CN213988899U

CN213988899U - Terahertz detection component based on InSe material

Info

Publication number: CN213988899U
Application number: CN202022732369.5U
Authority: CN
Inventors: 宋雪梅; 郭萌萌; 张永哲
Original assignee: Beijing University of Technology
Current assignee: Beijing University of Technology
Priority date: 2020-11-23
Filing date: 2020-11-23
Publication date: 2021-08-17
Anticipated expiration: 2030-11-23

Abstract

A terahertz detection component based on an InSe material belongs to the terahertz field. The substrate layer is horizontally arranged on the lowest layer, the insulating medium layer is horizontally arranged on the upper surface of the substrate, the protective layer a is horizontally arranged on the upper surface of the insulating medium layer, the InSe layer is arranged above the protective layer a in parallel, the protective layer b is horizontally arranged above the InSe layer, and the protective layer b completely covers the InSe layer; the source electrode and the drain electrode are arranged on two sides of the InSe material, cover the edge of the exposed InSe and are positioned above the insulating layer of the top gate electrode without contacting with the internal InSe; the antenna is positioned on the side of the source electrode and the grid electrode, which are far away from the InSe material, and is respectively connected with the source electrode and the grid electrode. The terahertz wave detector has stronger absorption capacity and conversion capacity to incident terahertz waves, lower contact resistance and cleaner working environment, realizes wide-spectrum detection to terahertz waves of different wave bands, and realizes switching of the device by changing gate voltage.

Description

Terahertz detection component based on InSe material

The technical field is as follows:

the utility model relates to a terahertz technical field, especially a terahertz detection device based on two-dimensional material.

Background art:

terahertz waves refer to electromagnetic waves with a frequency of 0.1-10THz and have a wavelength range of 0.03-3 mm. The terahertz waves are located in the electromagnetic spectrum between microwaves and infrared radiation. To date, most of the bands of the electromagnetic spectrum other than the terahertz band have been widely studied and used, and the terahertz wave has not been sufficiently studied and used due to the lack of an effective radiation generation and detection method. In recent years, with the development of laser technology and semiconductor technology, a stable and reliable excitation light source is provided for the generation of terahertz pulses, and terahertz waves are widely applied to various fields due to various characteristics of safety, high penetrability, fingerprint spectrum, bandwidth and the like. The wide application of terahertz waves is not independent of the development of detectors. The existing terahertz direct detection technology can be divided into a photo-thermal detector and a photoelectron detector according to the detection principle. Although the photothermal detector has a wide response range, due to the influence of heat capacity and the like, the response speed is in the millisecond order, and the application of the photothermal detector is restricted to a certain extent. The other type of detector based on the principle, namely a photoelectron detector, theoretically has response to terahertz signals reaching ns magnitude, but most of the detectors need a low-temperature environment. At present, a terahertz wide-spectrum detector with high sensitivity, high responsivity and low noise equivalent power working at room temperature is urgently to be developed.

The discovery of graphene opens up the research heat of two-dimensional materials, and the two-dimensional materials are connected by stronger covalent bonds in the layers and are connected by weaker van der waals force, namely, the two-dimensional layered materials with single layer or few layers can be obtained by a mechanical stripping method. Indium selenide (InSe) is a complex group III-V semiconductor material, wherein InSe is a typical layered structure formed by stacking four atoms of Se-In-Se and has small effective electron mass (0.143 m)₀) Exhibit high electron mobility (10)³cm²·V^-1·s^-1) And is in pairThe surrounding environment is relatively stable. The field effect transistor constructed based on plasma wave resonance has great potential for terahertz detection. In practice, the performance of electronic devices can be affected by various scattering that can degrade the performance of the device, especially between the dielectric layer and the channel material.

