139 results about "Vacancy defect" patented technology

The present invention provides aluminum oxide crystalline materials including dopants and oxygen vacancy defects and methods of making such crystalline materials. The crystalline materials of the present invention have particular utility in optical data storage applications.

A single crystal synthetic CVD diamond material comprising: a growth sector; and a plurality of point defects of one or more type within the growth sector, wherein at least one type of point defect is preferentially aligned within the growth sector, wherein at least 60% of said at least one type of point defect shows said preferential alignment, and wherein the at least one type of point defect is a negatively charged nitrogen-vacancy defect (NV⁻).

A single crystal CVD synthetic diamond material comprising: a total as-grown nitrogen concentration equal to or greater than 5 ppm, and a uniform distribution of defects, wherein said uniform distribution of defects is defined by one or more of the following characteristics: (i) the total nitrogen concentration, when mapped by secondary ion mass spectrometry (SIMS) over an area equal to or greater than 50×50 μm using an analysis area of 10 μm or less, possesses a point-to-point variation of less than 30% of an average total nitrogen concentration value, or when mapped by SIMS over an area equal to or greater than 200×200 μm using an analysis area of 60 μm or less, possesses a point-to-point variation of less than 30% of an average total nitrogen concentration value; (ii) an as-grown nitrogen-vacancy defect (NV) concentration equal to or greater than 50 ppb as measured using 77K UV-visible absorption measurements, wherein the nitrogen-vacancy defects are uniformly distributed through the synthetic single crystal CVD diamond material such that, when excited using a 514 nm laser excitation source of spot size equal to or less than 10 μm at room temperature using a 50 mW 46 continuous wave laser, and mapped over an area equal to or greater than 50×50 μm with a data interval less than 10 μm there is a low point-to-point variation wherein the intensity area ratio of nitrogen vacancy photoluminescence peaks between regions of high photoluminescent intensity and regions of low photolominescent intensity is <2× for either the 575 nm photoluminescent peak (NV⁰) or the 637 nm photoluminescent peak (NV); (iii) a variation in Raman intensity such that, when excited using a 514 nm laser excitation source (resulting in a Raman peak at 552.4 nm) of spot size equal to or less than 10 μm at room temperature using a 50 mW continuous wave laser, and mapped over an area equal to or greater than 50×50 μm with a data interval less than 10 μm, there is a low point-to-point variation wherein the ratio of Raman peak areas between regions of low Raman intensity and high Raman intensity is <1.25×; (iv) an as-grown nitrogen-vacancy defect (NV) concentration equal to or greater than 50 ppb as measured using 77K UV-visible absorption measurements, wherein, when excited using a 514 nm excitation source of spot size equal to or less than 10 μm at 77K using a 50 mW continuous wave laser, gives an intensity at 575 nm corresponding to NV⁰ greater than 120 times a Raman intensity at 552.4 nm, and/or an intensity at 637 nm corresponding to NV⁻ greater than 200 times the Raman intensity at 552.4 nm; (v) a single substitutional nitrogen defect (N_s) concentration equal to or greater than 5 ppm, wherein the single substitutional nitrogen defects are uniformly distributed through the synthetic single crystal CVD diamond material such that by using a 1344 cm⁻¹ infrared absorption feature and sampling an area greater than an area of 0.5 mm², the variation is lower than 80%, as deduced by dividing the standard deviation by the mean value; (vi) a variation in red luminescence intensity, as defined by a standard deviation divided by a mean value, is less than 15%; (vii) a mean standard deviation in neutral single substitutional nitrogen concentration of less than 80%; and (viii) a colour intensity as measured using a histogram from a microscopy image with a mean gray value of greater than 50, wherein the colour intensity is uniform through the single crystal CVD synthetic diamond material such that the variation in gray colour, as characterised by the gray value standard deviation divided by the gray value mean, is less than 40%.

The present invention provides a composition for forming a liquid crystal alignment film, which comprises a photoreactive polymer including a multicyclic compound having a photoreactive group on a main chain thereof. The present invention also provides a liquid crystal alignment film produced using the composition, and a liquid crystal display including the liquid crystal alignment film. The photoreactive polymer including the multicyclic compound on the main chain thereof has a high glass transition temperature, thus thermal stability is excellent. Since lattice vacancy is relatively large, the photoreactive group is capable of moving relatively freely in the main chain of the polymer, thus it is possible to improve a slow photoreaction rate, which is considered a disadvantage of a conventional polymer material.

