38results about How to "Room temperature ferromagnetic" patented technology

This invention relates to a method for preparing BiFeO3-based multifunctional oxide ceramic. The method comprises: (1) pre-pressing BLTFO8 powder into a disc, loading oxide protective powder (Al2O3, CeO2, ZrO2 or FeO) into a graphite mold, and pressing; (2) transferring the BLTFO8 disc onto the oxide protective powder layer in the mold; (3) continuing adding oxide protective powder into the mold to embed the BLTFO8 disc, and pressing; (4) transferring the mold into an SPS sintering furnace, heating to 600 deg.C within 3 min, then heating to the sintering temperature at a rate of 50 deg.C/min, keeping the temperature, and sintering. Since BiFeO3 has G-type antiferromagnetic structure, doping with rare earth element such as La or Tb, or metal element such as Ba or K can alter its antiferromagnetic structure, and the obtained BiFeO3-based multifunctional oxide ceramic has ferromagnetism at room temperature. The method can inhibit the valency change of the elements and reduce loss, and the BiFeO3-based multifunctional oxide ceramic has good ferroelectric and ferromagnetic properties at room temperature.

The invention discloses a Ga2o3/(Ga1-xFex)2o3 film with room temperature ferromagnetism and high ultraviolet light permeation function and the manufacturing method thereof. The film is provided with room temperature ferromagnetism, a high penetration rate in deep ultraviolet zones and the ability for high energy photons to penetrate. The film can be used in researches on the mutual effect of high energy photon spinning and electron spinning. The manufacturing method for the film is performed as follows: using a c face sapphire as a substrate; conducting cycle deposition for a plurality of times to a Ga2o3 thin layer and a transitional metal Fe thin layer through a laser molecular beam epitaxial technology, and achieving a multi-layer film of Ga2o3/(Ga1-xFex)2o3 doped with transitional metal elements through the heat diffusion among the layers. The manufacturing method for the multi-layer film enables a Ga2o3/(Ga1-xFex)2o3 film to be doped by different amounts of Fe by adjusting the times for laser pulse of a Fe deposition layer. The entire process is done in the same cavity so the purity of a sample is guaranteed. Further, since the equipment is commonplace, it can be conveniently promoted for wide use. The Ga2o3/(Ga1-xFex)2o3 film manufactured by the invention is a diluted magnetic semiconductor material with great prospects for future use.

The invention provides a method for preparing a Fe-doped ZnO room temperature diluted magnetic semiconductor material, which adopts a coprecipitation method and includes: A. prepare a mixed solution of Fe<3+> and Zn<2+> and a NaOH solution; B. mix the mixed solution of Fe<3+> and Zn<2+> and the NaOH solution to form a precipitate, then filter, separate and wash the precipitate; C. dry, pre-sinter, grind, tablet and sinter the precipitate to obtain the Fe-doped ZnO room temperature diluted magnetic semiconductor material. The invention provides a completely new method for preparing the Fe-doped ZnO room temperature diluted magnetic semiconductor material and the Fe-doped ZnO room temperature diluted magnetic semiconductor material prepared by the method has room temperature ferromagnetism.

The invention discloses a method for preparing a ZnO nanowire with an adulteration of ferromagnetic Fe under a room temperature, which belongs to the field of semiconductor nanometer material preparation technology; a method of vapor deposition is adopted by the invention to carry out an original position adulteration in the process of preparing the ZnO nanowire; ZnO, C, and Fe powder are provided as evaporation sources, silicon chip is provided as a receiving lining which is placed on a corundum boat and positioned right above the evaporation and has a vertical distance of 2-4mm with the evaporation source. Then, all materials are put in a pipe typed stove where 300-350 ml/min argon is inlet; after 5-8 min, flow rate of the argon is changed to 120-160ml/min; the pipe typed stove is heated to a temperature of 950-1050 DEG C, with an internal pressure of the stove maintained at 0.03-0.05Mpa; heat preservation for 140-160 min, the stove is naturally cooled to the room temperature, thus obtaining the large scale of well distributed ZnO nanowire with the adulteration of Fe. The method solves the problem of reasonably adulterating magnetic element Fe to the ZnO nanowire; the obtained ZnO nanowire with the adulteration of ferromagnetic Fe has ferromagnetism under a room temperature. The method has the advantages that the raw materials are cheap; the technique is simple; the energy consumption is low; the productivity is high; the product is pollution free to the environment and is applicable to an industrialized production.