Aiming at the requirements for the performance of the terahertz detector, a field effect detector based on a plasma wave detection principle is provided. The utility model discloses a two-dimensional material InSe that has high carrier mobility is the material that bears of two-dimensional electron gas, by the protection material encapsulation, with the accurate one-dimensional contact of metal electrode to planar antenna is supplementary absorption terahertz wave, and the preparation has low contact resistance, and super wide spectrum absorbs the terahertz unit device of response.

The utility model has the following contents:

to the problem that exists at present, the utility model aims at: the multilayer InSe is used as a bearing material of two-dimensional electron gas to prepare a terahertz unit device with low contact resistance and ultra-wide spectrum absorption response.

In order to realize the above purpose, the utility model discloses a technical scheme be: the utility model relates to a terahertz detection device component based on InSe material, which comprises a substrate layer (1), an insulating medium layer (2), a protective layer a layer (3a), a protective layer b layer (3b), an InSe layer (4), a source electrode (5a), a drain electrode (5b), a top gate electrode (6) and an antenna (7); the substrate layer is horizontally arranged at the lowest layer, the insulating medium layer is horizontally arranged on the upper surface of the substrate, the protective layer a is horizontally arranged on the upper surface of the insulating medium layer, the InSe layer (4) is arranged above the protective layer a (3a) in parallel, the protective layer b (3b) is horizontally arranged above the InSe layer, and the protective layer b completely covers the InSe layer; the source electrode (5a) and the drain electrode (5b) are arranged on two opposite sides of the InSe material, the source electrode and the drain electrode respectively cover the edge of the exposed InSe, and the top gate electrode (6) is positioned above the protective layer b layer (3b) and is not in contact with the internal InSe; and the antennas (7) are respectively connected with the source electrode and the side edge of the grid electrode, which is far away from the InSe material side.

The substrate layer is square, the side length is 1-5cm, the thickness is 100-500 mu m, the resistivity is more than 10000 omega cm, the material is one of a monocrystalline high-resistance silicon wafer, a diamond film and TPX (poly-4-methylpentene), and the monocrystalline high-resistance silicon wafer is preferably selected.

The insulating medium layer is square, has the same size with the substrate layer side, the side length is 1-5cm, the thickness is 0.2-1 μm, and the dielectric constant is 1-10; the material is one of silicon dioxide, silicon nitride, aluminum oxide and hafnium oxide, and preferably silicon dioxide.

The protective layer a and the protective layer b are used for packaging the InSe material to keep the working environment clean, and the protective layer b is used as a gate medium and used for regulating and controlling the concentration of electron gas of the InSe layer through an electric field.

The InSe layer is made of multiple layers of InSe materials, the thickness of the InSe layer is 4-10nm, the InSe layer is in a strip pattern, two-dimensional electron gas can be provided, and plasma waves are generated and used for terahertz wave detection.

The source electrode, the drain electrode and the top gate electrode (6) are one or a combination of more of gold, titanium, nickel and chromium, and an upper-layer structure and a lower-layer structure are adopted during compounding; the length of the source electrode, the drain electrode and the top gate electrode (6) is 8mm-40mm, the width is 0.5mm-5mm, the thickness is 10-100nm, and the conductivity is 2 multiplied by 10⁵-6×10⁷S/m。

The antenna is of a butterfly antenna structure, namely two sectors are opposite, corresponding edges at the central angle are opposite, and the corresponding edges at the central angle of each sector are respectively connected with a source electrode (5a) and a drain electrode (5 b). The material is one or a plurality of gold, titanium, nickel and chromium, and an upper layer structure and a lower layer structure are adopted during compounding.

To sum up, owing to adopted above-mentioned technical scheme, the beneficial effects of the utility model are that: the utility model discloses a terahertz detector that InSe is base under electric field regulation compares in the terahertz detector of other materials, and InSe has super high carrier mobility, can realize the room temperature detection to terahertz wave high sensitivity, high responsivity, low noise through electric field regulation and control.

Description of the drawings:

fig. 1 is a top view of terahertz detection components and parts structure based on InSe material.

