18 results about "Surface states" patented technology

A system comprising a quantum information engine (QIE). The QIE includes a topological surface state three-dimensional topological insulator (TSS-3DTI) to flow, in a first flow direction from an input side to an output side, electrons having a first spin-momentum. The TSS-3DTI includes a first surface. The first surface has first spin-momentum locked charge carriers and a plurality of first magnetic impurities having a second average nuclear spin polarization. The TSS-3DTI stores information in the first surface at the points of interaction that occur between the plurality of first magnetic impurities interacting with the flowing electrons to exchange, at each point of interaction, a nuclear spin of a respective first magnetic impurity with an electron spin of a respective flowing electron. The system can include at least one surface. The system can harvest energy from other integrated circuits. A method of storing quantum energy is also provided.

The application discloses a ternary transition metal chalcogenide and application thereof in a terahertz detector, and realizes high-speed, high-sensitivity and room-temperature wide-spectrum terahertz detection under the driving of a strong topological surface state of the ternary transition metal chalcogenide.

The invention discloses a topological insulator solid solution wave-absorbing material and a preparation method thereof, and belongs to the field of electromagnetic wave absorbing materials. The invention aims to solve the problem that an existing topological insulator wave-absorbing material is difficult to deal with a complex electromagnetic environment. The chemical expression of the invention is Mn < 1-x > Sn < x > Bi < 2 > Te < 4 >. The topological insulator single crystal grows through spontaneous nucleation. According to the invention, the Sn element is introduced for doping, the energy level position of the topological surface state is adjusted, and the intrinsic high impedance matching advantage of the topological insulator is combined, so that the excellent electromagnetic wave absorption performance is obtained.

The invention provides an epitaxial layer structure of a doped InSb film and a preparation process thereof, based on an MOCVD (Metal Organic Chemical Vapor Deposition) process, an InSb: Te layer and an InSb layer are periodically and alternately grown to form a doped InSb functional layer of a Hall element, the band gap of an InSb material can be increased, and the temperature coefficient of the Hall element of the InSb film is reduced; furthermore, according to the epitaxial layer structure and the preparation process provided by the invention, uniform doping can be realized, excessive Te doping can be avoided, and the defect density and the surface state density of the doped InSb functional layer can be reduced, so that the sensitivity of the InSb Hall element is improved, and the background noise of the Hall element is reduced. Besides, according to the epitaxial layer structure of the doped InSb film and the preparation process thereof provided by the invention, the growth processes, materials, thicknesses and the like of the buffer layer and the gradient layer are further improved, lattice mismatch between the substrate and the InSb film is slowed down, the dislocation density of the InSb film caused by mismatch is reduced, the InSb film with higher mobility can be grown, and the yield of the InSb film is improved. And therefore, higher sensitivity can be obtained on the Hall element.

The application discloses a material structure for improving GaN heterojunction electron mobility and an epitaxial growth method thereof. The structure comprises, from bottom to top, a single crystal substrate, an AlN nucleation layer, a GaN buffer layer, an AlN insertion layer, a GaN isolation layer, a lower AlGaN barrier layer, an upper AlGaN barrier layer and an InGaN cap layer. The epitaxial growth method is characterized in that: the GaN isolation layer is introduced to suppress alloy disorder scattering; the lower barrier layer is grown by using a high V / III ratio low-speed process to reduce defects, and the upper barrier layer is grown by using a low V / III ratio high-speed process to improve the interface morphology; and finally, the InGaN cap layer is grown to relieve stress and reduce surface states. The application can synergistically suppress multiple scattering mechanisms, and the room temperature electron mobility is improved to 2270 cm 2 / V·s or above, and the surface roughness is significantly reduced, thereby providing a key material basis for high-performance GaN microwave devices.

The recording device selects cleaning control in response to the occurrence of an event. Therefore, it does not necessarily perform cleaning of the conveyor belt in accordance with the degree of contamination of the conveyor belt. [Solution] A recording device for recording on a recording medium, comprising: a recording means for performing the recording by ejecting ink onto the recording medium; a medium transport belt for transporting the recording medium on which the recording is performed by the recording means; a cleaning means that is movable to a contact position in contact with the medium transport belt or to a non-contact position not in contact with the medium transport belt, and performs a cleaning operation on the medium transport belt when located at the contact position; a discrimination unit for determining the surface state of the medium transport belt; and a control unit for causing the cleaning means to perform the cleaning operation according to the surface state of the medium transport belt determined by the discrimination unit.

