable storage medium and generated via well-known empirical methods.

[0114] Will understand, Figure 14 and Figure 15 One or more of the operations, including but not limited to generating and / or storing the aforementioned LUT, can be implemented by a computing device comprising: a memory storing a program of instructions; and a processor executing the program of instructions to perform and / or control... Figure 14 and Figure 15 One or more aspects of one or more operations shown (including controlling the voltage application to one or more portions of the resonant tunneling device, detecting the resonant tunneling current in the resonant tunneling device, etc.). This could be as follows: Figure 16 The computing device 2000 shown may include one or more instances of processing circuitry, such as: hardware including logic circuitry; hardware / software combinations such as a processor executing software; or combinations thereof. For example, the processing circuitry may more specifically include, but is not limited to, a central processing unit (CPU), an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field-programmable gate array (FPGA), a system-on-a-chip (SoC), a programmable logic unit, a microprocessor, an application-specific integrated circuit (ASIC), etc. In some example embodiments, the processing circuitry may include: a non-transitory computer-readable storage device, such as a solid-state drive (SSD), storing a program of instructions; and a processor configured to execute the instructions of the program to implement... Figure 14 and 15Some or all of the operations of one or more of the methods shown. The computing device may be electrically connected to one or more electrodes (including, for example, first electrode 171 and second electrode 172) and substrate 110, and the computing device may be configured to control the power supply to one or more electrodes to control the application and / or regulation of voltage to one or more electrodes. The computing device may be connected to one or more sensors electrically connected to one or more elements of the resonant tunneling device, including, for example, voltmeters and / or ammeters, such that the computing device may be configured to receive signals from said one or more sensors and process said signals to determine the voltage applied to one or more electrodes associated with the resonant tunneling device, the current flowing through at least a portion of the resonant tunneling device, any combination thereof, etc.

[0115] Figure 10 A resonant tunneling device 200 according to some example embodiments is shown.

[0116] Reference Figure 10 The resonant tunneling device 200 may include a substrate 110, a graphene layer 250, a first two-dimensional semiconductor layer 131, a first insulating layer 140, and a second two-dimensional semiconductor layer 132 sequentially stacked on the substrate 110.

[0117] The substrate 110 may include a conductive material. Here, the substrate 110 may serve as a gate electrode. The substrate 110 may include, for example, a semiconductor material or a metal. A second insulating layer 120 may be formed on the upper surface of the substrate 110. The second insulating layer 120 may serve as a gate insulating layer.

[0118] A graphene layer 250, including graphene, may be provided on the upper surface 120a of the second insulating layer 120. The graphene layer 250 can facilitate the flow of electrons and holes by easily adjusting the chemical potential of the first electrode 171, which will be described later.

[0119] A first two-dimensional semiconductor layer 131, comprising a first two-dimensional semiconductor material, may be provided on the upper surface 250a of the graphene layer 250. Here, the first two-dimensional semiconductor material may include, for example, a TMD.

[0120] A first insulating layer 140 may be formed on the upper surface 131a of the first two-dimensional semiconductor layer 131. The first insulating layer 140 may include a two-dimensional insulating material or oxide such as h-BN. A second two-dimensional semiconductor layer 132, including a second two-dimensional semiconductor material, may be formed on the upper surface 140a of the first insulating layer 140. Here, the second two-dimensional semiconductor material may be a material of the same kind as the first two-dimensional semiconductor material described above. For example, the second two-dimensional semiconductor material may include a TMD. Here, the second two-dimensional semiconductor material may be configured such that its lattice is aligned with the lattice of the first two-dimensional semiconductor material provided below it.

[0121] The first two-dimensional semiconductor layer 131 can be electrically connected to the first electrode 171 through the graphene layer 250, and the second two-dimensional semiconductor layer 132 can be electrically connected to the second electrode 172. The first electrode 171 can be provided to be connected to the graphene layer 250 through a via 161-1 formed in the third insulating layer 160, and the second electrode 172 can be provided to be connected to the second two-dimensional semiconductor layer 132 through another via 161-2 formed in the third insulating layer 160.

[0122] The first electrode 171 and the second electrode 172 can be the source electrode and the drain electrode, respectively. The first electrode 171 and the second electrode 172 can include, for example, a metal with excellent conductivity.