Fig. 2 is a cross-sectional view of channel arrow department in a terahertz detection components and parts structure chart 1 based on InSe material.

Fig. 3 is an I-V diagram of the electrical test according to the present invention.

The labels in the figure are: 1-comprises a substrate layer, 2-an insulating dielectric layer, 3 a-a protective layer, 3 b-b protective layer, 4-InSe layer, 5 a-source electrode, 5 b-drain electrode, 6-top gate electrode and 7-antenna.

The specific implementation mode is as follows:

the technical solution of the present invention is further described below with reference to the embodiments, but not limited thereto, and all modifications or equivalent replacements of the technical solution of the present invention may be made without departing from the spirit and scope of the technical solution of the present invention.

Example 1

An InSe-based terahertz detector element is shown in fig. 1, 2 and 3 and comprises a substrate layer, an insulating dielectric layer, an InSe material layer, a protective layer a layer, a protective layer b layer, a source electrode, a drain electrode, a top gate electrode and an antenna. The substrate layer 1 is horizontally arranged on the lowermost layer, the insulating medium layer is horizontally arranged on the upper surface of the substrate, the InSe material layer is arranged in the middle of the upper surface of the insulating medium layer in parallel, the protective layer a layer and the protective layer b layer are arranged on the upper surface and the bottom of the InSe material layer, the InSe material layer is packaged inside the protective layer, the source electrode and the drain electrode are arranged on two sides of the InSe material layer and cover the edge of the InSe material layer, and the top gate electrode 6 is arranged above the protective layer b and is not in contact with the InSe material layer.

The substrate layer adopted in the embodiment is a square monocrystalline high-resistance silicon wafer, the side length is 1cm, the thickness is 100 mu m, and the resistivity is more than 10000 omega cm. The insulating medium layer is made of square silicon dioxide, the side length is 1cm, and the thickness is 0.3 mu m. The protective layer is mechanically stripped hexagonal boron nitride (hBN), the number of layers is 10-20, the InSe material layer is a plurality of layers of InSe obtained by mechanical stripping, and the InSe material layer is transferred into the hBN in a fixed point mode. In the transfer process, in order to ensure the cleanliness of the InSe material, the intrinsic ultrahigh carrier mobility is reduced. We chose a thermal dry transfer material. First two dimensionsExfoliation and dry transfer of materials hBN and InSe: firstly, adhering part of hBN blocks on an adhesive tape, folding for multiple times to enable the hBN blocks to be uniformly distributed, then using PDMS (polydimethylsiloxane) to be in bubble-free contact with the adhesive tape, heating the PDMS at 120 ℃ for 1min to transfer a little of multilayer hBN to the PDMS, observing the PDMS under an optical microscope, selecting about 10-20 layers of hBN, and transferring the hBN to a clean silicon wafer A to obtain a protective layer a; adhering part of InSe blocks on an adhesive tape, folding for multiple times to enable the InSe blocks to be uniformly distributed, then using a clean silicon wafer B to be in bubble-free contact with the adhesive tape, transferring a little multilayer InSe, observing under an optical microscope, and selecting the multilayer InSe with about 5-8 layers; repeating the mechanical stripping step to strip the protective layer B, but not transferring to a silicon wafer, transferring to selected InSe by using a selected hBN fixed point on PDMS, spin-coating PPC (polypropylene carbonate) on PDMS, picking up hBN + InSe on the silicon wafer B by using PPC + PDMS, aligning hBN on the silicon wafer A under an optical microscope, heating to 100 ℃ to release hBN + InSe, and finally forming an hBN + InSe + hBN laminated layer on the silicon wafer B. At the moment, the InSe is completely wrapped by hBN, an EBL (electron beam exposure system) is adopted to pattern a grid region, a contact point of a source electrode and a drain electrode is etched by RIE (reactive ion etching), and at the moment, the edge of the multilayer InSe is in a one-dimensional contact state with a metal electrode, so that the contact resistance is greatly reduced. Finally, the antenna was prepared by photolithography and electron beam evaporation, and the EBL connected the antenna (radius 330 μm (300GHz)) to the electrode. The prepared device element is subjected to electrical test to obtain an I-V curve of the device element, the contact resistance is reduced by one order of magnitude compared with surface contact, and the performance of the device is greatly improved. The utility model discloses a two-dimensional material InSe is the channel material, and the InSe material has 10³ cm²·V^-1·s^-1Can be compared with black phosphorus, and can be stably existed in air. The channel material InSe is packaged by adopting an insulating material hBN without dangling bonds on the surface, so that scattering between the channel material InSe and a substrate is reduced, and pollution of a deposited gate medium to the InSe material is avoided. The contact resistance of the channel material InSe and the metal electrode is greatly reduced by adopting quasi-one-dimensional contact, the structure of the device is further optimized, and the performance of the device is improved.

