CN116885032A - Waveguide integrated photodetector and preparation method thereof - Google Patents

Abstract

The invention discloses a waveguide integrated photoelectric detector and a preparation method thereof. The waveguide integrated photodetector includes a waveguide and a van der Waals heterojunction; the van der Waals heterojunction includes a p-type two-dimensional semiconductor layer disposed on one side of the waveguide, and a p-type two-dimensional semiconductor layer disposed on the back of the waveguide. An n-type two-dimensional semiconductor layer on one side of the waveguide. In the present invention, the flow of electrons and holes will form a sudden change in potential at the van der Waals heterojunction interface to generate a built-in electric field. The built-in electric field can serve as a potential barrier for free carrier movement in the device without light, reducing dark spots. current; at the same time, it can also speed up the separation of photogenerated carriers, improve the carrier extraction rate, and thereby improve the photoresponsivity and photoresponse rate.

Description

Waveguide integrated photodetector and preparation method thereof

Technical field

The invention relates to the technical field of optical communication devices, and in particular to a waveguide integrated photodetector and a preparation method thereof.

Background technique

In the field of optical communications, photodetectors are the core sensing component that converts optical signals into electrical signals. Its wavelength belongs to the near-infrared band (0.76-3.00μm), and there has been a lot of research on on-chip integrated optical circuits.

In order to meet the needs of the development of silicon-based optoelectronic integrated chips, there have been studies using 2D (2dimensional, two-dimensional) materials. 2D materials refer to materials with atomic thickness in one dimension. 2D materials have high mechanical flexibility and transparency. The surface It can be stacked arbitrarily without dangling bonds, has wide band gap coverage, high carrier mobility, and can be flexibly integrated. Therefore, it can meet the requirements of silicon photonic chips for wide spectrum, high performance, and integrated photodetectors. Therefore, on-chip integrated photodetectors working in different spectral ranges can be constructed by selecting different 2D materials. However, the optimization of the bandwidth, responsivity and linearity of the detector is still in its infancy; there are still questions about how to effectively suppress dark current, How to improve responsiveness and response rate and many other issues.

Contents of the invention

The main purpose of the present invention is to propose a waveguide integrated photodetector and a preparation method thereof, aiming to solve many problems in the existing technology such as how to effectively suppress dark current and how to improve the responsivity and response rate.

In order to achieve the above object, the present invention proposes a waveguide integrated photodetector, which includes a waveguide and a van der Waals heterojunction; the van der Waals heterojunction includes a p-type two-dimensional semiconductor layer disposed on one side of the waveguide, and a p-type two-dimensional semiconductor layer disposed on one side of the waveguide. The p-type two-dimensional semiconductor layer faces away from the n-type two-dimensional semiconductor layer on one side of the waveguide.

Optionally, the material of the p-type two-dimensional semiconductor layer includes black phosphorus; and/or the material of the n-type two-dimensional semiconductor layer includes one of MoTe ₂ , MoSe ₂ , and WSe ₂ .

Optionally, the thickness of the p-type two-dimensional semiconductor layer is 1 to 200 nm; and/or the thickness of the n-type two-dimensional semiconductor layer is 1 to 200 nm.

Optionally, the material of the waveguide includes one of silicon, silicon nitride, and lithium niobate; and/or, the waveguide includes a rectangular waveguide, a ridge waveguide, or a groove waveguide.

Optionally, the waveguide has a first side end and a second side end connected to the first side end, wherein one of the first side ends is used to receive incident light;

The van der Waals heterojunction is disposed beyond the waveguide on a peripheral side of the waveguide to form a first peripheral region located on the outer periphery of the waveguide;

The waveguide integrated photodetector also includes:

A substrate, the substrate is disposed on the other side of the waveguide, and the substrate is disposed beyond the waveguide on the peripheral side of the waveguide to form a second peripheral area located on the outer periphery of the waveguide;

A first metal electrode is provided in the second peripheral area on the substrate and is located at the periphery of the second side end of the waveguide. The first metal electrode is separated from the waveguide by a preset distance. a metal electrode in contact with the first peripheral region of the van der Waals heterojunction; and,

A second metal electrode is provided on a side of the van der Waals heterojunction facing away from the waveguide.