[0123] Figure 11 A resonant tunneling device 300 according to some example embodiments is shown.

[0124] Reference Figure 11 The resonant tunneling device 300 may include a substrate 110, a first graphene layer 351, a first two-dimensional semiconductor layer 131, a first insulating layer 140, a second two-dimensional semiconductor layer 132, and a second graphene layer 352 sequentially stacked on the substrate 110.

[0125] The substrate 110 may include a conductive material. Here, the substrate 110 can serve as a gate electrode. A second insulating layer 120 may be formed on the upper surface of the substrate 110. The second insulating layer 120 can serve as a gate insulating layer.

[0126] A first graphene layer 351, including graphene, may be provided on the upper surface 120a of the second insulating layer 120. A first two-dimensional semiconductor layer 131, including a first two-dimensional semiconductor material, may be provided on the upper surface 351a of the first graphene layer 351. Here, the first two-dimensional semiconductor material may include, for example, a TMD.

[0127] A first insulating layer 140 may be formed on the upper surface 131a of the first two-dimensional semiconductor layer 131. The first insulating layer 140 may include a two-dimensional insulating material or oxide such as h-BN. A second two-dimensional semiconductor layer 132, including a second two-dimensional semiconductor material, may be formed on the upper surface 140a of the first insulating layer 140. Here, the second two-dimensional semiconductor material may be a material of the same kind as the first two-dimensional semiconductor material described above. For example, the second two-dimensional semiconductor material may include a TMD. Here, the second two-dimensional semiconductor material may be configured such that its lattice is aligned with the lattice of the first two-dimensional semiconductor material provided below it.

[0128] A second graphene layer 352, including graphene, can be provided on the upper surface 132a of the second two-dimensional semiconductor layer 132. The first two-dimensional semiconductor layer 131 can be electrically connected to the first electrode 171 through the first graphene layer 351, and the second two-dimensional semiconductor layer 132 can be electrically connected to the second electrode 172 through the second graphene layer 352.

[0129] The first electrode 171 can be provided to be connected to the first graphene layer 351 through a via 161-1 formed in the third insulating layer 160, and the second electrode 172 can be provided to be connected to the second graphene layer 352 through another via 161-2 formed in the third insulating layer 160. The first electrode 171 and the second electrode 172 can be the source electrode and the drain electrode, respectively.

[0130] Figure 12 A resonant tunneling device 400 according to some example embodiments is shown.

[0131] Reference Figure 12 The resonant tunneling device 400 may include a substrate 110, a first two-dimensional semiconductor layer 131, a first insulating layer 140, and a second two-dimensional semiconductor layer 132 sequentially stacked on the substrate 110.

[0132] The substrate 110 may include a conductive material. Here, the substrate 110 can serve as a gate electrode. A second insulating layer 120 may be formed on the upper surface 110a of the substrate 110. The second insulating layer 120 can serve as a gate insulating layer.

[0133] A first two-dimensional semiconductor layer 131, comprising a first two-dimensional semiconductor material, may be provided on the upper surface 120a of the second insulating layer 120. Here, the first two-dimensional semiconductor material may include, for example, a TMD. A first insulating layer 140 may be formed on the upper surface 131a of the first two-dimensional semiconductor layer 131. The first insulating layer 140 may include a two-dimensional insulating material or oxide such as h-BN.

[0134] A second two-dimensional semiconductor layer 132, including a second two-dimensional semiconductor material, can be formed on the upper surface 140a of the first insulating layer 140. Here, the second two-dimensional semiconductor material can be a material of the same kind as the first two-dimensional semiconductor material described above. For example, the second two-dimensional semiconductor material can include a TMD. Here, the second two-dimensional semiconductor material can be configured such that its lattice is aligned with the lattice of the first two-dimensional semiconductor material provided below it.

[0135] The first two-dimensional semiconductor layer 131 can be electrically connected to the first electrode 171, and the second two-dimensional semiconductor layer 132 can be electrically connected to the second electrode 172. The first electrode 171 can be provided to be connected to the first two-dimensional semiconductor layer 131 through a via 161-1 formed in the third insulating layer 160, and the second electrode 172 can be provided to be connected to the second two-dimensional semiconductor layer 132 through another via 161-2 formed in the third insulating layer 160. The first electrode 171 and the second electrode 172 can be the source electrode and the drain electrode, respectively.

