Light receiving device and method for manufacturing light receiving device

Abstract

To provide a light receiving device and a method for manufacturing the light receiving device, capable of improving a light absorption amount.SOLUTION: A light receiving device includes: a first electrode: a first transition metal dichalcogenide layer which is formed on the first electrode and electrically connected to the first electrode; a second transition metal dichalcogenide layer which is formed on the first transition metal dichalcogenide layer and overlaps the first transition metal dichalcogenide layer in plan view; and a second electrode which is formed on the second transition metal dichalcogenide layer and overlaps the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer in plan view, and through which infrared rays pass. A laminate including the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer has a type II superlattice band structure. The light receiving device can be used, for example, in an infrared imaging apparatus.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a light receiving device and a method for manufacturing a light receiving device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a light-receiving device including a transition metal dichalcogenide layer has been known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-78280 A [Patent Document 2] US Patent Application Publication No. 2017 / 0338260 [Patent Document 3] US Patent Application Publication No. 2019 / 0131410 [Patent Document 4] Japanese Patent Publication No. 2022-87622 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been an increasing demand for improved light absorption.

[0005] An object of the present disclosure is to provide a light-receiving device and a method for manufacturing the light-receiving device that can improve the amount of light absorption. [Means for solving the problem]

[0006] According to one embodiment of the present disclosure, there is provided a light-receiving device comprising: a first electrode; a first transition metal dichalcogenide layer formed on the first electrode and electrically connected to the first electrode; a second transition metal dichalcogenide layer formed on the first transition metal dichalcogenide layer and overlapping the first transition metal dichalcogenide layer in a planar view; and a second electrode formed on the second transition metal dichalcogenide layer and overlapping the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer in a planar view, the second electrode being transparent to infrared light, wherein a stack including the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer has a type II superlattice band structure. [Effects of the Invention]

[0007] According to the present disclosure, the amount of light absorption can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view showing a light-receiving device according to a first embodiment. [Figure 2] 1 is a cross-sectional view showing a light-receiving device according to a first embodiment. [Figure 3] 1A to 1C are cross-sectional views (part 1) illustrating a method for manufacturing the light-receiving device according to the first embodiment. [Figure 4] 5A to 5C are cross-sectional views (part 2) illustrating the method for manufacturing the light-receiving device according to the first embodiment. [Figure 5] 5A to 5C are cross-sectional views (part 3) illustrating the method for manufacturing the light-receiving device according to the first embodiment. [Figure 6] 10A and 10B are cross-sectional views (part 4) illustrating the method for manufacturing the light-receiving device according to the first embodiment. [Figure 7] 5A to 5C are cross-sectional views illustrating the method for manufacturing the light-receiving device according to the first embodiment. [Figure 8] 10A and 10B are cross-sectional views (part 6) illustrating the method for manufacturing the light-receiving device according to the first embodiment. [Figure 9] 10A and 10B are cross-sectional views (part 7) illustrating the method for manufacturing the light-receiving device according to the first embodiment. [Figure 10] 8 is a cross-sectional view (part 8) illustrating the method for manufacturing the light-receiving device according to the first embodiment. [Figure 11] FIG. 10 is a cross-sectional view showing a light-receiving device according to a second embodiment. [Figure 12] FIG. 10 is a plan view showing a light-receiving device according to a third embodiment. [Figure 13] FIG. 10 is a cross-sectional view showing a light-receiving device according to a third embodiment. [Figure 14] FIG. 10 is a plan view showing a light-receiving device according to a fourth embodiment. [Figure 15] FIG. 10 is a cross-sectional view showing a light-receiving device according to a fourth embodiment. [Figure 16] 10A to 10C are cross-sectional views (part 1) illustrating a method for manufacturing a light-receiving device according to a fourth embodiment. [Figure 17] 10A and 10B are cross-sectional views (part 2) illustrating the method for manufacturing the light-receiving device according to the fourth embodiment. [Figure 18] 10A and 10B are cross-sectional views (part 3) illustrating the method for manufacturing the light-receiving device according to the fourth embodiment. [Figure 19] FIG. 10 is a plan view showing a light-receiving device according to a fifth embodiment. [Figure 20] FIG. 10 is a cross-sectional view (part 1) illustrating a light-receiving device according to a fifth embodiment. [Figure 21] FIG. 10 is a cross-sectional view (part 2) illustrating the light-receiving device according to the fifth embodiment. [Figure 22] FIG. 10 is a plan view showing a light-receiving device according to a sixth embodiment. [Figure 23] FIG. 10 is a cross-sectional view showing a light-receiving device according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Note that in this specification and drawings, components having substantially the same functional configurations may be denoted by the same reference numerals to avoid redundant description. In this specification and drawings, the X1-X2 direction, the Y1-Y2 direction, and the Z1-Z2 direction are defined as mutually orthogonal directions. The plane including the X1-X2 direction and the Y1-Y2 direction is defined as the XY plane, the plane including the Y1-Y2 direction and the Z1-Z2 direction is defined as the YZ plane, and the plane including the Z1-Z2 direction and the X1-X2 direction is defined as the ZX plane. For convenience, the Z1 direction is defined as the upward direction, and the Z2 direction is defined as the downward direction. Furthermore, in this disclosure, a planar view refers to viewing an object from the Z1 side.