Optionally, the width d1 of the second metal electrode is smaller than the width d2 of the first metal electrode.

Optionally, the preset distance between the first metal electrode and the waveguide is 0.2-5 μm.

Optionally, the thickness of the waveguide is 200-500nm, and the width is 500-1500nm.

Optionally, the thickness of the first metal electrode and the second metal electrode is both 40-100 nm; and/or the thickness of the substrate is 0.4-0.7 mm.

The invention also provides a method for preparing a waveguide integrated photodetector. The p-type two-dimensional semiconductor layer and the n-type two-dimensional semiconductor layer in the van der Waals heterojunction are prepared by mechanical stripping.

In the technical solution of the present invention, the waveguide-integrated photodetector includes a waveguide and a van der Waals heterojunction; the van der Waals heterojunction includes a p-type two-dimensional semiconductor layer provided on one side of the waveguide, and a p-type two-dimensional semiconductor layer provided on one side of the waveguide. The two-dimensional semiconductor layer faces away from the n-type two-dimensional semiconductor layer on one side of the waveguide. As a result, the flow of electrons and holes will form a sudden change in potential at the van der Waals heterojunction interface to generate a built-in electric field. This built-in electric field can serve as a potential barrier for free carrier movement in the device without light, reducing dark current. ; At the same time, it can also speed up the separation of photogenerated carriers, improve the carrier extraction rate, and thereby improve the photoresponsivity and photoresponse rate.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without exerting creative efforts.

Figure 1 is a schematic cross-sectional structural diagram of a waveguide integrated photodetector provided by an embodiment of the present invention;

Figure 2 is a schematic three-dimensional structural diagram of a waveguide integrated photodetector provided by an embodiment of the present invention;

Figure 3 is a waveguide-integrated photodetector provided by an embodiment of the present invention using a BP/MoTe ₂ van der Waals heterojunction, and the energy band diagram of the BP/MoTe ₂ at thermal equilibrium of the waveguide-integrated photodetector;

Figure 4 is a mode field distribution diagram of the direct contact portion between the BP/MoTe ₂ van der Waals heterojunction and the rectangular silicon waveguide in the waveguide integrated photodetector provided by an embodiment of the present invention.

Explanation of reference numbers:

label name label name 100 Waveguide integrated photodetector twenty two n-type two-dimensional semiconductor layer 1 waveguide twenty three first peripheral area 11 first side end 3 substrate 12 second side end 31 Second peripheral area 2 van der Waals heterojunction 4 first metal electrode twenty one p-type two-dimensional semiconductor layer 5 second metal electrode

The realization of the purpose, functional features and advantages of the present invention will be further described with reference to the embodiments and the accompanying drawings.

Detailed ways

In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the examples, the conditions should be carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not indicated, they are all conventional products that can be purchased commercially. In addition, the meaning of "and/or" appearing in the entire text includes three parallel solutions. Taking "A and/or B" as an example, it includes solution A, or solution B, or a solution that satisfies both A and B at the same time. In addition, the technical solutions in the various embodiments can be combined with each other, but it must be based on what a person of ordinary skill in the art can implement. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that such a combination of technical solutions does not exist. , nor within the protection scope required by the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

In order to meet the development needs of silicon-based optoelectronic integrated chips, waveguide integrated photodetectors have gradually become the focus of research on silicon-based photodetectors and have better industrialization value. In typical research on waveguide-integrated 2D material photodetectors, the bandwidth of graphene-based photodetectors can reach 150GHz, but the zero-bandgap characteristics of graphene will cause larger dark currents and larger metal components in the device. The contact area will cause large losses. There are also field-effect transistors based on p-n homogeneous structures of 2D materials. Although the devices have a bandwidth response of >10GHz under zero bias, they still have shortcomings in suppressing thermal noise (reducing dark current) and improving photoresponsivity.

In view of this, referring to Figures 1-2, the present invention proposes a waveguide integrated photodetector 100, which includes a waveguide 1 and a van der Waals heterojunction 2; the van der Waals heterojunction 2 includes a p disposed on one side of the waveguide 1 type two-dimensional semiconductor layer 21, and an n-type two-dimensional semiconductor layer 22 provided on the side of the p-type two-dimensional semiconductor layer 21 facing away from the waveguide 1.