[0136] Figure 13 A resonant tunneling device 500 according to some example embodiments is shown.

[0137] Reference Figure 13 The resonant tunneling device 500 may include a substrate 510, a first two-dimensional semiconductor layer 131, a first insulating layer 140, a second two-dimensional semiconductor layer 132, and a graphene layer 150 sequentially stacked on the substrate 510.

[0138] The substrate 510 may include an insulating material. A first two-dimensional semiconductor layer 131, including a first two-dimensional semiconductor material, may be provided on the upper surface of the substrate 510. Here, the first two-dimensional semiconductor material may include, for example, a TMD. A first insulating layer 140 may be formed on the upper surface 131a of the first two-dimensional semiconductor layer 131. The first insulating layer 140 may include a two-dimensional insulating material or oxide such as h-BN.

[0139] A second two-dimensional semiconductor layer 132, including a second two-dimensional semiconductor material, can be formed on the upper surface 140a of the first insulating layer 140. Here, the second two-dimensional semiconductor material can be a material of the same kind as the first two-dimensional semiconductor material described above. For example, the second two-dimensional semiconductor material can include a TMD. Here, the second two-dimensional semiconductor material can be configured such that its lattice is aligned with the lattice of the first two-dimensional semiconductor material provided below it.

[0140] A graphene layer 150, including graphene, may be provided on the upper surface 132a of the second two-dimensional semiconductor layer 132. A first two-dimensional semiconductor layer 131 may be electrically connected to a first electrode 171, and the second two-dimensional semiconductor layer 132 may be electrically connected to a second electrode 172 via the graphene layer 150. The first electrode 171 may be provided to be connected to the first two-dimensional semiconductor layer 131 via a via 161-1 formed in the third insulating layer 160, and the second electrode 172 may be provided to be connected to the graphene layer 150 via another via 161-2 formed in the third insulating layer 160. The first electrode 171 and the second electrode 172 may comprise, for example, a metal with excellent conductivity.

[0141] at the same time, Figure 13An example is shown where a graphene layer 150 is provided on a second two-dimensional semiconductor layer 132. However, the graphene layer 150 is not limited thereto; it may be provided on a first two-dimensional semiconductor layer 131, or on each of the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132. To reiterate, refer to... Figure 1 , Figure 10 and Figure 11 The graphene layer may be (e.g., directly on) at least one of the first two-dimensional semiconductor layer 131 or the second two-dimensional semiconductor layer 132. Moreover, the graphene layer 150 may be omitted.

[0142] According to the resonant tunneling device described above based on some example embodiments, the lattices of the stacked two-dimensional semiconductor materials can be aligned with each other, which can induce precise alignment of the energy bands, thereby clearly demonstrating the resonant tunneling and NDR effects.

[0143] Reference Figure 1 , Figure 10 , Figure 11 and Figure 12 In some example embodiments, the resonant tunneling devices 100, 200, 300 and 400 described herein may omit one or more elements, including one or more of the substrate 110, the second insulating layer 120, the third insulating layer 160, the first electrode 171, the second electrode 172, the graphene layer 150, the graphene layer 250, the first graphene layer 351, the second graphene layer 352, and any combination thereof.

[0144] Figure 16 A schematic diagram of a system 3000 according to some example embodiments is shown, which is configured to control and monitor the voltage application to the various elements of a resonant tunneling device. As used herein, the system 3000 may be referred to as an “assembly”.

[0145] Reference Figure 16 System 3000 includes a computing device 2000 (which may also be interchangeably referred to herein as an electronic device), a power supply 2100, and a resonant tunneling device 100. It will be understood that the resonant tunneling device of system 3000 may be replaced by a resonant tunneling device according to any of the exemplary embodiments. Figure 16 The resonant tunneling device 100 shown is shown.

[0146] First, referring to computing device 2000, computing device 2000 may include processing circuitry 2020 (also referred to herein as processor) connected together via bus 2010 communication ground and / or electrical ground, memory 2030, power supply device 2040 and communication interface 2050.

[0147] The computing device 2000 may be included in one or more of a wide variety of electronic devices, including, for example, mobile phones, digital cameras, sensor devices, etc. In some example embodiments, the computing device 2000 may include one or more of a server, mobile device, personal computer (PC), tablet computer, laptop computer, netbook, or some combination thereof. Mobile devices may include mobile phones, smartphones, personal digital assistants (PDAs), or some combination thereof.