[0010] (First embodiment) A first embodiment will be described. The first embodiment relates to a light-receiving device. FIG. 1 is a plan view showing the light-receiving device according to the first embodiment. FIG. 2 is a cross-sectional view showing the light-receiving device according to the first embodiment. FIG. 2 corresponds to a cross-sectional view taken along line II-II in FIG. 1.

[0011] As shown in Figures 1 and 2, the light-receiving device 1 of the first embodiment mainly includes a substrate 100, a first electrode 103, a second electrode 104, a transition metal dichalcogenide (TMDC) stack 110, an insulating layer 121, and an insulating layer 122.

[0012] The substrate 100 has an insulating upper surface (surface on the Z1 side). For example, the substrate 100 has a silicon substrate 101 and an insulating layer 102. The insulating layer 102 is provided on the silicon substrate 101. The silicon substrate 101 contains impurities and is conductive. The insulating layer 102 is, for example, a silicon oxide (SiO2) layer.

[0013] The first electrode 103 is provided on the insulating layer 102. The first electrode 103 is provided on a portion of the insulating layer 102. The first electrode 103 has, for example, a first graphene layer. The first graphene layer includes one or more graphenes stacked on top of each other. The first electrode 103 extends along the X1-X2 direction.

[0014] The insulating layer 121 is provided on the insulating layer 102 and around the first electrode 103. The insulating layer 121 includes, for example, an alumina layer. The thickness of the insulating layer 121 is, for example, about 5 nm.

[0015] The TMDC stack 110 is provided on the first electrode 103. The TMDC stack 110 is provided on a portion of the first electrode 103. In other words, another portion of the first electrode 103 is not covered by the TMDC stack 110. The TMDC stack 110 includes a first TMDC layer 111 and a second TMDC layer 112. The first TMDC layer 111 is provided on the first electrode 103. The Z2-side surface of the first TMDC layer 111 contacts the Z1-side surface of the first electrode 103. The second TMDC layer 112 is provided on the first TMDC layer 111. The Z2-side surface of the second TMDC layer 112 contacts the Z1-side surface of the first TMDC layer 111. In a planar view, the second TMDC layer 112 overlaps the first TMDC layer 111. In plan view, the outer edge of the first TMDC layer 111 and the outer edge of the second TMDC layer 112 overlap each other.