Claims

1. A terahertz detection component based on an InSe material is characterized by comprising a substrate layer (1), an insulating dielectric layer (2), a protective layer a layer (3a) and a protective layer b layer (3b), an InSe layer (4), a source electrode (5a), a drain electrode (5b), a top gate electrode (6) and an antenna (7); the substrate layer is horizontally arranged at the lowest layer, the insulating medium layer is horizontally arranged on the upper surface of the substrate, the protective layer a is horizontally arranged on the upper surface of the insulating medium layer, the InSe layer (4) is arranged above the protective layer a (3a) in parallel, the protective layer b (3b) is horizontally arranged above the InSe layer, and the protective layer b completely covers the InSe layer; the source electrode (5a) and the drain electrode (5b) are arranged on two opposite sides of the InSe material, the source electrode and the drain electrode respectively cover the edge of the exposed InSe, and the top gate electrode (6) is positioned above the protective layer b layer (3b) and is not in contact with the internal InSe; and the antennas (7) are respectively connected with the source electrode and the side edge of the grid electrode, which is far away from the InSe material side.

2. The terahertz detection component based on the InSe material as claimed in claim 1, wherein the substrate layer is square, the side length is 1-5cm, the thickness is 100-500 μm, the resistivity is greater than 10000 Ω -cm, and the material is one of a single crystal high-resistance silicon wafer, a diamond film and TPX.

3. The terahertz detection component based on the InSe material as claimed in claim 1, wherein the insulating medium layer is square, has the same size with the substrate layer side, the side length is 1-5cm, the thickness is 0.2-1 μm, and the dielectric constant is 1-10; the material is one of silicon dioxide, silicon nitride, aluminum oxide and hafnium oxide.

4. The terahertz detection component based on the InSe material as claimed in claim 1, wherein the protective layer a and the layer b are used for packaging the InSe material and keeping the working environment clean, and the layer b is used as a gate dielectric for regulating and controlling the concentration of electron gas in the InSe layer by an electric field; the InSe layer is made of multiple layers of InSe materials, the thickness of the InSe layer is 4-10nm, the InSe layer is in a strip pattern, two-dimensional electron gas can be provided, and plasma waves are generated and used for terahertz wave detection.

5. The terahertz detection component based on the InSe material as claimed in claim 1, wherein the source electrode, the drain electrode and the top gate electrode (6) are one or a combination of gold, titanium, nickel and chromium, and an upper-layer structure and a lower-layer structure are adopted during combination; the length of the source electrode, the drain electrode and the top gate electrode (6) is 8mm-40mm, the width is 0.5mm-5mm, the thickness is 10-100nm, and the conductivity is 2 multiplied by 10⁵-6×10⁷S/m。

6. A thz detection component based on InSe material as claimed in claim 1, wherein the antenna is a butterfly antenna structure, that is, two sectors are opposite, the corresponding sides at the central corners are opposite, and the corresponding sides at the central corners of each sector are respectively connected to the source electrode (5a) and the drain electrode (5 b).