10results about How to "Improve doping efficiency" patented technology

The invention discloses ZnO-based voltage-sensitive semiconductor ceramic as well as a preparation method and application thereof, and belongs to the technical field of semiconductor ceramic. The ZnO-based voltage-sensitive semiconductor ceramic provided by the invention is prepared from the following components: ZnO, Bi2O3, MnO2, Co3O4, Cr2O3, Sb2O3, Al (NO3) 3, a disulfide bond organic silicon cross-linking agent, a photothermal conversion agent, a photoinitiator, a dispersing agent and a solvent I. The ZnO-based voltage-sensitive semiconductor ceramic has the characteristics of continuous thickness and uniform components, the voltage gradient and the nonlinear coefficient of the ZnO-based voltage-sensitive semiconductor ceramic are superior to those of a traditional product, the parameter drift rate after surge impact is small, and the ZnO-based voltage-sensitive semiconductor ceramic can be applied to high-end application scenes such as vehicle-mounted chargers of new energy automobiles.

The invention discloses a heterojunction battery and a preparation method thereof. The preparation method comprises the steps of preparing the semiconductor substrate layer; preparing intrinsic amorphous silicon layers on two opposite surfaces of the semiconductor substrate layer respectively; depositing a doping layer on the intrinsic amorphous silicon layer; and manufacturing a transparent conductive layer on the doped layer. The preparation of the doping layer on the intrinsic amorphous silicon layer comprises the following steps: depositing a collection layer on at least one intrinsic amorphous silicon layer; a microcrystalline silicon layer is deposited on the collection layer, and carrier gas used in the process of depositing the microcrystalline silicon layer comprises argon. In this way, the deposition efficiency of the microcrystalline silicon layer and the photoelectric conversion efficiency of the heterojunction cell can be improved.

The application provides a semiconductor device and a manufacturing method thereof, and the semiconductor device comprises a substrate, a first gallium oxide bulk layer on the substrate, a gallium oxide epitaxial layer on the first gallium oxide bulk layer, wherein the gallium oxide epitaxial layer comprises a plurality of stacked structures, each of the stacked structures comprises a silicon-doped gallium oxide layer and a non-silicon-doped gallium oxide layer which are stacked, and a second gallium oxide bulk layer on the gallium oxide epitaxial layer. The gallium oxide epitaxial layer of the application comprises a plurality of stacked structures, each of the stacked structures comprises a silicon-doped gallium oxide layer and a non-silicon-doped gallium oxide layer which are stacked, and the gallium oxide bulk layers are respectively formed in front of and behind the gallium oxide epitaxial layer, so that the electron mobility of the gallium oxide epitaxial layer can be effectively improved, the doping efficiency is improved, the crystal quality of the gallium oxide epitaxial layer is improved, and the gallium oxide epitaxial layer is widely applied in the field of power devices.

The present application relates to a kind of methods for preparing fluorescent nitrogen-rich carbon quantum dots from coal in aqueous system based on photocatalytic technology, belonging to the technical field of nanomaterial preparation.The method includes pretreatment of coal, ammonia oxidation reaction of coal and ammonia water to obtain nitrogen-rich soluble, the nitrogen-rich soluble is subjected to photocatalytic reaction again, and finally, carbon quantum dot solid powder is prepared by centrifugation, filtration, dialysis and drying treatment.The present application realizes the preparation of fluorescent nitrogen-rich carbon quantum dots from low-rank coal in aqueous system by using ammonia oxidation and photocatalytic technology, and the reaction conditions are mild and green and non-toxic, without harsh reaction conditions such as high temperature / high pressure, strong acid / strong base environment, organic solvent or special equipment.

The application discloses a growth method of a high-carrier-concentration heavily doped gallium oxide epitaxial film, and mainly solves the problems of high cost, high defect density and low carrier concentration of a currently used heavily doped epitaxial film substrate. The implementation scheme is as follows: a sapphire substrate is selected and cleaned; the cleaned substrate is put into a reaction cavity of a MOCVD (Metal Organic Chemical Vapor Deposition) for pretreatment; two layers of buffer layers with different mechanisms are sequentially grown on the substrate by changing the temperature, pressure and ratio of reaction sources of the reaction chamber; a Ge heavily doped beta-Ga2O3 film with an epitaxial concentration of 10 19 cm ‑3 -10 20 cm ‑3 is epitaxially prepared on the second buffer layer by using a pulse MOCVD method with GeH4 as a dopant and a catalyst, and the epitaxial film is annealed, so that the preparation of the epitaxial film is completed. The defect density of the epitaxial film and the substrate use cost are reduced, and the carrier concentration is improved, so that the epitaxial film can be used for the preparation of power devices and switching devices.