[0016] The first TMDC layer 111 and the second TMDC layer 112 are made of different materials. The first TMDC layer 111 includes one or more first TMDCs stacked on top of each other. The second TMDC layer 112 includes one or more second TMDCs stacked on top of each other. The TMDC stack 110 has a type-II superlattice band structure. For example, the first TMDC may be tungsten disulfide (WS2), molybdenum diselenide (MoSe2), or molybdenum disulfide (MoS2), and the second TMDC may be hafnium disulfide (HfS2), zirconium disulfide (ZrS2), or tin diselenide (SnSe2). The first TMDC may be HfS2, ZrS2, or SnSe2, and the second TMDC may be WS2, MoSe2, or MoS2.

[0017] The insulating layer 122 is provided on the insulating layer 121 and surrounds the TMDC stack 110. An opening is formed in the insulating layer 122, and the first electrode 103 is exposed through this opening. The insulating layer 122 includes, for example, an alumina layer. The thickness of the insulating layer 122 is, for example, approximately 10 nm.

[0018] The second electrode 104 is disposed on the TMDC stack 110 and the insulating layer 122. A portion of the insulating layer 122 is covered by the second electrode 104, and another portion of the insulating layer 122 is exposed from the second electrode 104. The Z2-side surface of the second electrode 104 contacts the Z1-side surface of the second TMDC layer 112. In a planar view, the second electrode 104 overlaps the TMDC stack 110. The second electrode 104 is made of a material that transmits infrared rays. The infrared transmittance of the second electrode 104 is, for example, 70% or more, preferably 80% or more, and more preferably 90% or more. The second electrode 104 includes, for example, a second graphene layer. The second graphene layer includes one or more graphenes stacked on top of each other. The thickness of the second electrode 104 is, for example, 5 nm or less, preferably 3 nm or less, and more preferably 2 nm or less. The second electrode 104 extends along the X1-X2 direction.

[0019] Next, a method for manufacturing the light receiving device 1 according to the first embodiment will be described. Figures 3 to 9 are cross-sectional views showing the method for manufacturing the light receiving device 1 according to the first embodiment.

[0020] First, as shown in FIG. 3, a substrate 100 is prepared. For example, a silicon oxide layer may be formed as the insulating layer 102 by oxidizing the Z1 side surface of a silicon substrate 101. A silicon substrate with a thermal oxide film may also be used as the substrate 100. Next, a first electrode 103 is provided on the insulating layer 102. The first electrode 103 can be provided, for example, by transferring a first graphene layer and processing its shape.

[0021] 4, an insulating layer 121 is formed on the insulating layer 102 so as to cover the first electrode 103. In forming the insulating layer 121, an alumina layer is formed by, for example, atomic layer deposition (ALD).

[0022] 5, the portion of the insulating layer 121 that covers the first electrode 103 is removed. The partial removal of the insulating layer 121 can be performed by, for example, wet etching using a mask.

[0023] 6, a first TMDC layer 111 is formed on the first electrode 103 and the insulating layer 121, and a second TMDC layer 112 is formed on the first TMDC layer 111. The first TMDC layer 111 and the second TMDC layer 112 can be formed by, for example, chemical vapor deposition (CVD). The first TMDC layer 111 and the second TMDC layer 112 may be formed separately and then transferred onto the first electrode 103 and the insulating layer 121.

[0024] 7, the TMDC stack 110 is processed to expose a portion of the insulating layer 121 and the first electrode 103 from the TMDC stack 110. A portion of the TMDC stack 110 may remain on the insulating layer 121.

[0025] 8, an insulating layer 122 is formed on the TMDC stack 110, the insulating layer 121, and the first electrode 103. In forming the insulating layer 122, an alumina layer is formed by, for example, the ALD method.

[0026] 9, the portions of insulating layer 122 covering TMDC stack 110 and first electrode 103 are removed. As a result, parts of TMDC stack 110 and first electrode 103 are exposed from insulating layer 122. The partial removal of insulating layer 122 can be performed by, for example, wet etching using a mask.