The invention discloses a terahertz detector and a preparation method thereof. The terahertz detector comprises a substrate; the TaNiTe5 layer is positioned on the substrate; the electrode is located on the substrate, and the electrode comprises a source electrode and a drain electrode which are electrically connected with the two ends of the TaNiTe5 layer respectively. According to the terahertz detector, the TaNiTe5 layer of the quasi-one-dimensional topological structure serves as the channel material layer of the terahertz detector, the unique double Dirac surface state and the quasi-one-dimensional structure of the TaNiTe5 layer can bring high carrier mobility, and effective detection of terahertz waves at the room temperature is achieved through a photoconductive response mechanism.

The application designs a material taking head control method, an unloading machine and electronic equipment. The material taking head control method comprises the following steps: determining a transverse movement speed and a feed amount of the material taking head based on an expected full load rate of the material taking head; and controlling the material taking head to take material according to the transverse movement speed and the feed amount, wherein the expected full load rate is a ratio of a material amount taken by the material taking head at the transverse movement speed and the feed amount to a full load material amount of the material taking head. In the embodiment of the application, the material taking head takes material at different transverse cutting speeds and feed amounts under different material surface states, thereby solving the problem of low material taking efficiency when the material taking head takes material at a fixed feed amount in the prior art.

The invention discloses a method for improving cleaning efficiency before electrogilding of a back hole. The method comprises the following steps: detecting components of a to-be-etched position on a wafer by using an EDS; an etching machine is used for etching the wafer to form a back hole, in the etching process, signal detection is continuously carried out on the surface of the wafer until a gold signal appears, an etching end point is taken, and the etching process is ended; an EDS is used for detecting a signal of the etched position of the wafer, and back hole components are detected; checking the surface state of the side wall of the back hole and the gold surface roughness of the etching stop layer by using an SEM (Scanning Electron Microscope), wherein the surface state of the side wall is a smooth state or a rough state; configuring a shower head according to the signal type; and cleaning the back hole by using a configured shower head according to the signal type, the side wall surface state and the gold surface roughness until the side wall surface state is a smooth state, and the signals of the etching position only comprise the gold signal and the signal from the semiconductor material. The process can be simplified, and the cleaning efficiency is improved.

An acoustic device includes a three-dimensional phononic crystal having cubic symmetry. The phononic crystal includes a first region filled with a first material and a second region filled with a solid material that is different from the first material. The second region is the solid complement of the first region. A boundary between the first and second regions is shaped as a single gyroid surface that has constant mean curvature and is not pinched off. The volume of the second region is greater than or equal to that of the first region. The first material may be a gas, such as air, or a fluid. The phononic crystal supports topological surface states, has a band structure with at least one degenerate point protected by nonsymmorphic symmetry, and exhibits negative refraction where two of its external surfaces meet.

To stably grow a regrowth layer.SOLUTION: A manufacturing method of a nitride crystal substrate includes the steps of: (a) preparing a substrate; (b) forming an intermediate layer including an n-type III-group nitride crystal above the substrate; (c) forming a cover layer including a III-group nitride crystal having a carrier concentration lower than that of the intermediate layer on the intermediate layer; (d) making the intermediate layer porous through a dislocation in the cover layer by electrochemical treatment while a surface state of the cover layer is maintained; (e) epitaxially growing a regrowth layer composed of a III-group nitride crystal on the cover layer; and (f) peeling the regrowth layer from the substrate at least at a part of a porous intermediate layer as a boundary. The step (e) has the steps of: (e1) growing a first regrowth layer on the cover layer at a first growth temperature; and (e2) growing a second regrowth layer on the first growth layer at a second growth temperature. The first growth temperature is lower than the second growth temperature at the step (e1).SELECTED DRAWING: Figure 1

The present invention provides an epitaxial layer structure of a doped InSb film and a preparation process thereof. Based on the MOCVD process, the InSb:Te layer and the InSb layer are periodically and alternately grown to form a doped InSb functional layer of a Hall element, which can increase the band gap of the InSb material and reduce the temperature coefficient of the InSb thin film Hall element; further, the epitaxial layer structure and preparation process provided by the present invention can achieve uniform doping and avoid excessive Te doping, and can reduce the defect density and surface state density of the doped InSb functional layer, thereby improving the sensitivity of the InSb Hall element and reducing the background noise of the Hall element. In addition, the epitaxial layer structure and preparation process of the doped InSb film provided by the present invention further improve the growth process, material and thickness of the buffer layer and the gradient layer, reduce the lattice mismatch between the substrate and the InSb film, reduce the dislocation density of the InSb film caused by the mismatch, and grow an InSb film with a higher mobility, thereby obtaining a higher sensitivity on the Hall element.