This invention discloses a low-indium ceramic target, its preparation method, and its application. The low-indium ceramic target comprises the following components by mass percentage: indium oxide content of 50.2%–60.8%; zinc oxide content of 16.8%–25.3%; tin oxide content of 18.0%–28.3%; and metal oxide content of 0.10%–2.5%. The sum of the contents of all components is 100%. The metal oxide includes at least three of the following: praseodymium oxide, hafnium oxide, terbium oxide, dysprosium oxide, and cerium oxide. Increasing the density of the target and lowering the sintering temperature improves the mobility of the TCO thin film prepared from the low-indium ceramic target.

The invention belongs to the technical field of fuel cells, and provides an aperture-adjustable sulfur-nitrogen co-doped mesoporous carbon material for a fuel cell and a preparation method and application thereof.The preparation method comprises the steps that organic magnesium salt, a polyhydroxy compound capable of being fused and gelatinized at the temperature of 200-300 DEG C and a compound containing sulfur and nitrogen element compound-urea are used as raw materials; after dissolving and uniformly mixing, carrying out heating polymerization and microwave-assisted uniform dispersion; gradually converting the mixed solution into a uniform gel precursor along with the volatilization of the solvent; and grinding into powder, carrying out three-section gradient carbonization program heating carbonization treatment under the protection of inert atmosphere, and removing the template through acid pickling to obtain the target product. According to the present invention, the directional adjustment of the mesopore size and the pore size distribution is achieved, and by using the mesoporous structure as the fuel cell cathode catalyst carrier, the mass transfer path can be effectively optimized by using the high specific surface area and the adjustable mesoporous structure, and the oxygen reduction reaction activity, the polarization performance and the long-term stability can be significantly improved.

The invention relates to the technical field of high-purity boron-doped silicon carbide powder and a solid-phase synthesis method thereof, and particularly discloses high-purity boron-doped silicon carbide powder and a solid-phase synthesis method thereof. The invention aims to solve the problems that the boron doping concentration is uncontrollable, the component distribution is uneven, the impurity content is high and the powder particle size does not meet the crystal growth requirement of a physical vapor transport method in the existing preparation of the p-type silicon carbide single crystal raw material. The method comprises the following steps: mixing high-purity carbon powder, silicon powder and a boron source in proportion; the preparation method comprises the following steps: firstly, generating silicon carbide crystal nucleuses at the constant temperature of 1350-1500 DEG C under the protection of inert gas filled after vacuum, and then promoting grain growth and uniform doping of boron at the constant temperature of 2100-2300 DEG C and 13.3-66.7 kPa; and cooling, crushing, screening, cleaning and drying to obtain target powder. By the adoption of the technical scheme, precise regulation and control of the boron doping concentration ranging from 0.01 at% to 5 at%, customized growth with the particle size ranging from 0.1 mm to 3 mm and high cleanliness with the purity higher than 99.999% can be achieved, the powder fluidity is good, and the requirements for growth of high-performance p-type silicon carbide single crystals and application of high-thermal-conductivity ceramic substrates are completely met.

The utility model discloses a doping device for heavily doping a Czochralski single crystal, which comprises a doping bowl suitable for containing a dopant, a doping device for heavily doping a Czochralski single crystal, and a doping device for heavily doping a Czochralski single crystal, the doping cover comprises a doping cover body and a guide part, the doping cover body is bell-shaped, the axial direction of the doping cover body extends in the vertical direction, the doping bowl is coaxial with the doping cover body and is connected with the top of the inner wall of the doping cover body, and the guide part is connected to the bottom end of the doping cover body; the guide part is annular and extends outwards and downwards in the radial direction of the doping cover body, and the guide part and the silicon solution are arranged at an interval in the vertical direction. Therefore, the guide part is connected to the bottom of the doping cover body, so that on the premise of ensuring non-contact doping, the guide part can block and guide a part of escaping gas molecules, the doping area can be increased, the doping efficiency can be improved, and the one-time yield of single crystal growth can be improved.

This invention provides an alkali-activated synergistic nitrogen-phosphorus co-doped porous biomass hard carbon material, its preparation method, and its application. This invention only requires mixing pre-carbonized biomass material, an activator, and a dopant, followed by calcination under an inert atmosphere to obtain a porous hard carbon material. Then, the porous hard carbon material is calcined again under an inert atmosphere to obtain the alkali-activated synergistic nitrogen-phosphorus co-doped porous biomass hard carbon material. This simple and effective method achieves the stepped pore design and nitrogen-phosphorus doping of the hard carbon material, and the obtained nitrogen-phosphorus co-doped porous hard carbon material exhibits high specific capacity and initial coulombic efficiency.