[0027] 10, a second electrode 104 is provided on the TMDC stack 110 and the insulating layer 121. The second electrode 104 may be provided so as to protrude from the TMDC stack 110 in a plan view and overlap the portion of the first electrode 103 that is exposed from the TMDC stack 110. The second electrode 104 can be provided by, for example, transferring a second graphene layer.

[0028] Next, the second electrode 104 is processed so that the portion of the first electrode 103 exposed from the TMDC stack 110 is also exposed from the second electrode 104 (see FIGS. 1 and 2).

[0029] In this manner, the light receiving device 1 according to the first embodiment can be manufactured.

[0030] In the light-receiving device 1, the second electrode 104 overlaps the first TMDC layer 111 and the second TMDC layer 112 in a planar view, but infrared light passes through the second electrode 104. Therefore, when infrared light is irradiated onto the light-receiving device 1 from above the second electrode 104, the infrared light passes through the second electrode 104 and enters the TMDC stack 110. Because the TMDC stack 110 has a type-II superlattice band structure, the TMDC stack 110 absorbs the infrared light through band-to-band transition, and a current corresponding to the amount of absorbed infrared light flows between the first electrode 103 and the second electrode 104. In the light-receiving device 1, the conductive silicon substrate 101 functions as a control electrode. That is, the light-receiving device 1 has a back-gate structure.

[0031] If infrared light cannot pass through the second electrode 104, it is possible to arrange the second electrode 104 so as not to interfere with infrared light absorption by the TMDC stack 110. However, in this case, a large area must be secured for the second electrode 104 in plan view, which increases the area of ​​the light-receiving device 1 in plan view. Compared to this embodiment, the amount of infrared light absorbed per unit area of ​​the light-receiving device 1 in plan view is lower. From the opposite perspective, this embodiment can improve the amount of infrared light absorbed.

[0032] The TMDC stack 110 can be formed by a deposition method such as CVD, etc. By using a deposition method, it is possible to easily form a large-area TMDC stack 110 compared to when it is provided by transfer.

[0033] Note that the material of the second electrode 104 does not have to be graphene as long as infrared rays can pass through the second electrode 104. For example, nanocarbon such as carbon nanotubes may be used, or a conductive TMDC such as niobium sulfide (NbS) may be used. Also, SiO2 doped with tungsten (W) may be used.

[0034] Furthermore, the first electrode 103 does not have to be transparent to infrared rays, and the material of the first electrode 103 does not have to be graphene. For example, the material of the first electrode 103 may be a metal. For example, the first electrode 103 may have a metal laminate of a titanium (Ti) film with a thickness of about 5 nm and a gold (Au) film thereon with a thickness of about 20 nm.

[0035] The insulating layers 121 and 122 may be made of, for example, hexagonal boron nitride (hBN), a two-dimensional material. The insulating layers 121 and 122 may include one or more layers of hBN stacked on top of each other.

[0036] (Second embodiment) A second embodiment will be described. The second embodiment differs from the first embodiment mainly in the configuration of the first electrode. Fig. 11 is a cross-sectional view showing a light-receiving device according to the second embodiment.

[0037] 11 , the light-receiving device 2 according to the second embodiment has a first electrode 203 instead of the first electrode 103, and does not have an insulating layer 121. The first electrode 203 is provided on the insulating layer 102 and is wider than the first electrode 103. The first electrode 203 has a first graphene layer, just like the first electrode 103. An insulating layer 122 is provided on the insulating layer 102 around the TMDC stack 110. In the light-receiving device 2, a portion of the first electrode 103 and a portion of the second electrode 104 overlap with each other, with the insulating layer 122 sandwiched therebetween.

[0038] Other configurations of the second embodiment are the same as those of the first embodiment. The second embodiment can also achieve the same effects as the first embodiment.