In the technical solution of the present invention, the flow of electrons and holes will form a sudden change in potential at the interface of the van der Waals heterojunction 2 to generate a built-in electric field. The built-in electric field can serve as a potential barrier for free carrier movement in the device without light. , the potential barrier formed at the heterojunction interface will inhibit the transmission of random carriers, thereby reducing the dark current and noise level in the device; at the same time, the built-in electric field generated by the potential barrier at the heterojunction interface can effectively separate the photogenerated carriers. The separation of carriers leads to faster optical response, expands the effective bandwidth, and improves photoresponsivity and photoresponse rate.

In some embodiments of the present invention, the material of the p-type two-dimensional semiconductor layer 21 includes black phosphorus. The material of the n-type two-dimensional semiconductor layer 22 includes one of MoTe ₂ , MoSe ₂ , and WSe ₂ .

The characteristics of heterojunctions are mainly determined by the energy band matching of the interface. According to the energy band matching characteristics of the interface, heterojunctions can be divided into type I spanning energy gap, type II staggered energy gap and type III non-overlapping type. Among them, both type I and type II can expand the effective band gap, and will form a built-in electric field at the interface due to a sudden change in potential. Black phosphorus is a direct band gap 2D material with narrow band gap and high carrier mobility. It has in-plane anisotropy. This material is used as the photosensitive layer of the detector. It has strong light absorption and can be directly combined with silicon. Waveguide heterogeneous integration. In the embodiment of the present invention, the n-type two-dimensional semiconductor layer 22 such as MoTe ₂ , MoSe ₂ , WSe ₂ and black phosphorus are directly tightly combined through van der Waals forces to form a type I van der Waals heterojunction, and the energy band bending of the contact interface will form a built-in electric field. The built-in electric field has the effect of effectively suppressing the movement of free carriers (reducing dark current) and accelerating the interface separation of photogenerated carriers.

See Figure 3. Figure 3 is an energy band diagram of the few-layer 2D semiconductor black phosphorus/MoTe ₂ van der Waals heterojunction. The band gaps of black phosphorus and MoTe ₂ are ~0.3eV and ~0.9eV respectively. The van der Waals heterostructure is composed of Type I effective energy band gap covering the communication band. In the thermal equilibrium state, the Fermi level EF is close to the valence band (EV) of the p-type semiconductor black phosphorus and the conduction band (EC) of the n-type semiconductor MoTe2, forming a typical PN junction. Due to the flow of electrons (marked by the black circle "-" in Figure 3) and holes (marked by the black circle "+" in Figure 3), a sudden change in potential is formed at the heterojunction interface, resulting in a built-in electric field (shaded area in Figure 3) , the built-in electric field can serve as a potential barrier for free carrier movement in the device without light, reducing dark current; it can also speed up the separation of photogenerated carriers, improve the carrier extraction rate, and thereby improve the photoresponsivity.

In some embodiments of the present invention, the thickness of the p-type two-dimensional semiconductor layer 21 is 1-200 nm; the thickness of the n-type two-dimensional semiconductor layer 22 is 1-200 nm. The p-type two-dimensional semiconductor layer 21 or the n-type two-dimensional semiconductor layer 22 with this thickness may be a single layer or a few layers. Here, few-layer refers to the thin thickness of the two-dimensional semiconductor material (for example, less than 200nm). The reason for the formation of the thinner few-layer semiconductor is that the semiconductor layers are bonded together by the weak van der Waals force. At the same time, external force can be easily used to break the interlayer constraints, thereby forming a thinner few-layer semiconductor.

In a feasible manner, the material of the waveguide 1 includes one of silicon, silicon nitride, and lithium niobate; the waveguide 1 includes a rectangular waveguide, a ridge waveguide, or a groove waveguide.