[0148] System 3000 may include one or more of a wide variety of electronic devices. Such electronic devices may include, for example, mobile phones, digital cameras, sensor devices, servers, mobile devices, personal computers (PCs), tablet computers, laptop computers, netbooks, vehicles, autonomous vehicles, or some combination thereof.

[0149] The memory 2030, processing circuit 2020, power supply 2040 and communication interface 2050 can communicate with each other via bus 2010.

[0150] The communication interface 2050 can communicate data to and / or from external devices using various communication protocols. In some example implementations, the communication interface can be connected to electronic wires (e.g., wiring) and can be configured to receive and process electrical signals from one or more external devices.

[0151] like Figure 16 As shown, the processing circuit 2020 can execute programs and control one or more aspects of the system 3000 via the communication interface 2050. The program code executed by the processing circuit 2020 can be stored in the memory 2030.

[0152] Memory 2030 can store information. Memory 2030 can be volatile or non-volatile memory. Memory 2030 can be a non-transitory computer-readable storage medium. Memory can store computer-readable instructions that, when executed, cause the execution of one or more methods, functions, processes, etc., as described herein. In some example embodiments, processing circuitry 2020 can execute one or more computer-readable instructions stored in memory 2030.

[0153] In some example implementations, the communication interface 2050 may include a USB and / or HDMI interface. In some example implementations, the communication interface 2050 may include a wireless communication interface.

[0154] Still refer to Figure 16The power supply device 2100 includes a power source 2110 and one or more power distribution devices 2120, the power distribution devices 2120 being configured to distribute a portion of the power from the power source 2110 to individual electrodes coupled to individual portions of the resonant tunneling device 100. In some example embodiments, the power source 2110 may be any known type of power source including a connection to an external power source (e.g., mains power). In some example embodiments, such as in an embodiment where the power supply device 2100 is included in a computing device 2000, the power supply device 2100 may be a power supply device 2040 of the computing device 2000. In some example embodiments, each individual power distribution device 2120 may be any known device configured to regulate the power supply voltage applied to a particular electrode.

[0155] like Figure 16 As shown, system 3000 includes separate lines 2130-G, 2130-1, 2130-2 connecting power distribution equipment 2120 to individual electrodes, which are connected to individual elements of resonant tunneling device 100.

[0156] Line 2130-G connects one or more power distribution devices 2120 to the gate electrode associated with the resonant tunneling device 100, thereby causing the gate voltage V to... g It can be applied to the gate electrode. In some example embodiments, the resonant tunneling device 100 may include a substrate 110 serving as the gate electrode, such that line 2130-G connects one or more power distribution devices 2120 to the substrate 110, thereby causing the gate voltage V to be applied. g It can be applied to substrate 110. In some example embodiments, the resonant tunneling device 100 omits the gate electrode, so system 3000 may include gate electrode 2170, with line 2130-G connected from one or more power distribution devices 2120 to gate electrode 2170 to make gate voltage V g It can be applied to the gate electrode 2170.

[0157] Line 2130-1 connects one or more power distribution devices 2120 to the first electrode associated with the resonant tunneling device 100, thereby enabling a first voltage V1 to be applied to the first electrode. As further shown, line 2130-2 connects the second electrode associated with the resonant tunneling device 100 to electrical ground. The first electrode may be connected to a first two-dimensional semiconductor layer 131 of the resonant tunneling device 100, and the second electrode may be connected to a second two-dimensional semiconductor layer 132 of the resonant tunneling device 100, and is therefore described herein as representing the voltage V applied between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 (e.g., between the first electrode 171 and the second electrode 172). dIt can represent the difference between a first voltage V1 applied to the first electrode via line 2130-1 and a second voltage V2 connected to the second electrode via line 2130-2, wherein the second voltage V2 can be 0V.

[0158] In some example embodiments, the resonant tunneling device 100 may include a first electrode 171, such that a line 2130-1 connects one or more power distribution devices 2120 to the first electrode 171, thereby enabling a first voltage V1 to be applied to the first electrode 171. In some example embodiments, the resonant tunneling device 100 omits the first electrode 171, and thus the system 3000 may include a first electrode 2171, with the line 2130-1 connecting from the one or more power distribution devices 2120 to the first electrode 2171, so that the first voltage V1 can be applied to the first two-dimensional semiconductor layer 131 of the resonant tunneling device 100.