[0039] (Third embodiment) A third embodiment will now be described. The second embodiment differs from the first embodiment mainly in the configuration of the electrodes. FIG. 12 is a plan view showing a light-receiving device according to the third embodiment. FIG. 13 is a cross-sectional view showing a light-receiving device according to the third embodiment. FIG. 13 corresponds to a cross-sectional view taken along line XIII-XIII in FIG. 12.

[0040] As shown in FIGS. 12 and 13, the light receiving device 3 according to the third embodiment includes a control electrode 105, a metal electrode 133, a metal electrode 134, a metal electrode 135, and a conductive via 145 in addition to the components of the light receiving device 1.

[0041] The control electrode 105 is provided in the insulating layer 122. For example, the insulating layer 122 may have a two-layer structure, and the control electrode 105 may be provided by arranging the control electrode 105 between the two layers. The control electrode 105 is provided near the TMDC stack 110. The control electrode 105 has, for example, a graphene layer. The graphene layer includes one or more graphene layers stacked on top of each other. The control electrode 105 may include about two to four layers of graphene. The material of the control electrode 105 may be a metal.

[0042] A via hole is formed in the insulating layer 122, which is spaced apart from the TMDC stack 110 in plan view and reaches the control electrode 105, and a conductive via 145 is provided in the via hole. A metal electrode 135 is provided on the conductive via 145 and the insulating layer 122. The metal electrode 135 is in contact with the conductive via 145 and is electrically connected to the conductive via 145 and the control electrode 105.

[0043] The metal electrode 133 is provided on the first electrode 103 and the insulating layer 122. The metal electrode 133 is in contact with the first electrode 103 and is electrically connected to the first electrode 103. The metal electrode 134 is provided on the second electrode 104 and the insulating layer 122. The metal electrode 134 is in contact with the second electrode 104 and is electrically connected to the second electrode 104.

[0044] The conductive via 145 has, for example, a metal laminate of a Ti film with a thickness of about 5 nm and an Au film with a thickness of about 10 nm thereon. The thickness of the Au film may be approximately the same as the total thickness of the insulating layers 121 and 122. The material of the metal electrodes 133, 134, and 135 is not particularly limited, and may be, for example, Au, palladium (Pd), nickel (Ni), chromium (Cr), or Ti. The metal electrodes 133, 134, and 135 may include a laminate of these metals.

[0045] Other configurations of the third embodiment are similar to those of the first embodiment. The third embodiment also achieves the same effects as the first embodiment. Furthermore, since the control electrode 105 is provided, the state of the TMDC stack 110 can be controlled by the control electrode 105. If the distance between the control electrode 105 and the TMDC stack 110 is smaller than the distance between the silicon substrate 101 and the TMDC stack 110, it is easier to control the state of the TMDC stack 110.

[0046] The metal electrodes 133, 134, and 135 can be connected to an external circuit via, for example, bonding wires. Alternatively, the light-receiving device 3 may be flip-chip connected to an interposer or a printed wiring board via the metal electrodes 133, 134, and 135.

[0047] When the material of the control electrode 105 is a metal, the control electrode 105 may be thicker than when the control electrode 105 includes a graphene layer. In this case, the total thickness of the insulating layers 121 and 122 may be, for example, about 20 nm to 40 nm.

[0048] In the third embodiment, a first electrode 203 may be provided instead of the first electrode 103 as in the second embodiment.

[0049] (Fourth embodiment) A fourth embodiment will be described. The fourth embodiment differs from the first embodiment mainly in the configuration of the insulating layer. FIG. 14 is a plan view showing a light-receiving device according to the fourth embodiment. FIG. 15 is a cross-sectional view showing a light-receiving device according to the fourth embodiment. FIG. 15 corresponds to a cross-sectional view taken along line XV-XV in FIG. 14.