In some embodiments of the present invention, the waveguide 1 has a first side end 11 and a second side end 12 connected to the first side end 11 , wherein one of the first side end 11 is used to receive incident light. Light; the van der Waals heterojunction 2 is arranged beyond the waveguide 1 on the peripheral side of the waveguide 1 to form a first peripheral area 23 located on the outer periphery of the waveguide 1; the waveguide 1 integrated photodetector also It includes: substrate 3, first metal electrode 4 and second metal electrode 5. Wherein, the substrate 3 is disposed on the other side of the waveguide 1 , and the substrate 3 is disposed beyond the waveguide 1 on the peripheral side of the waveguide 1 to form a third layer located on the outer periphery of the waveguide 1 . Two peripheral areas 31; the first metal electrode 4 is provided in the second peripheral area 31 on the substrate 3 and is located at the periphery of the second side end 12 of the waveguide 1. The first metal electrode 4 Separated from the waveguide 1 by a preset distance, the first metal electrode 4 is in contact with the first peripheral region 23 of the van der Waals heterojunction 2; the second metal electrode 5 is disposed on the back of the van der Waals heterojunction 2. to one side of the waveguide 1.

In the waveguide 1 integrated photodetector provided by the present invention, on the one hand, black phosphorus is used as the light-absorbing layer material. When no light passes through the waveguide 1, the built-in electric field on the two surfaces of the van der Waals heterojunction can serve as a potential for free carrier movement. barrier, so there will be less dark current in the device than a photodetector based on a single 2D material. When light (for example, light with a wavelength range of 850nm-2000nm) passes through the waveguide 1, the evanescent wave of the light field mode in the waveguide 1 has a spatial overlap with the black phosphorus, as shown in Figure 4. Black phosphorus absorbs the energy of photons and excites electrons in its valence band to the conduction band to form electron-hole pairs. At this time, under the quantum confinement effect caused by the unique out-of-plane nanoscale size of 2D materials, these photogenerated electrons - The hole pairs are bound together through strong Coulomb interactions and have localized properties (exciton properties). This feature will extend the carrier lifetime, allowing enough time to extract the photogenerated carriers before recombination to form a photocurrent, thus having a high optical gain. This process completes the conversion of optical signals into electrical signals. On the other hand, the carrier collection direction in the waveguide 1 integrated photodetector is perpendicular to the direction of the waveguide 1, and the incident direction of light is perpendicular to the carrier transport direction, so that the interaction between responsivity and bandwidth can be basically eliminated. Constraint, while increasing the bandwidth, it can also ensure a relatively high device responsivity. Compared with the existing strategy of collecting carriers parallel to the waveguide 1 direction, it can effectively compensate for the longer transmission time of carriers in 2D materials, resulting in smaller transit time and faster response speed. .

It should be noted that in the embodiment of the present invention, the second metal electrode 5 is disposed on the side of the van der Waals heterojunction 2 facing away from the waveguide 1 , and the first metal electrode 4 is disposed on the substrate 3 The second peripheral region 31 is located at the periphery of the second side end 12 of the waveguide 1 and is in contact with the first peripheral region 23 of the van der Waals heterojunction 2 . The first metal electrode 4 and the waveguide 1 are separated by a predetermined distance. Set distance. The first metal electrode 4 serves as a drain, the second metal electrode 5 serves as a source, and the substrate 3 serves as a gate. The electrode structure thus arranged can apply an electric field perpendicular to the direction of light incidence in the waveguide 1. By applying a bias voltage perpendicular to the direction of the waveguide 1 and collecting photogenerated carriers along this direction, the transit time of the carriers can be reduced. At the same time, in the present invention, asymmetric metal electrodes are made in the direction perpendicular to the waveguide 1, which can effectively reduce the contact resistance between the metal and the 2D semiconductor, making the effective area of the electrode very small, thereby reducing the resistance of the entire loop. capacitance.

In the embodiment of the present invention, the substrate 3 may be a heavily doped substrate 3, such as a silicon substrate heavily doped with boron, represented by Si(p++). The first metal electrode 4 and the second metal electrode 5 may be made of conductive metals such as gold, titanium, and chromium. The first metal electrode 4 and the second metal electrode 5 may be made of the same metal material or different metal materials. The first metal electrode 4 and the second metal electrode 5 may be a single metal material such as gold, or a composite metal material such as an alloy of chromium and gold.

In some embodiments of the present invention, the width d1 of the second metal electrode 5 is smaller than the width d2 of the first metal electrode 4 . In this way, the second metal electrode 5 on the top has a narrow contact point. This design can effectively reduce the capacitance and resistance of the entire loop, thereby improving the operating bandwidth of the device.

