Fuji Electric Co., Ltd.

Toshiba Tungaloy Co., Ltd.

Hisashi Yamasaki

Tsutomu Mashimo

Susumu Yamaya

Minoru Nishida

Yuko Arimoto

Osamu Saito

Hiroyuki Uwazumi

Toyoji Ataka

Keiji Ohkubo

Kiyoto Yamaguchi

Takabumi Fumoto

Keiji Okubo

Yoshifumi Matsui

A thin film magnetic head includes an upper magnetic core film and a lower magnetic core film laminated one on another through a magnetic gap layer. The upper and lower magnetic core films are multilayer thin films, respectively, each of which is composed of a plurality of magnetic thin film layers and a plurality of non-magnetic thin film layers, alternately laminated one on another. The magnetic core films and have single domain structures, respectively, and the use of such magnetic core films realizes a thin film magnetic head having high permeability at high frequencies and improved high frequency characteristics and attains high recording density.

Thin film magnetic head

A magnetic recording medium includes a non-magnetic metal primary layer and a thin ferromagnetic alloy layer which are sequentially formed on a non-magnetic substrate in a laminated manner by sputtering. The thin ferromagnetic alloy layer is composed of not more than 15 at % of chromium, not more than 12 at % of platinum, 0.15 to 5.4 at % of a metal element selected from the group consisting of tantalum, hafnium, tungsten, zirconium and niobium, and the balance cobalt. The magnetic recording medium has a coercive force of higher than 1500 Oe and a squareness ratio of higher than 0.85.

Magnetic recording medium and a method for producing it

A thin-film magnetic head is disclosed that includes a lower magnetic core and an upper magnet core formed on the surface of a substrate and connected together at a first end thereof, a magnetic gap is formed between the lower and upper magnetic cores at a second end thereof, and a coil-form electric conductive layer is located between the lower magnetic core and the upper magnet core. The lower and upper magnetic cores have a saturated magnetic flux density from 10,000 G to 18,000 G, while the magnetic permeability along the magnetic path of the magnetic head is 3,000 or higher at a frequency of 10 MHz. The unique characteristics of the magnetic head are obtained by heating an arrangement comprising the lower and upper magnetic cores, the magnetic gap layer, and the electric conductive layer to a temperature above 325.degree. C., and applying an external magnetic field greater than 0.01 kOe to the lower and upper magnetic cores to relax their magnetic anisotropy as the lower and upper magnetic cores are cooled during the manufacturing process.

High permeability thin-film magnetic head and method of manufacture

The object of the present invention is to provide a stoichiometric B1-type tantalum nitride and a sintered body thereof. A B1-type tantalum nitride and a sintered body thereof, wherein a stoichiometric B1-type tantalum nitride is produced typically according to the method of impact compression, having the properties (a) that the X ray diffraction substantially shows a pattern ascribed to the stoichiometric B1-type tantalum nitride alone but not others, (b) that the measured value of the lattice spacing D (h, k, l) has a deviation of 0.00013 nm or less from the corresponding value calculated based on the B1 structure, (c) that the lattice constant is 0.4335.about.0.4338 nm, (d) that the electron diffraction image substantially shows the spots particular to the stoichiometric B1-type tantalum nitride alone but not others and (e) the value of Z in TaN.sub.z is within a range of 0.96-1.01.

Stoichiometric B1-type tantalum nitride and a sintered body thereof and

The object of the present invention is to provide a stoichiometric B1-type tantalum nitride and a sintered body thereof. A B1-type tantalum nitride and a sintered body thereof, wherein a stoichiometric B1-type tantalum nitride is produced typically according to the method of impact compression, having the properties (a) that the X-ray diffraction substantially shows a pattern ascribed to the stoichiometric B1-type tantalum nitride alone but not others, (b) that the measured value of the lattice spacing D (h, k, l) has a deviation of 0.00013 nm or less from the corresponding value calculated based on the B1 structure, (c) that the lattice constant is 0.4335.about.0.4338 nm, (d) that the electron diffraction image substantially shows the spots particular to the stoichiometric B1-type tantalum nitride alone but not others and (e) the value of Z in TaN.sub.z is within a range of 0.96-1.01.

Growing community of inventors

Kawasaki, Japan

Hisashi Yamasaki