[0159] In some example embodiments, the resonant tunneling device 100 may include a second electrode 172, such that line 2130-2 connects to electrical ground on the second electrode 172, thereby enabling a second voltage V2 to be applied to the second electrode 172. In some example embodiments, the resonant tunneling device 100 omits the second electrode 172, and thus system 3000 may include a second electrode 2172, with line 2130-2 connected from electrical ground to the second electrode 2172, so that the second voltage V2 can be applied to the second two-dimensional semiconductor layer 132 of the resonant tunneling device 100.

[0160] Still refer to Figure 16 One or more voltage sensors 2200-G, 2200-1, 2200-2 can be electrically connected to individual corresponding lines of lines 2130-G, 2130-1, 2130-2 to detect corresponding voltages applied to individual corresponding gate electrodes, first electrodes, and / or second electrodes. As shown, computing device 2000 can be communicatively connected to one or more or all of the voltage sensors 2200-G, 2200-1, 2200-2, and can therefore be configured to determine the gate voltage V applied to the resonant tunneling device 100 based on processing data and / or signals generated by one or more of the voltage sensors 2200-G, 2200-1, 2200-2. g and voltage V d The voltage sensor can be any known type of voltage sensor. It will be understood that in some example embodiments, one or more or all of the voltage sensors 2200-G, 2200-1, and 2200-2 may be omitted from system 3000.

[0161] Still refer to Figure 16One or more current sensors 2300-G, 2300-1, 2300-2 can be electrically connected to individual corresponding lines of lines 2130-G, 2130-1, 2130-2 to detect corresponding currents flowing to or from individual corresponding gate electrodes, first electrodes, and / or second electrodes. As shown, computing device 2000 can be communicatively connected to one or more or all of current sensors 2300-G, 2300-1, 2300-2. Computing device 2000 can be configured to determine at least the current flowing between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 based on processing data and / or signals generated by one or more of current sensors 2300-G, 2300-1, 2300-2. The current sensors can be of any known type. It will be understood that in some example embodiments, one or more or all of current sensors 2300-G, 2300-1, 2300-2 can be omitted from system 3000.

[0162] It will be understood that some or all of the components of power supply device 2100, line 2130, voltage sensor 2200, current sensor 2300, and electrodes 2170, 2171, 2172 may be included in computing device 2000, and computing device may also include connectors configured (reversibly or irreversibly) to physically connect with resonant tunneling device 100 to establish system 3000 in Figure 16 The electrical connections are shown in the diagram.

[0163] The computing device 2000 can be configured, for example, to perform one or more control operations based on controlling one or more of the power distribution devices 2120 and power supplies 2110 to control the voltage application to one or more electrodes of the system, thereby adjustably controlling the gate voltage V. g And / or the voltage V between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 of the resonant tunneling device 100 d The application of voltage. The computing device 2000 can determine the gate voltage V based on processing data and / or signals transmitted by one or more voltage sensors 2200-G, 2200-1, 2200-2. g and / or voltage V d The value of any one of them (e.g., size).

[0164] The computing device 2000 may perform one or more determining operations based on processing data and / or signals transmitted by current sensors 2300-G, 2300-1, 2300-2 to determine the value (e.g., magnitude) of the current flowing through any of the lines 2130 and / or the current flowing through the resonant tunneling device 100 (including the current flowing between the first two-dimensional semiconductor layer 131 and the second two-dimensional semiconductor layer 132 of the resonant tunneling device 100).

[0165] The computing device 2000 can be configured to implement any of the methods described herein based on performing any of the foregoing control operations and determination operations, including... Figure 14-15 The examples shown in the text and / or referenced here are as follows: Figure 14-15 Any of the methods described herein. Any operation performed by computing device 2000 may be performed by processing circuitry 2020 based on executing instruction programs stored in memory 2030.

