Hitachi, Ltd.

Anelva Corporation

Katsuo Abe

Tsuneaki Kamei

Shigeru Kobayashi

Masao Sakata

Nobuo Nakagawa

Tsuneyoshi Kawahito

Kazuyuki Fujimoto

Yoshihiro Shiroishi

Masao Mitani

Naoki Kodama

Kenji Furusawa

Tokio Isogai

Susumu Aiuchi

Osamu Kasahara

Hidetsugu Ogishi

Tokuho Takagaki

Hiroyuki Kataoka

Hideaki Shimamura

Noriyuki Taguchi

Shigetoshi Hiratsuka

Hideki Tateishi

Hiroyuki Suzuki

Nobuyuki Takahashi

Yuzuru Hosoe

Akira Ikegami

Kiwamu Tanahashi

Masaaki Hayashi

Kazuetsu Yoshida

Yoshiki Kato

Yotsuo Yahisa

Tomoo Yamamoto

Shinji Narishige

Akira Ishikawa

Masaki Ohura

Takao Nakamura

Hiroshi Tani

Tsuneo Suganuma

Satoshi Matsunuma

Futoshi Tomiyama

Norikazu Tsumita

Hirayoshi Tanei

Katsuyuki Tanaka

Shigehiko Fujimaki

Akira Osaki

Muneo Mizumoto

Makoto Kitoh

Yuichi Kokaku

Nobuyuki Sugishita

Naoto Endo

Shinichi Hirose

Yoshihiro Sato

Emi Mangyo

Takao Yonekawa

Ryuji Sugimoto

Youichi Inoue

Hiroshi Ohtsu

Masashi Nakatsukasa

Takeshi Oyamada

Takao Edamura

In a magnetic recording system including magnetic recording media, a rotation driving unit for driving these magnetic recording media, read/write magnetic heads, driving apparatus for driving these read/write magnetic heads, and a read/write signal processing apparatus, a reading portion of the respective magnetic heads is arranged by a magnetoresistive head. The magnetic recording media are constructed of multi-layered magnetic media having a plurality of magnetic layers fabricated directly, or via underlayers on a non-magnetic disk substrate, and of non-magnetic intermediate layers arranged among these non-magnetic layers. Furthermore, one coercivity which is measured by applying a magnetic field along a circumferential direction of the magnetic recording media, is selected to be larger than the other coercivity which is measured by applying a magnetic field along a radial direction of the magnetic recording media, so that a higher signal-to-noise ratio is achieved, as compared with that of the conventional magnetic recording system. Since the thickness of the non-magnetic intermediate layers is smaller than or equal to 5 nm, and also the total layer is smaller than or equal to 5 nm, and also the total layer number of the plural magnetic layers is selected to be odd, better characteristics can be achieved. Accordingly, since the MTBF (Mean Time Before Failure) is longer than or equal to 0.15 million hours with high recording density, and the disk substrate and the magnetic head sliders can be mounted at high packaging density, a compact and high-capacity magnetic recording system can be obtained.

Multi-layered magnetic recording medium and magnetic recording system

A plasma processing apparatus comprising: a vacuum container; an evacuation means for keeping the interior of the vacuum container at a pressure not higher than atmospheric pressure; a substrate support device for supporting a substrate to be subjected to plasma processing; an electrode for generating plasma in cooperation with the substrate support; a voltage supply for applying a voltage to the electrode; a gas introducing system for introducing a gaseous material into a space where the plasma is produced; a surrounding member for enclosing the space above the substrate support, and a drive for relatively moving the surrounding member to space an end of the surrounding member proximate from the substrate from at least one of the substrate support and the substrate supported thereon by a distance which is short enough to suppress plasma leakage during the plasma processing and to position the end of the surrounding member away from said at least one of the substrate support and the substrate thereon for charging and discharging of the substrate.

Plasma processing method and apparatus

A magnetic recording medium and magnetic recording apparatus which can provide a high output level and a low noise level are disclosed. A magnetic recording medium includes a multilayer structure of magnetic alloy thin films containing Co, and at least one paramagnetic intermediate region or oxygen-rich region disposed between the magnetic layers. The intermediate region reduces the magnetic interaction between the magnetic layers without the degradation of crystallinity of the magnetic layers. As a result, a magnetic recording medium having such a structure shows low noise performance and a high recording density.

Magnetic recording medium and magnetic recording apparatus

The present invention provides a magnetic recording medium wherein the surface layer of the protective film of the medium is irradiated by ions to give a protective film having high reliability in resistance to sliding with the magnetic head, a process for producing the medium, an apparatus for producing the medium, and a magnetic recording apparatus having the medium mounted therein. The essentials of the present invention lie in introducing a minute surface roughness of atomic order in the surface of the protective film 5 constituting the outermost layer of a magnetic recording medium by irradiating atoms accelerated by high voltage (that is, by implanting ions) to the surface.

Magnetic recording medium, process for producing magnetic recording

The present invention relates to a magnetic recording medium for a magnetic disk unit or the like and, more particularly, to a magnetic recording medium having its recording layer made of a magnetic alloy film with uniform magnetic characteristics. The present magnetic recording medium comprises a non-magnetic substrate, at least two sputtered layers of chromium thin film having a bow-like columnar structure which chromium thin film is laminated on the substrate, another sputtered layer of a magnetic alloy thin film laminated on the chromium thin film, and a protective layer laminated on the magnetic alloy thin film. The present invention is effective in reducing modulation of regenerative output relatively independent of a texture roughness of the substrate.