This invention relates to a semiconductor film material preparation technology of zn1-xCoXo with the ferromagnetic property (namely Zno doped with Co, x is the orthonormal atomic number ratio of Co atoms and Zn atoms, which applies a commercial electronic beam reaction vapor system and uses multi-crystal Zno powder and Co, Co2o3 or Co3O4 powder as the material to be grown on the surface of the substrate directly. Apart from the main doped element Co, it does not need any other sub- doped elements, besides, its Curie temperature is higher then the room one, the preparation technology is rather simple.

This invention provides a preparation method for TiO2 film doped with Co for a room temperature ferro-magnetic semiconductor, which applies a sol-gel method to prepare Co doped TiO2 sol and coats the sol on a substrate of a monocrystal silicon to form a CoxTi1-xO2 film to be annealed and crystallized directly under the vacuum to have the ferromagnetic property, in which, said film does not have the property of room temperature in air, it must be annealed secondly in vacuum or He atmosphere.

The invention discloses a preparation method of an Si-doped AlN diluted magnetic semiconductor film, which uses high-purity nitrogen as work gas, high-purity Al targets and silicon wafers are adopted for in-situ co-sputtering, the background vacuum degree of a system is 10<-5>Pa to 10<-4> Pa, a substrate is n type Si(100), the distance from the targets and the substrate is 60mm, the sputtering power is 300W, the sputtering air pressure is 1.5Pa, and the substrate temperature is 370 DEG C, and the sputtering time is 60min. After the substrate is cleaned, and surface impurities are removed, the AlN diluted magnetic semiconductor film with different doping concentrations are obtained through changing the number of the doping silicon wafers. The method has the advantages that the preparation deposition velocity is high, the process is simple, and in addition, the diluted magnetic semiconductor film materials with the room temperature ferromagnetism and high Curie temperature can be obtained without any subsequent treatment, so the method has important study value and wide application prospects.

The invention relates to a growing method for no polarity ZnO crystal thin films. The pulsed laser deposition is adopted. Firstly, ZnO, MnO2 and Na2CO3 fine powder are weighted and ground in a ball way, pressed and sintered to obtain ceramic target co-doped with Mn-Na; and then the pulsed laser deposition is used for growing the no polarity ZnO crystal thin films on an under layer. The method has the advantages of mature technique, simple operation, low cost, and easy implementation. The grown thin film has a axis preferred orientation, has room temperature ferromagnetism, is a dilute magnetic semiconductor and can be applied to LEDs and memory devices.

the invention discloses a preparing method of indoor-temperature magnetic Zn1-xMnxO nanometer line in the rare-magnetic semiconductor nanometer material preparing domain, which comprises the following steps: cleaning silicate through HCl and acetone; adopting Zn powder and MnCl2 powder and evaporating source in the adjacent quartz ship; making silicate as receiving substrate at intersecting part of two evaporating source vertically; setting the vertical distance between silicate and evaporating source at 6-8 mm; placing quartz ship in the pipe-typed furnace; aerating gas in the system inlet; conducting gas in the water through rubber conduct; aerating argon gas at 300-400ml/min for 5-8 min; changing the flow of argon gas at 30-50 ml/min; heating the pipe-typed furnace at 800-830 deg.c; maintaining the system pressure at atmospheric condition; keeping temperature for 120-150 min; cooling to indoor temperature naturally to obtain the even-distributing Zn1-xMnxO nanometer line.

The invention discloses copper-doped aluminum nitride base diluted magnetic semiconductor nano rods and a preparation method thereof. The preparation method comprises the following steps of: mixing aluminum chloride and copper chloride uniformly in a certain molar ratio; and then performing ammoniation on the mixture in an ammonia atmosphere to obtain the Cu-doped aluminum nitride directly. The copper-doped aluminum nitride base diluted magnetic semiconductor nano rod has the advantages of simple method, low equipment requirement, high ferromagnetism of the prepared AIN:Cu, a Curie temperature higher than the room temperature, and good application prospect, and can be applied for nano spintronics devices, such as a spin field effect tube (spin-FET), a spin light-emitting diode (spin-LED) and the like.

