Home > 사업분야
To Be The Lead Of Global Business Inteligence Service
The recording form of the magnetic recording material is divided into two types: 1. longitudinal magnetic recording material, and the magnetization direction of the signal recorded on the surface of the magnetic layer coincides with the moving direction of the recording material, such as an audio tape. 2.transverse magnetic recording material, the direction of signal magnetization recorded on the surface of the magnetic layer is perpendicular to or close to the direction of movement of the recording material, such as a video tape. 3 perpendicular magnetic recording material, the direction of signal magnetization recorded on the surface of the magnetic layer is perpendicular to the surface of the recording material, such as a magneto-optical disk.
Since the development of magnetic recording materials, the recording wavelength has been shortened from the initial 1000 μm to less than 1 μm, and the Hc has been increased from 102 Oe to more than 103 Oe. The most widely used materials are oxide magnetic powder (mainly Γ-Fe2O3, CrO2 and cobalt-coated magnetic powder) and alloy magnetic powder.
In the past 20 years, the material performance has been improved from the following three ways to meet the requirements of high-density recording:
1 Seeking to improve magnetic anisotropy, such as ultra-fine particle, high-axis ratio needle-shaped magnetic powder, CrO2 and cobalt-coated magnetic powder and Hc>1000Oe New materials such as alloy magnetic powder.
2 thinning the magnetic layer and improving the coating technology to improve Hc and achieve high density recording. It is common to use both oxygen removal and adhesive removal. The former is replaced by metal powder, and the latter is made into a film. The alloy film is the result of the combination of the two methods.
3 Make fundamental improvements from the recording principle and recording mode. At present, when the density is increased in the general longitudinal recording, the generated demagnetizing field can reduce the signal and generate a vertical component. This method can be overcome by increasing the Hc and thinning the magnetic layer, but there are certain limits.
Therefore, a perpendicular recording material appears, and the demagnetizing field generated by it tends to zero as the density increases. And vertical recording does not require high Hc and very thin materials. Effectively overcomes the Achilles heel of longitudinal recording at high density recording. Vertical recording requires that the material have uniaxial anisotropy on the surface of the perpendicular magnetic layer.
Since 1975, the Co-Cr vertical film and the subsequent Co-Cr and Ni-Fe double-layer films, which have been successfully developed by Japan's Yan Duan Jun, are new materials that can adapt to vertical recording. In 1977, Iwasaki announced the results of a linear density of 7.9 kilobits per centimeter (20 kilobits per inch), while the linear density of hard disks has so far not exceeded 5.9 kilometers per centimeter (15 kilobits per inch). Toshiba Corporation of Japan has manufactured 8.9cm (3.5in) vertical floppy disk, and recently developed a barium ferrite perpendicular magnetization video tape. The magnetic powder used is hexagonal plate-shaped barium ferrite ultrafine particles, and the recording density is 2 times higher than that of ordinary video tape. Especially in terms of short-wavelength recording, its characteristics are superior to metal tape.
As a new type of perpendicular magnetic recording material, iron-cobalt-tantalum-zirconium perpendicular magnetic recording material will have broad development prospects in future high-density recording. The picture below are two micrographs of our FeCoTaZr alloy sputtering target, the average grain size＜50μm.
We produce FeCoTaZr alloy sputtering target, it’s most important benefits is that in the process of PVD, the higher permeability can make the target sputtering smoothly and obtain the film with the smallest particles with uniform grains.Below form is a typically certificate of analysis for 3N5 high purity CoFeTaZr sputtering target.
The analytical methods used are: 1. Analysis of metal elements using ICP-OES; 2. Analysis of gas elements using LECO. 3.The permeability was tested using permeability tester.