Technologies are generally described for perforated graphene monolayers and membranes containing perforated graphene monolayers. An example membrane may include a graphene monolayer having a plurality of discrete pores that may be chemically perforated into the graphene monolayer. The discrete pores may be of substantially uniform pore size. The pore size may be characterized by one or more carbon vacancy defects in the graphene monolayer. The graphene monolayer may have substantially uniform pore sizes throughout. In some examples, the membrane may include a permeable substrate that contacts the graphene monolayer and which may support the graphene monolayer. Such perforated graphene monolayers, and membranes comprising such perforated graphene monolayers may exhibit improved properties compared to conventional polymeric membranes for gas separations, e.g., greater selectivity, greater gas permeation rates, or the like.

A food handling system having a vacancy reduction system. The vacancy reduction system includes the main conveyor, a food product parking station, a vacancy detector, a robot, and a controller. The vacancy detector is configured to detect a vacant food product position on the main conveyor. The robot has a working range for moving between the parking station and the main conveyor. The controller is signal-connected to the vacancy detector. The controller is configured to receive a signal from the vacancy detector indicating a vacant food product position on the conveyor. The controller is signal-connected to the robot and has control instructions for instructing the robot to move the food product from the food product parking station to the vacant food product position on the main conveyor.

A wafer is characterized in that the wafer has a non-uniform distribution of crystal lattice vacancies, wherein the concentration of crystal lattice vacancies in the bulk layer are greater than the concentration of crystal lattice vacancies in the front surface layer. In addition, the front surface of the wafer has an epitaxial layer, having a thickness of less than about 2.0 μm, deposited thereon. A process comprises heating a surface of a wafer starting material to remove a silicon oxide layer from the surface and depositing an epitaxial layer onto the surface to form an epitaxial wafer. The epitaxial wafer is then heated to a soak temperature of at least about 1175° C. while exposing the epitaxial layer to an oxidizing atmosphere comprising an oxidant, and the wafer is cooled at a rate of at least about 10° C./sec.

A semiconductor device comprises a semiconductor substrate, a first electrode formed on a first main surface of the semiconductor substrate, and a second electrode formed on a second main surface of the semiconductor substrate. The semiconductor substrate includes a first region in which a density of oxygen-vacancy defects is greater than a density of vacancy cluster defects, and a second region in which the density of vacancy cluster defects is greater than the density of oxygen-vacancy defects.

The invention provides a rapid-annealing method for growing large-size sapphire single-crystal with the SAPMAC method. The SAPMAC method is adopted for growing sapphire single-crystal; after growing is finished, the vacuum degree of a crystal growing furnace is kept; electric power source is not cut off; heating power is lowered according to certain temperature reduction procedure until heating power is zero; and then inert gases are led in for rapid cooling. The invention has the beneficial effects that: 1. crystal dislocation density can be lowered, the lattice vacancy of crystal with big diameter and high expansion factor can be lowered, defect concentration such as distortion of lattice, dislocation and the like can be eliminated, crystal cleavage is avoided, and crystal quality and utilization factor can be improved; 2. in-situ annealing of crystal can be realized, crystal growing cycle can be shortened under the precondition of ensuring crystal quality; and 3. production cost can be lowered.

The present invention improves upon the Czochralski method for growing a single-crystal silicon ingot and provides a high quality silicon wafer having an oxide layer with superior voltage-resistance characteristics. An apparatus and method are also provided, whereby vacancy defect density and distribution are uniformly controlled. A single-crystal silicon ingot is grown under a condition where the temperature variation of the ingot is less than or equal to 20° C./cm in the temperature range of 1000 to 1100° C.

The invention belongs to the technical field of photocatalysis, and discloses a surface oxygen vacancy defect modified bismuth tungstate photocatalyst, and a preparation method and applications thereof. The preparation method comprises following steps: a sodium tungstate precursor solution and a bismuth nitrate precursor solution are mixed to obtain a bismuth tungstate precursor solution, ultrasonic treatment is carried out, the bismuth tungstate precursor solution is introduced into a high temperature reaction vessel with a conductive substrate, hydro-thermal reaction is carried out at 100 to180 DEG C, deionized water is adopted for washing, under nitrogen gas flow, drying is carried out, sintering is carried out at 450 to 600 DEG C, and an obtained bismuth tungstate film grows on the flat conductive substrate is subjected to heat processing at 150 to 400 DEG C at reductive atmosphere to obtain a finished product. The surface of the obtained surface oxygen vacancy defect bismuth tungstate film possesses more active sites, so that higher photoelectric conversion efficiency is achieved; and at the same time, existing of oxygen vacancy defects is capable of realizing micro adjustingof forbidden bandwidth Eg of the bismuth tungstate photocatalyst, narrowing Eg, and obtaining wider visible light response range.