[0050] 14 and 15 , in the light-receiving device 4 according to the fourth embodiment, a portion of the insulating layer 121 is provided on the first electrode 103, and an opening 121A is formed in the insulating layer 121. The first electrode 103 is exposed through the opening 121A. The TMDC stack 110 is provided on the first electrode 103 within the opening 121A.

[0051] Other configurations of the fourth embodiment are the same as those of the first embodiment. The fourth embodiment can also achieve the same effects as those of the first embodiment.

[0052] Next, a method for manufacturing the light receiving device 4 according to the fourth embodiment will be described. Figures 16 to 18 are cross-sectional views showing the method for manufacturing the light receiving device 4 according to the fourth embodiment.

[0053] First, similarly to the first embodiment, processing up to the formation of the insulating layer 121 is performed (see FIG. 4). Next, as shown in FIG. 16, an opening 121A that exposes a part of the first electrode 103 is formed in the insulating layer 121. The opening 121A can be formed by, for example, wet etching using a mask.

[0054] 17, TMDC stack 110 is provided on first electrode 103 inside opening 121A. Subsequently, insulating layer 122 is formed on TMDC stack 110 and insulating layer 121.

[0055] 18, the portion of the insulating layer 122 that covers the TMDC stack 110 is removed. As a result, the TMDC stack 110 is exposed from the insulating layer 122.

[0056] Thereafter, similarly to the first embodiment, the processes from the formation of the second electrode 104 onwards are carried out.

[0057] In this manner, the light receiving device 4 according to the fourth embodiment can be manufactured.

[0058] In the fourth embodiment, a first electrode 203 may be provided instead of the first electrode 103 as in the second embodiment. Also, a control electrode 105 and the like may be provided as in the third embodiment.

[0059] (Fifth embodiment) A fifth embodiment will be described. The fifth embodiment differs from the fourth embodiment mainly in that a plurality of TMDC stacks or the like are provided. FIG. 19 is a plan view showing a light-receiving device according to the fifth embodiment. FIGS. 20 and 21 are cross-sectional views showing the light-receiving device according to the fifth embodiment. FIG. 20 corresponds to a cross-sectional view taken along line XX-XX in FIG. 19. FIG. 21 corresponds to a cross-sectional view taken along line XXI-XXI in FIG. 19.

[0060] As shown in FIG. 21, the light receiving device 5 according to the fifth embodiment includes a plurality of sets of first electrodes 103, second electrodes 104, TMDC stacks 110, metal electrodes 133, metal electrodes 134, and relay electrodes 153.

[0061] The first electrode 103 has an L-shaped planar shape. The first electrode 103 has a portion extending along the X1-X2 direction and a portion extending along the Y1-Y2 direction. The X1-side end of the portion extending along the X1-X2 direction and the Y2-side end of the portion extending along the Y1-Y2 direction are connected to each other.

[0062] A via hole is formed in the insulating layer 122, reaching a portion of the first electrode 103 extending along the Y1-Y2 direction away from the TMDC stack 110 in a plan view, and a conductive via 143 is provided in the via hole. A relay electrode 153 is provided on the conductive via 143 and the insulating layer 122. A metal electrode 133 is provided on the relay electrode 153 and the insulating layer 122. The metal electrode 133 is in contact with the relay electrode 153 and is electrically connected to the relay electrode 153, the conductive via 143, and the first electrode 103. The conductive via 143 has a metal laminate, for example, a Ti film having a thickness of approximately 5 nm and an Au film having a thickness of approximately 10 nm thereon. The thickness of the Au film may be approximately the same as the total thickness of the insulating layers 121 and 122. The relay electrode 153 has, for example, a graphene layer. The graphene layer includes one or more graphene layers stacked on top of each other.

[0063] As in the fourth embodiment, a TMDC stack 110 is provided on a portion of the first electrode 103 extending along the X1-X2 direction, and a second electrode 104 is provided on the TMDC stack 110. A metal electrode 134 is provided on the second electrode 104 and the insulating layer 122. The metal electrode 134 is in contact with the second electrode 104 and is electrically connected to the second electrode 104.