[0166] It will be understood that any of the methods described herein for detection performed by computing device 2000 may be referred to as processing circuit 2020 to cause resonant tunneling device 100 to perform the detection. For example, computing device 2000 may control the voltage applied to at least one of the first two-dimensional semiconductor layer 131 or the second two-dimensional semiconductor layer 132 of resonant tunneling device 100 based on performing any of the foregoing control and determination operations, which may be referred to as processing circuit 2020, to cause resonant tunneling device 100 to perform at least one of the following: detecting one or more physical properties of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material based on the negative differential resistance (NDR) effect; or detecting one or more of temperature, wavelength of light incident on resonant tunneling device, or intensity of light incident on resonant tunneling device based on the negative differential resistance (NDR) effect.

[0167] Because resonant tunneling and NDR effects generated by quantum mechanical effects are closely related to the electronic structure of materials, resonant tunneling devices according to some exemplary embodiments can effectively detect material properties of two-dimensional semiconductor materials, such as electronic structure, band gap, or quantum capacitance, by using resonant tunneling and NDR effects. Furthermore, resonant tunneling devices according to some exemplary embodiments can effectively detect the ambient temperature or the wavelength or intensity of light applied to them. While some exemplary embodiments have been described above, this disclosure is not limited thereto, and various modifications can be made by those skilled in the art.

[0168] It should be understood that the embodiments described herein are to be considered in a descriptive sense only and not for limiting purposes. The descriptions of features or aspects within each example embodiment should generally be considered applicable to other similar features or aspects in other example embodiments. While some example embodiments have been described with reference to the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope defined by the appended claims.

[0169] This application claims the benefit of Korean Patent Application No. 10-2019-0050721, filed on April 30, 2019, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety.

Claims

1. A resonant tunneling device, comprising: The first two-dimensional semiconductor layer includes a first two-dimensional semiconductor material; A first insulating layer on the first two-dimensional semiconductor layer; as well as A second two-dimensional semiconductor layer on the first insulating layer, the second two-dimensional semiconductor layer comprising a second two-dimensional semiconductor material of the same type as the first two-dimensional semiconductor material. The lattices of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material are aligned with each other, such that the first two-dimensional semiconductor material and the second two-dimensional semiconductor material have corresponding energy bands that are aligned with each other.

2. The resonant tunneling device according to claim 1, wherein... The first two-dimensional semiconductor material and the second two-dimensional semiconductor material each comprise the same transition metal dichalcogenide (TMD).

3. The resonant tunneling device according to claim 2, wherein... The same transition metal dichalcogenide compound is represented by Equation 1. M 1-a M' a X 2(1-b) X' 2b ...Equation 1 in, In Equation 1, M and M' are different transition metal elements, X and X' are different chalcogen elements, 0≤a<1, 0≤b<1.

4. The resonant tunneling device according to claim 3, wherein, In equation 1, The M and M' are different from each other, and each of the M and M' includes at least one of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Tc, Re, Co, Rh, Ir, Ni, Pd, Pt, Zn, or Sn. X and X' are different from each other, and each of X and X' includes at least one of S, Se or Te.

5. The resonant tunneling device according to claim 1, wherein... The first insulating layer comprises a two-dimensional insulating material or an oxide material.

6. The resonant tunneling device according to claim 1, further comprising: The first electrode is electrically connected to the first two-dimensional semiconductor layer; as well as The second electrode is electrically connected to the second two-dimensional semiconductor layer.

7. The resonant tunneling device according to claim 1, further comprising: A substrate, wherein the first two-dimensional semiconductor layer is on the substrate.

8. The resonant tunneling device according to claim 7, wherein The substrate includes an insulating material.

9. The resonant tunneling device according to claim 1, further comprising: A second insulating layer, wherein the first two-dimensional semiconductor layer is on the second insulating layer; as well as A substrate, wherein the second insulating layer is on the substrate and comprises a conductive material.

10. The resonant tunneling device according to claim 9, wherein... The substrate serves as the gate electrode, and the second insulating layer serves as the gate insulating layer.

11. The resonant tunneling device according to claim 1, further comprising: A graphene layer is disposed on at least one of the first two-dimensional semiconductor layer or the second two-dimensional semiconductor layer.

12. The resonant tunneling device according to claim 1, wherein... The resonant tunneling device is configured to detect one or more physical properties of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material based on the negative differential resistance (NDR) effect.

13. The resonant tunneling device according to claim 12, wherein... The physical properties include electronic structure, band gap, or quantum capacitance.

14. The resonant tunneling device according to claim 12, wherein... The resonant tunneling device is configured to detect temperature, wavelength of light, or intensity of light based on the negative differential resistance effect.