The invention relates to a preparation method of two-dimensional bismuth oxygen selenium atom crystals. The method comprises the following steps that a precursor containing bismuth elements and selenium elements is subjected to physical vapor deposition, a two-dimensional bismuth oxygen selenium atom crystal material is obtained, and the two-dimensional bismuth oxygen selenium atom crystal material is a tetragonal system. By adopting physical vapor deposition, the problem that the ratio of a bismuth source to a selenium source is not easily controlled in the chemical gas-phase reaction processis solved, the obtained two-dimensional bismuth oxygen selenium atom crystal material is higher in purity, vacancy defects are less, then, the electronic mobility is higher, the electronic mobility is larger than or equal to 135 cm<2>/(V s), meanwhile, compared with chemical vapor deposition, the physical vapor deposition can enable the crystal form integrity of the two-dimensional bismuth oxygenselenium atom crystal material to be higher, the crystal size is larger, the single crystal domain edge can reach the millimeter scale, the maximum single crystal domain edge is not smaller than 1.7mm, and the minimum signed crystal domain edge is not smaller than 200 micrometers.

The present invention is directed to a single crystal Czochralski silicon wafer having a non-uniform distribution of lattice vacancies with peak concentration at a hypothetical In the bulk of the wafer between the central plane and a surface, such that after a heat treatment cycle in essentially any electronic device manufacturing process, the wafer forms oxygen precipitates in the bulk and a thin or shallow no-sedimentation zone.

The invention relates to an in-situ preparation method of photocatalyst strontium bismuth niobium oxide containing an oxygen vacancy defect. The method comprises the following steps of adopting a molten-salt growth method to synthesize a SrBi2Nb2O9 nanosheet, putting the SrBi2Nb2O9 nanosheet at H2 atmosphere, using ultraviolet-visible-infrared light for full-spectrum illumination, and obtaining SrBi2Nb2O9-VO. Compared with a traditional method that the oxygen vacancy defect is produced by calcining a sample at inert atmosphere or reducing atmosphere, the method for producing the oxygen vacancy defect provided by the invention is simpler, more effectively, lower in required cost, and favorable to take full advantage of sunlight. According to the method, not only can the oxygen vacancy defect be in-site produced on a catalyst, but also the catalyst can utilize the produced oxygen vacancy defect for improving the own performance in photocatalytic reducing CO2. Meanwhile, the method is hopefully applied in other oxygenous Bi-based photocatalysts.

The invention provides a modified transition metal base-layer dihydroxy compound nano material, which comprises two or three transition metals, and further comprises an atomic level cation vacancy defect, the atomic level cation vacancy defect is a vacancy defect left by removing of one of the transition metals. The invention also provides a preparation method of the nano material through complexation reaction, and the preparation method can selectively remove designated metal ions to controllably form the atomic level cation vacancy defect at the atomic level, and has simple operation and mild reaction. The nano material and a water decomposition catalyst and a water decomposition electrode containing the nano material show lower decomposition water overpotential and faster hydrogen production rate, and have wide application prospect in efficient and cheap large-scale commercial water decomposition hydrogen production.

A semiconductor device and a formation method therefor are disclosed. The formation method for the semiconductor device comprises the steps of providing a substrate including a first region and a second region; forming a groove including a first part and a second part in the substrate; forming a first barrier layer at the bottom of the first part and the surface of the side wall of the groove, wherein the first barrier layer captures lattice vacancy defects or interstitial atom defects in the substrate; forming a second barrier layer at the bottom of the second part and the surface of the side wall of the groove, wherein the second barrier layer captures lattice vacancy defects or interstitial atom defects in the substrate, and defect types captured by the first barrier layer and the second barrier layer are different; forming dielectric layers for filling the grooves; forming a first well region in the first region substrate; forming a second well region in the second region substrate, wherein the doping types of the second well region and the first well region are opposite. According to the semiconductor device and the formation method therefor, the diffusion of the doping ions in the first well region and the second well region can be effectively prevented to endow the semiconductor device with a good electrical isolation performance.

A photoconductor includes a conductive substrate, an undercoat layer on the substrate, and at least one photosensitive layer on the undercoat layer. The radius of vacancy type defects in each of the photosensitive layer and in the undercoat layer is o.4 nm or less. In one embodiment, the radius of vacancy type defects is measured by a positron annihilation method.

The invention relates to the technical field of nano processing, in particular to a method for processing a graphene superlattice nano-structure with an atomic force microscope. The method for processing the graphene superlattice nano-structure with the atomic force microscope comprises the steps that a manual vacancy defect is formed on graphene in the mode of applying pulse voltages to a needle point of the atomic force microscope, and then anisotropic etching is carried out on the graphene through a hydrogen-contained plasma. According to the method, nano hole array patterns with a period smaller than a 200 nm can be achieved on the graphene. The period of the graphene superlattice nano-structure and nanoribbon width are controllable. A processing method of the needle point of the atomic force microscope is simple and free of inducing additional pollution means, and an obtained device is clean. In addition, with the assistance of the needle point array processing technology, the method can be used for device integration and mass production of graphene nano-structure devices.