In some embodiments of the present invention, the preset distance between the first metal electrode 4 and the waveguide 1 is 0.2-5 μm. The preset distance is controlled within an appropriate range. When a voltage is applied to the second metal electrode 5, the external electric field generated by the device can have a vertical component electric field that passes through the van der Waals heterojunction in the vertical direction. The vertical direction refers to the direction from the second metal electrode 5 to the waveguide 1 .

In some embodiments of the present invention, the thickness of the waveguide 1 is 200-500 nm, and the width is 500-1500 nm.

In some embodiments of the present invention, the thickness of the first metal electrode 4 and the second metal electrode 5 is both 40 to 100 nm; the thickness of the substrate 3 is 0.4 to 0.7 mm.

Embodiments of the present invention also provide a method for preparing a waveguide 1 integrated photodetector. The p-type two-dimensional semiconductor layer 21 and the n-type two-dimensional semiconductor layer 22 in the van der Waals heterojunction 2 are prepared by a mechanical peeling method.

The preparation method proposed by the present invention has simple steps and high preparation efficiency; in addition, the preparation method of the waveguide 1 integrated photodetector proposed by the present invention, the prepared waveguide 1 integrated photodetector has the above-mentioned waveguide 1 integrated photodetector All the beneficial effects of the device will not be repeated here.

The technical solution of the present invention will be further described in detail below with reference to specific embodiments and drawings. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the present invention.

Example 1

Referring to Figure 1, this embodiment provides a waveguide-integrated photodetector, which from bottom to top is: substrate, waveguide, few-layer black phosphorus layer, few-layer MoTe ₂ , and second metal electrode, wherein the few-layer The black phosphorus layer and few-layer MoTe ₂ form a van der Waals heterojunction. The waveguide has a first side end and a second side end connected to the first side end. One of the first side ends is used to receive incident light; the van der Waals heterojunction The mass junction is disposed beyond the waveguide on the circumferential side of the waveguide to form a first peripheral region located on the outer circumference of the waveguide. The substrate is disposed beyond the waveguide on the peripheral side of the waveguide to form a second peripheral area located on the outer periphery of the waveguide; the first metal electrode is disposed in the second peripheral area on the substrate and is located on the periphery of the second side end of the waveguide, The first metal electrode is separated from the waveguide by a preset distance, and the first metal electrode is in contact with the first peripheral region of the van der Waals heterojunction.

In this embodiment, the thickness of the few-layer black phosphorus layer is 100 nm, and the thickness of the few-layer MoTe ₂ is 100 nm. The material of the waveguide is silicon, the waveguide is a rectangular waveguide, the thickness of the waveguide is 200nm, and the width is 500nm. The first metal electrode and the second metal electrode are both made of gold, and the thickness of the first metal electrode and the second metal electrode is 80nm; the width of the second metal electrode is 500nm, and the thickness of the first metal electrode is 500nm. The width is 1 μm, and the preset distance between the first metal electrode and the waveguide is 0.2 μm. The substrate material is a standard SOI (Silicon On Insulator) wafer, which is a heavily doped silicon substrate from bottom to top with a thickness of 0.4 mm. It mainly supports the entire device and serves as the gate of the device. effect. The buried oxide layer on the doped silicon substrate is silicon dioxide with a thickness of 2 μm, which mainly plays the role of supporting the entire device.

Example 2-18

The waveguide integrated photodetector provided in Embodiment 2-18 is basically the same as that in Embodiment 1, except that the materials or sizes are different. Please refer to Table 1 for details of these differences.

Table 1

Table 2

Example 19

This embodiment provides a method for preparing a waveguide integrated photodetector, which method includes:

The substrate in this embodiment uses a standard SOI (Silicon On Insulator) wafer, which is a heavily doped silicon substrate from bottom to top with a thickness of 0.4 mm. It mainly supports the entire device and serves as the gate of the device. ) function. The buried oxide layer on the doped silicon substrate is silicon dioxide with a thickness of 2 μm, which mainly plays the role of supporting the entire device.