The invention relates to a vanadium doped titania nanometer dilute magnetic semiconductor and a preparation method thereof, wherein, the reparation method includes the steps that: A, the predecessor body solution of vanadium ion and the predecessor body solution of titanium ion are prepared; B, the two solutions are mixed to form sol; C, the sol is aged under room temperature to form wet gel, and the wet gel is dried in an oven until dry gel is formed; D, the dry gel is skived to obtain dry gel powder, and the dry gel powder removes organic matter through heat treatment in atmosphere; the dry gel powder annealings in inert atmosphere to be made into the nanometer powder of the vanadium doped titania dilute magnetic semiconductor. The vanadium doped titania nanometer dilute magnetic semiconductor made by the method of the invention forms a power shape, and can show the room temperature ferromagnetism.

The invention relates to a preparation method of rock-salt mine structure Co-doped CdS diluted magnetic semiconductor nanoparticles, and belongs to the technical field of preparation of diluted magnetic semiconductor nano-particle materials. The preparation method comprises the following steps: taking sphalerite structure Co-doped CdS diluted magnetic semiconductor nanoparticles as initial raw materials, keeping the pressure for 30-50min under the conditions that the pressure is 5.0-7.0GPa and the temperature is 600-800 DEG C, and performing cooling and pressure relief to obtain the rock-salt mine structure Co-doped CdS diluted magnetic semiconductor nanoparticles. According to the preparation method disclosed by the invention, the high-temperature and high-pressure method is utilized to synthesize the rock-salt mine structure Co-doped CdS diluted magnetic semiconductor nanoparticles; the forbidden bandwidth of a rock-salt mine CdS diluted magnetic semiconductor is 1.5-1.7eV; furthermore, the rock-salt mine CdS diluted magnetic semiconductor is an indirect band gap semiconductor and formed by combining the rock-salt mine structure with the sphalerite structure, and the band gap can change continuously within the whole spectral region from near ultraviolet light to far infrared light; and simultaneously, the rock-salt mine structure Co-doped CdS diluted magnetic semiconductor nanoparticles have room temperature ferromagnetism and thus become ideal materials for various optoelectronic and magneto-optical devices.

The invention relates to a Cu-doped-ZnO nano columnar crystal film with room-temperature ferromagnetism and a preparing method of the Cu-doped-ZnO nano columnar crystal film. The chemical formula of the film is Zn<1-x>Cu<x>o, wherein x is larger than or equal to 0.01 but smaller than or equal to 0.1. The film has the room-temperature ferromagnetism. The microstructure of the film is in a columnar crystal form within the nano scale range, and columnar structures are evenly distributed and arranged orderly. The microstructure of the Cu-doped-ZnO nano columnar crystal film is in the columnar crystal form within the nano scale range, on one hand, the film has the light guiding performance and electrical conductance performance in the preferential direction, and on the other hand, the film has a larger specific surface area; and accordingly the film of this type has superior magnetoelectric performance and magneto-optic performance.

The invention relates to a SiC-based diluted magnetic semiconductor thin film and a preparation method thereof. The method comprises the following step of irradiating a SiC thin film material with a certain dosage of carbon particles <12>C<+>, thereby preparing the SiC-based diluted magnetic semiconductor thin film. The SiC thin film after being processed according to the method has obvious room-temperature ferromagnetism, is relatively high in saturation magnetization, and has favorable potential application value. The method is stable and effective, and the SiC-based diluted magnetic semiconductor thin film material can be prepared on the premise of no damage to the material.

A diluted magnetic semiconductor thin film material appears many novel physical properties, and the novel physical properties provide a broader space for development of novel spin-based devices, so that the diluted magnetic semiconductor thin film material has broad application prospects in the fields of magnetic inductors, high-density non-volatile memories, optical isolators, semiconductor laser devices, spin quantum computers and the like, and has become one of research hot spots in the field of the materials. Traditional methods for preparing thin film materials comprise a molecular beam epitaxy method, a metal organic matter chemical vapor deposition method and the like, and the methods are balanced growth methods and have the shortcomings of low doping efficiency, high equipment maintenance cost, expensive price of raw materials, long production period, complex tail gas treatment process and the like. The invention belongs to the technical field of semiconductors and provides a method for preparing a GaMnN diluted magnetic semiconductor thin film material, and the method has the advantages of high doping efficiency, low preparation cost, short production period, simple tail gas treatment and the like, and can greatly improve the production efficiency and economic benefits.