[0064] The metal electrodes 133 and 134 can be connected to an external circuit via, for example, bonding wires. Alternatively, the light-receiving device 5 may be flip-chip connected to an interposer or a printed wiring board via the metal electrodes 133 and 134.

[0065] Other configurations of the fifth embodiment are similar to those of the fourth embodiment. The fifth embodiment also achieves the same effects as the fourth embodiment. Furthermore, since the light-receiving device 5 has multiple TMDC stacks 110, it can be used as a line sensor. Furthermore, by arranging multiple TMDC stacks 110 not only in the X1-X2 direction but also in the Y1-Y2 direction, i.e., by arranging them two-dimensionally, two-dimensional images can be easily acquired. Furthermore, when forming an array, the multiple first electrodes 103, the multiple TMDC stacks 110, and the multiple second electrodes 104 can be formed simultaneously. Therefore, an increase in the number of processes required for arraying can be suppressed.

[0066] (Sixth embodiment) A sixth embodiment will be described. The sixth embodiment differs from the fourth embodiment mainly in the configuration of the electrodes. FIG. 22 is a plan view showing a light-receiving device according to the sixth embodiment. FIG. 23 is a cross-sectional view showing a light-receiving device according to the sixth embodiment. FIG. 23 corresponds to a cross-sectional view taken along line XXIII-XXIII in FIG. 22.

[0067] As shown in FIGS. 22 and 23, the light-receiving device 6 according to the sixth embodiment includes a control electrode 605, a metal electrode 135, and a conductive via 145 in addition to the components of the light-receiving device 4.

[0068] The control electrode 605 is provided in the insulating layer 122. The control electrode 605 can be provided, for example, between the insulating layer 121 and the insulating layer 122. The control electrode 605 is provided near the TMDC stack 110. The control electrode 605 has a ring-shaped planar shape that surrounds the TMDC stack 110. The control electrode 605 has, for example, a graphene layer. The graphene layer includes one or more graphene layers stacked on top of each other. The control electrode 605 may include about two to four layers of graphene. The material of the control electrode 605 may be metal.

[0069] A via hole is formed in the insulating layer 122, which is spaced apart from the TMDC stack 110 in plan view and reaches the control electrode 605, and a conductive via 145 is provided in the via hole. A metal electrode 135 is provided on the conductive via 145 and the insulating layer 122. The metal electrode 135 is in contact with the conductive via 145 and is electrically connected to the conductive via 145 and the control electrode 105.

[0070] Other configurations of the sixth embodiment are similar to those of the fourth embodiment. The sixth embodiment also achieves the same effects as the fourth embodiment. Furthermore, since the control electrode 605 is provided, the state of the TMDC stack 110 can be controlled by the control electrode 605. If the distance between the control electrode 605 and the TMDC stack 110 is smaller than the distance between the silicon substrate 101 and the TMDC stack 110, it is easier to control the state of the TMDC stack 110.

[0071] The light-receiving device 6 may further include metal electrodes 133 and 134 as in the third embodiment.

[0072] When the material of the control electrode 605 is a metal, the control electrode 605 may be thicker than when the graphene layer is included. In this case, the total thickness of the insulating layers 121 and 122 may be, for example, about 20 nm to 40 nm.

[0073] The light receiving device can be used, for example, in an infrared imaging device.

[0074] Although the preferred embodiments have been described in detail above, the present disclosure is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0075] Various aspects of the present disclosure are summarized below as appendices.