The invention relates to a surface modifier for a SiC semiconductor material as well as preparation and application of the surface modifier, and effective modification on the surface of the SiC material is realized through a specific chemical structure design. The modifier can significantly reduce the surface state density, improve the electron mobility and resistivity, and improve the surface hydrophobicity and stability. Compared with a traditional modification method, the method has innovativeness and advantages, and a new way is provided for performance improvement of the SiC semiconductor material.

The invention provides a method for manufacturing a nitride crystal substrate and a nitride crystal substrate. And the nitride crystal substrate containing AlGaN is stably obtained. This method for producing a nitride crystal substrate is provided with: (a) a step for preparing a base substrate; (b) forming an intermediate layer containing an n-type group III nitride crystal over the substrate; (c) forming, on the intermediate layer, a capping layer containing a group III nitride crystal having a carrier concentration lower than that of the intermediate layer; (d) maintaining the surface state of the cover layer by electrochemical treatment, and causing the intermediate layer to be porous by dislocation of the cover layer; (e) epitaxially growing a regrowth layer formed of a group III nitride crystal on the capping layer; (f) peeling off the regrowth layer from the substrate with at least a portion of the porous intermediate layer as a boundary, and in (e), growing, as the regrowth layer, a crystal represented by the compositional formula of AlxGa1-xN having an Al compositional ratio x of 0.05-0.8 (inclusive).

To provide a magnetic sensor that can improve heat resistance and reduce power consumption for magnetization reversal of a ferromagnetic material.SOLUTION: A magnetic sensor according to an embodiment includes a detection layer 901 including YPtBi, a non-magnetic half-Heusler alloy topological semimetal having a Dirac-type surface state and a spin Hall angle greater than 1, and a ferromagnet 902 in contact with the detection layer and having a magnetization oriented in the in-plane direction of a first surface in contact with the detection layer.SELECTED DRAWING: Figure 22

The invention relates to the technical field of photoelectric detectors and semiconductor materials, and particularly provides an all-inorganic lead-free two-dimensional perovskite single crystal as well as a preparation method and application thereof. According to the invention, N-ethyl-N-methylpiperidine iodized salt is introduced, and an improved cooling crystallization means of introducing a seed crystal is combined, so that the crystallization kinetics and the surface state of the lead-free two-dimensional perovskite are fundamentally changed; the problems of low crystal quality and poor X-ray detection and visible light detection device performance caused by poor growth controllability and multiple surface defects of the lead-free two-dimensional perovskite are solved. The obtained single crystal is large in size, low in defect density and smooth in surface, so that electrode contact and carrier extraction are facilitated. The performance of a detector based on the single crystal is greatly improved (the sensitivity of an X-ray detector reaches nearly 60000C. Gy <-1 >. Cm <-2 >, the responsivity of a visible light dual-mode detector exceeds 4000mA / W, and the response speed is within 1ms).

A system comprising a quantum information engine (QIE). The QIE includes a topological surface state three-dimensional topological insulator (TSS-3DTI) to flow, in a first flow direction from an input side to an output side, electrons having a first spin-momentum. The TSS-3DTI includes a first surface. The first surface has first spin-momentum locked charge carriers and a plurality of first magnetic impurities having a second average nuclear spin polarization. The TSS-3DTI stores information in the first surface at the points of interaction that occur between the plurality of first magnetic impurities interacting with the flowing electrons to exchange, at each point of interaction, a nuclear spin of a respective first magnetic impurity with an electron spin of a respective flowing electron. The system can include at least one surface. The system can harvest energy from other integrated circuits. A method of storing quantum energy is also provided.

The invention relates to the technical field of material detection, and provides a material detection method and system based on a photoacoustic effect. The material detection system comprises a light source for sending first detection light; the dispersion assembly is used for receiving the first detection light and obtaining second detection light after dispersion; the condensation assembly is used for focusing the second detection light on the surface of the to-be-detected material; the acquisition assembly is used for collecting acoustic signals; and the processor determines detection parameters of the to-be-detected material based on the sound wave signal, wherein the detection parameters comprise one or more of a material, a surface process, impurities or damage. According to the material detection system provided by the invention, the multi-wavelength photoacoustic response spectrum of the material can be captured by realizing single excitation through continuous wavelength, and the technical problem that a traditional detection system is easily interfered by environmental noise and material surface states due to adoption of a single signal is solved, so that the detection precision is effectively ensured, detection parameters are multi-dimensionalized, and the detection accuracy is improved. Various parameters of the to-be-detected material can be obtained, and the detection efficiency is improved.