Using Electron Beam Lithography (EBL) and Inductively Coupled Plasma etching (ICP) technology, a rectangular silicon waveguide with a thickness of 200nm and a width of 500nm was obtained.

The first metal electrode is deposited by standard photolithography processes and electron beam evaporation techniques.

The few-layer 2D semiconductor black phosphorus and the few-layer 2D semiconductor MoTe2 obtained by the mechanical stripping method are sequentially transferred to the waveguide, and the waveguide is covered, and the few-layer 2D semiconductor black phosphorus and the few-layer 2D semiconductor MoTe2 cover part of the first metal electrode .

The second metal electrode is deposited through standard photolithography process and electron beam evaporation technology to obtain a waveguide integrated photodetector.

The waveguide integrated photodetectors provided in the above embodiments all include waveguides and van der Waals heterojunctions. As a result, the flow of electrons and holes will form a sudden change in potential at the van der Waals heterojunction interface to generate a built-in electric field. This built-in electric field can serve as a potential barrier for free carrier movement in the device without light, reducing dark current. ; At the same time, it can also speed up the separation of photogenerated carriers, improve the carrier extraction rate, and thereby improve the photoresponsivity.

The above are only preferred embodiments of the present invention, which do not limit the patent scope of the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the patent protection scope of the present invention.

Claims (10)

1. A waveguide integrated photodetector, comprising a waveguide and a van der waals heterojunction; the van der Waals heterojunction comprises a p-type two-dimensional semiconductor layer arranged on one side of the waveguide, and an n-type two-dimensional semiconductor layer arranged on the side of the p-type two-dimensional semiconductor layer opposite to the waveguide.

2. The waveguide integrated photodetector of claim 1, wherein the material of said p-type two-dimensional semiconductor layer comprises black phosphorus; and/or the material of the n-type two-dimensional semiconductor layer comprises MoTe ₂ 、MoSe ₂ 、WSe ₂ One of them.

3. The waveguide integrated photodetector according to claim 1 or 2, wherein the thickness of the p-type two-dimensional semiconductor layer is 1 to 200nm; and/or the number of the groups of groups,

the thickness of the n-type two-dimensional semiconductor layer is 1-200 nm.

4. The waveguide integrated photodetector of claim 1, wherein the material of the waveguide comprises one of silicon, silicon nitride, lithium niobate; and/or the number of the groups of groups,

the waveguide includes a rectangular waveguide, a ridge waveguide, or a slot waveguide.

5. The waveguide integrated photodetector of claim 1, wherein said waveguide has a first side end and a second side end connected to the first side end, wherein one of said first side ends is configured to receive incident light;

the van der waals heterojunction is arranged beyond the waveguide on the peripheral side of the waveguide to form a first peripheral region located at the periphery of the waveguide;

the waveguide integrated photodetector further includes:

a substrate disposed on the other side of the waveguide, and disposed beyond the waveguide on a peripheral side of the waveguide to form a second peripheral region located at the periphery of the waveguide;

the first metal electrode is arranged in a second peripheral area on the substrate and is positioned at the periphery of the second side end part of the waveguide, a preset distance is reserved between the first metal electrode and the waveguide, and the first metal electrode is in contact with the first peripheral area of the van der Waals heterojunction; the method comprises the steps of,

and the second metal electrode is arranged on one side of the van der Waals heterojunction opposite to the waveguide.

6. The waveguide-integrated photodetector of claim 5, wherein the width d1 of said second metal electrode is less than the width d2 of said first metal electrode.

7. The waveguide-integrated photodetector of claim 5, wherein the predetermined distance between the first metal electrode and the waveguide is 0.2-5 μm.

8. The waveguide integrated photodetector of claim 6, wherein said waveguide has a thickness of 200-500 nm and a width of 500-1500 nm.

9. The waveguide integrated photodetector of claim 6, wherein said first metal electrode and said second metal electrode each have a thickness of 40-100 nm; and/or the number of the groups of groups,

the thickness of the substrate is 0.4-0.7 mm.

10. A method for manufacturing a waveguide integrated photodetector according to any one of claims 1 to 9, wherein the p-type two-dimensional semiconductor layer and the n-type two-dimensional semiconductor layer in the van der waals heterojunction are manufactured by a mechanical lift-off method.