[0076] (Appendix 1) A first electrode; a first transition metal dichalcogenide layer formed on the first electrode and electrically connected to the first electrode; a second transition metal dichalcogenide layer formed on the first transition metal dichalcogenide layer and overlapping the first transition metal dichalcogenide layer in a plan view; a second electrode formed on the second transition metal dichalcogenide layer, overlapping the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer in a plan view, and transmitting infrared light; and A light-receiving device, wherein a stack including the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer has a type II superlattice band structure. (Appendix 2) 2. The light-receiving device according to claim 1, wherein the first transition metal dichalcogenide layer, the second transition metal dichalcogenide layer, and the second electrode overlap the first electrode in a planar view. (Appendix 3) 3. The light-receiving device according to claim 1, wherein the first electrode has a first graphene layer. (Appendix 4) 4. The light-receiving device according to claim 1, wherein the second electrode has a second graphene layer. (Appendix 5) a substrate; A light-receiving device described in any one of appendix 1 to 4, characterized in that multiple sets of the first transition metal dichalcogenide layer, the second transition metal dichalcogenide layer, the first electrode, and the second electrode are provided on the substrate. (Appendix 6) an insulating layer surrounding the laminate in the plan view; 6. The light-receiving device according to claim 1, wherein the second electrode is provided on the insulating layer. (Appendix 7) 7. The light-receiving device according to claim 6, wherein the first electrode is provided under the insulating layer. (Appendix 8) forming a first transition metal dichalcogenide layer on the first electrode; forming a second transition metal dichalcogenide layer on the first transition metal dichalcogenide layer so as to overlap the first transition metal dichalcogenide layer in a plan view; forming a second electrode on the second transition metal dichalcogenide layer, the second electrode overlapping the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer in a plan view and transmitting infrared light; and A method for manufacturing a light-receiving device, wherein a stack including the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer has a type II superlattice band structure. (Appendix 9) 9. The method for manufacturing a light-receiving device described in Appendix 8, wherein the first transition metal dichalcogenide layer, the second transition metal dichalcogenide layer, and the second electrode overlap the first electrode in a planar view. [Explanation of symbols]

[0077] 1, 2, 3, 4, 5, 6: Light receiving device 100: Substrate 103, 203: 1st electrode: 1st electrode 104:Second electrode 105, 605: Control electrode 110: Transition metal dichalcogenide stack 111: First transition metal dichalcogenide layer 112: Second transition metal dichalcogenide layer

Claims

1. A first electrode; a first transition metal dichalcogenide layer formed on the first electrode and electrically connected to the first electrode; a second transition metal dichalcogenide layer formed on the first transition metal dichalcogenide layer and overlapping the first transition metal dichalcogenide layer in a plan view; a second electrode formed on the second transition metal dichalcogenide layer, overlapping the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer in a plan view, and transmitting infrared light; and A light-receiving device, wherein a stack including the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer has a type II superlattice band structure.

2. 2 . The light-receiving device according to claim 1 , wherein the first transition metal dichalcogenide layer, the second transition metal dichalcogenide layer, and the second electrode overlap the first electrode in a plan view.

3. The light-receiving device according to claim 1 , wherein the first electrode comprises a first graphene layer.

4. The light-receiving device according to claim 1 , wherein the second electrode comprises a second graphene layer.

5. a substrate; 3. The light-receiving device according to claim 1, wherein a plurality of sets of the first transition metal dichalcogenide layer, the second transition metal dichalcogenide layer, the first electrode, and the second electrode are provided on the substrate.

6. forming a first transition metal dichalcogenide layer on the first electrode; forming a second transition metal dichalcogenide layer on the first transition metal dichalcogenide layer so as to overlap the first transition metal dichalcogenide layer in a plan view; forming a second electrode on the second transition metal dichalcogenide layer, the second electrode overlapping the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer in a plan view and transmitting infrared light; and A method for manufacturing a light-receiving device, wherein a stack including the first transition metal dichalcogenide layer and the second transition metal dichalcogenide layer has a type II superlattice band structure.

7. 7. The method for manufacturing a light-receiving device according to claim 6, wherein the first transition metal dichalcogenide layer, the second transition metal dichalcogenide layer, and the second electrode overlap the first electrode in a plan view.

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