15. A method for detecting physical properties using a resonant tunneling device, the resonant tunneling device comprising a first two-dimensional semiconductor layer, a first insulating layer, and a second two-dimensional semiconductor layer, the first two-dimensional semiconductor layer comprising a first two-dimensional semiconductor material, the first insulating layer being on the first two-dimensional semiconductor layer, and the second two-dimensional semiconductor layer being on the first insulating layer and comprising a second two-dimensional semiconductor material of the same kind as the first two-dimensional semiconductor material, wherein the lattices of the first two-dimensional semiconductor material and the lattices of the second two-dimensional semiconductor material are aligned with each other, the method comprising: The resonant tunneling device is used to detect one or more physical properties of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material based on the negative differential resistance (NDR) effect. The first two-dimensional semiconductor material and the second two-dimensional semiconductor material have corresponding energy bands aligned with each other.

16. The method of claim 15, wherein The physical properties include electronic structure, band gap, or quantum capacitance.

17. The method of claim 16, wherein The physical property is a band gap, and The bandgap is detected using the negative differential resistance effect generated based on the gate voltage in the resonant tunneling device.

18. A resonant tunneling device, comprising: The first two-dimensional semiconductor layer includes a first two-dimensional semiconductor material; A first insulating layer on the first two-dimensional semiconductor layer; as well as A second two-dimensional semiconductor layer on the first insulating layer, the second two-dimensional semiconductor layer comprising a second two-dimensional semiconductor material of the same type as the first two-dimensional semiconductor material. The lattices of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material are aligned with each other, such that the first two-dimensional semiconductor material and the second two-dimensional semiconductor material have corresponding energy bands that are aligned with each other.

19. The resonant tunneling device according to claim 18, wherein... The first two-dimensional semiconductor material and the second two-dimensional semiconductor material each comprise the same transition metal dichalcogenide (TMD).

20. The resonant tunneling device according to claim 19, wherein... The same transition metal dichalcogenide compound is represented by Equation 1. M 1-a M' a X 2(1-b) X' 2b ...Equation 1 in, In Equation 1, M and M' are different transition metal elements, X and X' are different chalcogen elements, 0≤a<1, 0≤b<1.

21. The resonant tunneling device according to claim 20, wherein... The M and M' are different from each other, and each of the M and M' includes at least one of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Tc, Re, Co, Rh, Ir, Ni, Pd, Pt, Zn, or Sn. X and X' are different from each other, and each of X and X' includes at least one of S, Se or Te.

22. The resonant tunneling device according to claim 18, wherein... The first insulating layer comprises a two-dimensional insulating material or an oxide material.

23. The resonant tunneling device according to claim 18, further comprising: The first electrode is electrically connected to the first two-dimensional semiconductor layer; as well as The second electrode is electrically connected to the second two-dimensional semiconductor layer.

24. The resonant tunneling device according to claim 18, further comprising: A substrate, wherein the first two-dimensional semiconductor layer is on the substrate.

25. The resonant tunneling device according to claim 24, wherein... The substrate includes an insulating material.

26. The resonant tunneling device according to claim 18, further comprising: A second insulating layer, wherein the first two-dimensional semiconductor layer is on the second insulating layer; as well as A substrate, wherein the second insulating layer is on the substrate and comprises a conductive material.

27. The resonant tunneling device according to claim 26, wherein... The substrate serves as the gate electrode, and the second insulating layer serves as the gate insulating layer.

28. The resonant tunneling device according to claim 18, further comprising: A graphene layer is disposed on at least one of the first two-dimensional semiconductor layer or the second two-dimensional semiconductor layer.

29. A system comprising: The resonant tunneling device according to claim 18; Power supply equipment; as well as The processing circuit is configured as follows: Controlling the voltage applied to at least one of the first two-dimensional semiconductor layer or the second two-dimensional semiconductor layer of the resonant tunneling device to cause the resonant tunneling device to perform at least one of the following: Based on the negative differential resistance (NDR) effect, one or more physical properties of the first two-dimensional semiconductor material and the second two-dimensional semiconductor material are detected; or Based on the negative differential resistance (NDR) effect, one or more of the following can be detected: temperature, wavelength of light incident on the resonant tunneling device, or intensity of light incident on the resonant tunneling device.

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