90 results about "Ferrite thin films" patented technology

A ferrite film is formed by regularly arranging constituents such as magnetized grains or one analogous to that. In the ferrite film, the constituents have at least one of the uniaxial anisotropy and the multiaxial anisotropy. The ferrite film has the magnetic anisotropy or the magnetic isotropy. The ferrite film is formed by the use of the plating method in the presence of a magnetic field. Furthermore, an electromagnetic noise suppressor includes the ferrite film.

A self-biased giant magneto-impedance sensor probe and a preparation method thereof belong to the technical field of information functional devices. The probe comprises an amorphous strap-shaped magnetic material and metal counter electrodes positioned at two ends of the surface of the amorphous strap-shaped magnetic material, wherein two vectolite films are respectively deposited on two sides of the amorphous strap-shaped magnetic material between the metal counter electrodes; and the upper and the lower vectolite films have consistent hard magnetic phase characteristic in the length direction of the amorphous strap-shaped magnetic material. During preparation of the probe, the key process is that the vectolite films are deposited on the amorphous strap-shaped magnetic material through the radio-frequency magnetron sputtering technology and are magnetized through a magnetizer to present hard magnetic phase. The self-biased giant magneto-impedance sensor probe provided by the invention has the characteristics of small size, easiness in integration and no extra power consumption; the product is simple to prepare, the process is controllable and the stability is high; and a wider linear working space can be obtained and the sensitivity is greatly improved.

A magneto-optical device (MOD) with optically induced magnetization for use in magnetic field sensors as a magnetic element pinning a magnetization in a preferred direction of a ferromagnetic layer as well as a magnetic memory cell for magneto-optical recording. The MOD comprises the Mg—Mg—Co ferrite film deposited on a magnesium oxide (MgO) substrate. The ferrite film is illuminated at room temperature with a circularly polarized light (CPL) in a static magnetic H-field (about of 3 kOe) normal to the illuminated ferrite film surface. At certain (“writing”) combinations of H, sigma (CPL helicity), the long-lived optically induced magnetization with a unidirectional anisotropy, stable to a conventional demagnetization occurs. For readout of information, conventional magnetoresistive sensors and MFM can be used. To erase information, the ferrite film should be illuminated with two field-light combinations, other than “writing”, or annealed at temperature higher than 530 degrees C.

[Task] To provide a method of forming a ferrite thin film in which it is possible to manufacture a thick film having a film thickness of 1 µm or more using a sol-gel method without causing cracking. [Means for Resolution] A method of forming a ferrite thin film by carrying out a process for forming a coated film by coating a ferrite thin film-forming composition on a heat-resistant substrate and a process for calcining the coated film once or a plurality of times so that the thickness of the calcined film on the substrate becomes a desired thickness, and firing the calcined film formed on the substrate, in which the conditions for firing the calcined film formed on the substrate are under the atmosphere or an oxygen gas or inert gas atmosphere, a temperature-rise rate of 1°C / minute to 50°C / minute, a holding temperature of 500°C to 800°C, and a holding time of 30 minutes to 120 minutes.

The invention relates to a preparation method of a nanometer strontium ferrite thin film, which is characterized in that the invention is made through the following steps: iron nitrate, strontium nitrate, and the like, mainly serve as raw materials to prepare a forerunner body of the nanometer strontium ferrite in a sol-gel method; clean silicon dioxide serves as a support base, the iron nitrate and the strontium nitrate salt, citric acid serves as complexing agent, glycol serves as complexing agent assist, the silicon dioxide support base is arranged in the forerunner body, namely is soaked in the sol, and a soakage-drawing method is adopted to make the film. The preparation method of a nanometer strontium ferrite thin film has the characteristics that firstly, the sol-gel method is adopted to prepare, and the nanometer thin film with high purity is obtained through optimizing preparation technology, and basic components of the nanometer strontium ferrite thin film can be seen in a table 2; secondly, the grain size of the nanometer strontium ferrite thin film is 40mm to 60mm, the grain size is evenly distributed, and the thin film surface is compact and is composed of bar-shaped crystal particles which are stacked; thirdly, the electromagnetic performance of the nanometer strontium ferrite thin film is good.

A ferrite material is disclosed, consisting of an oxide metal composition, the metal composition having the formula of FeaNibZncCod, where: a+b+c+d=3.0; 2.1<=a<=2.7; 0<=b<=0.4; 0<=c<=0.4; and 0.1<=d<=0.5. A ferrite film is made of the ferrite material. Preferably, the ferrite film is formed by a ferrite plating method to have a thickness of 30 mum or less and an aspect ratio of 30 or more. The ferrite film is arranged or provided in the vicinity of an antenna conductor of a radio frequency identification tag. The ferrite film may be in direct contact with the antenna conductor.

Disclosed is a method for manufacturing a manganese zinc ferrite film through a sol-gel method. The method comprises the steps that 1, ferric nitrate and zinc nitrate are weighed according to the Mn<0.5>Zn<0.5>Fe<2>O<4> stoichiometric proportion, and the two raw materials are dissolved in deionized water; 2, a manganous nitrate solution is added to a solution obtained in the step 1, citric acid is added as a complexing agent, and a mixed solution is obtained; 3, ammonia water is added to the mixed solution obtained in the step 2, the pH value of the solution is adjusted to range from six to seven, sol is obtained, and then polyvinylpyrrolidone is added in the sol; 4, a silicon substrate is washed through a hydrochloric acid and hydrofluoric acid mixed aqueous solution and is blow-dried through nitrogen; 5, the manganese zinc ferrite sol obtained in the step 3 is dropped on the silicon substrate washed in the step 4, a KW-4A spin coater is used for whirl coating by 2,000-3,000 r / min, the sol is evenly distributed on the surface of the silicon substrate, then after the silicon substrate is placed in a muffle furnace of 250 DEG C to 300 DEG C for heat treatment for 20-30 min, the silicon substrate is heated to 500 DEG C along with the furnace, and the silicon substrate is taken out after heat preservation is kept for 20-30 min. the temperature rise rate along with the furnace is 10-20 DEG C / min, and the furnace temperature change is within + / -5 DEG C.