Magnetic recording medium and method of producing same

A target for use in a sputtering technique usually has a flat structure. The present invention has succeeded in endowing sputtering film formation with a directivity in such a way that the surface of the target is provided with recesses thereby to limit the flight directions of sputtering particles. Alternatively, the directivity can be bestowed by disposing a frame between a substrate to be formed with a film and the flat sputtering target. This measure requires auxiliary means in which a wall is provided at the outer periphery of the sputtering target so as to effectively utilize a plasma. The present invention actually formed films by the use of the above technique, and has verified the effect thereof. Wide applications are expected in technical fields wherein after forming a microscopic pattern, one or more films need to be further formed.

Sputtering apparatus with film forming directivity

A sputtering target structure suitable for use with a planar magnetron sputtering electrode device has a plurality of annular target members arranged concentrically. The annular target member is provided with either an annular groove for concentration of an electric field or an annular wall for repelling electrons.

Target for sputtering

Planar magnetron sputtering sputters a target formed of plural target members from their principal surface. The plural target members are arranged on an electrode. The sputtering is carried out in such a condition that an electric field and magnetic field are substantially parallel in their direction at the boundary regions among the plural target members.

Planar magnetron sputtering with modified field configuration

Disclosed is a thermal printhead made of an insulating substrate, and a heat generating resistor layer formed on the substrate, and wherein the heat generating resistor layer is supplied with electric current. The heat generating resistor layer is made of Cr-Si-SiO alloy, and with the Cr, Si and SiO contents falling within a region defined by points A, B, C and D in a triangular diagram, where the points A, B, C and D are determined as follows:

Thermal printhead

Disclosed is a resistor made of an alloy consisting essentially of Cr, Si and SiO.

Resistor

A film forming method by plasma sputtering is provided to attain a composite film on a substrate. A target plate having metal materials in a different pattern is prepared in opposition to the substrate. A plasma is created by a planar magnetron sputtering electrode structure. The plasma is shifted magnetically on the target plate by at least three magnetically coupled magnetic poles to deposit the materials into a film with a uniform thickness and a desired composition on the substrate.

Film forming method

A base plate for magnetic recording disc is produced by coating thin metal layers containing no impurities for forming defects by an anodizing treatment on one or both sides of a discoid substrate made of a metal such as aluminum or an aluminum alloy or from a plastic by a dry process, and anodizing the thin metal layers so as to form anodized film from the surfaces of the thin metal layers to a certain depth while the portions contacting to the substrate are retained not anodized.

Base plate for magnetic recording disc

An apparatus for performing continuous treatment in vacuum including an inlet chamber, a first intermediate chamber, at least one vacuum treating chamber, a second intermediate chamber and a withdrawing chamber arranged in the indicated order in a direction in which base plates are successively transferred. An opening device normally closed and opened when a base plate is transferred therethrough is mounted on a wall at the inlet of the inlet chamber, between the adjacent chambers and on a wall at the outlet side of the withdrawing chamber. A conveyor device for conveying each base plate in a horizontal direction through the opening device is mounted in each of the chambers, and an evacuating device is also mounted in each chamber. A base plate storing device for storing a plurality of base plates in a magazine is mounted in the first and second intermediate chambers. At least one vacuum treating device is mounted in the vacuum treating chamber.

Apparatus for performing continuous treatment in vacuum

A sputtering apparatus of the planar magnetron type is disclosed, in which a low-pressure gas is ionized by glow discharge, ions in the plasma are accelerated by a voltage applied between a cathode and an anode to bombard a target structure, atoms or particles of a target material sputtered from the planar target plate by the bombardment of ions are deposited on a substrate disposed on the anode side, and thus a thin film made of the same material as the target material is formed on the substrate. In view of the facts that lines of magnetic flux generated by a single magnetic flux source does not link each other and the Maxwell stress, the target structure includes the planar target plate and a magnetic flux source having at least three pole pieces in an arrangement that the planar target plate is disposed between the anode and the magnetic flux source, and the amount of magnetic flux starting from a portion of the pole pieces is controlled to control the amount of magnetic flux (or the flux density) existing at the remaining pole pieces and the magnetic flux distribution above the planar target plate, thereby controlling the position of a region where the plasma is formed.

Sputtering cathode structure for sputtering apparatuses, method of

A low temperature-sinterable dielectric composition is provided, whose sintered composition when prepared by firing a uniform mixture consisting of lead ferrotungstate, lead titanate and manganese dioxide at a temperature of not higher than 1,000.degree. C. has the general formula A.Pb(Fe.sub.2/3 W.sub.1/3).sub.1-x Ti.sub.x O.sub.3 +B.MnO.sub.2, wherein 0.005.ltoreq..times..ltoreq.0.65, A=0.95-0.9995, and B=0.0005-0.05, a relative dielectric constant of at least 2,000 at 25.degree. C., a dissipation factor (tan .delta.) of not more than 5% at 25.degree. C., and a specific resistance of at least 10.sup.9 .OMEGA..cm at 25.degree. C. Also provided is a thick film capacitor having a dielectric layer prepared from said composition.

Low temperature-sinterable dielectric composition and thick film

Growing community of inventors

Yokosuka, Japan

Katsuo Abe