Tanaka Kikinzoku Kogyo K.k.

Tohoku University

Ryousuke Kushibiki

Yasuyuki Goto

Masahiro Nishiura

Masahiro Aono

Takanobu Miyashita

Takamichi Yamamoto

Kim Kong Tham

Toshiya Yamamoto

Shin Saito

Shintaro Hinata

Yasunobu Watanabe

A CoPt-oxide-based in-plane magnetized film having a magnetic coercive force of 2.00 kOe or more and remanent magnetization per unit area Mrt of 2.00 memu/cmor more. The in-plane magnetized film for use as a hard bias layer of a magnetoresistive element contains metal Co, metal Pt, and an oxide. The in-plane magnetized film contains the metal Co in an amount of 55 at % or more and less than 95 at % and the metal Pt in an amount of more than 5 at % and 45 at % or less relative to a total of metal components of the in-plane magnetized film, and contains the oxide in an amount of 10 vol % or more and 42 vol % or less relative to a whole amount of the in-plane magnetized film. The in-plane magnetized film has a thickness of 20 nm or more and 80 nm or less.

In-plane magnetized film, in-plane magnetized film multilayer structure, hard bias layer, magnetoresistive element, and sputtering target

Provided is a sputtering target with which it is possible to form a magnetic thin film having a high coercive force Hc. The sputtering target is a sputtering target that contains metallic Co, metallic Pt, and an oxide, wherein the sputtering target contains no metallic Cr except inevitable impurities, the oxide has BO, and the sputtering target comprises 10 to 50 vol % of the oxide.

Sputtering target

A sputtering target for magnetic recording media capable of producing a magnetic thin film in which the magnetic crystal grains are micronized and the distance between the centers of the grains is reduced while good magnetic properties are maintained. The target including metallic Pt and an oxide, with the balance being metallic Co and inevitable impurities, wherein the Co is contained in a range of 70 at % to 90 at % and the Pt is contained in a range of 10 at % to 30 at % relative to a total of metallic components in the sputtering target for magnetic recording media, the oxide is contained in a range of 26 vol % to 40 vol % relative to a total volume of the sputtering target for magnetic recording media, and the oxide is composed of BOand one or more high-melting-point oxides having a melting point of 1470&#xb0; C. or higher and 2800&#xb0; C. or lower.

Sputtering target for magnetic recording media

Through the present invention, a thin film containing an FePt-based alloy and carbon, the thin film being capable of being used as a magnetic recording medium, is enabled to be formed using one target, and amount of particles is enabled to be reduced. An FePt&#x2014;C-based sputtering target containing Fe, Pt, and C, wherein the FePt&#x2014;C-based sputtering target has a structure in which a C phase substantially being C is dispersed in an FePt-based alloy phase containing 33 mol % or more and 60 mol % or less of Pt with the balance substantially being Fe, an average value of the size indices a of the C phase is 4.0 &#x3bc;m or more and 9.0 &#x3bc;m or less, and an average value of the nonspherical indices b of the C phase is 3.0 or more.

FePt-C-based sputtering target

An FePt&#x2014;C-based sputtering target containing Fe, Pt, and C, wherein the FePt&#x2014;C-based sputtering target has a structure in which primary particles of C that contain unavoidable impurities are dispersed in an FePt-based alloy phase containing 33 at % or more and 60 at % or less of Pt with the balance being Fe and unavoidable impurities, the primary particles of C being dispersed so as not to be in contact with each other.

FePt&#x2014;C-based sputtering target and method for manufacturing same

An FePt-based sputtering target contains Fe, Pt, and a metal oxide, and further contains one or more kinds of metal elements other than Fe and Pt, wherein the FePt-based sputtering target has a structure in which an FePt-based alloy phase and a metal oxide phase containing unavoidable impurities are mutually dispersed, the FePt-based alloy phase containing Pt in an amount of 40 at % or more and less than 60 at % and the one or more kinds of metal elements in an amount of more than 0 at % and 20 at % or less with the balance being Fe and unavoidable impurities and with the total amount of Pt and the one or more kinds of metal elements being 60 at % or less, and wherein the metal oxide is contained in an amount of 20 vol % or more and 40 vol % or less based on the total amount of the target.

FePt-based sputtering target

A process for producing an FePt-based sputtering target includes adding C powder containing unavoidable impurities and metal oxide powder containing unavoidable impurities to FePt-based alloy powder containing Pt in an amount of 40 at % or more and 60 at % or less with the balance being Fe and unavoidable impurities so that the C powder and the metal oxide powder are contained to satisfy:0&#x3c;&#x3b1;&#x2266;20;10&#x2266;&#x3b2;&#x3c;40; and20&#x2266;&#x3b1;+&#x3b2;&#x2266;40,

Process for producing FePt-based sputtering target

A process for producing an FePt-based sputtering target includes adding metal oxide powder containing unavoidable impurities to FePt-based alloy powder containing Pt in an amount of 40 at % or more and less than 60 at % and one or more kinds of metal elements other than Fe and Pt in an amount of more than 0 at % and 20 at % or less with the balance being Fe and unavoidable impurities and with a total amount of Pt and the one or more kinds of metal elements being 60 at % or less so that the metal oxide powder accounts for 20 vol % or more and 40 vol % or less of a total amount of the FePt-based alloy powder and the metal oxide powder, followed by mixing the FePt-based alloy powder and the metal oxide powder to produce a powder mixture.

An FePt&#x2014;C-based sputtering target contains Fe, Pt, and C and has a structure in which an FePt-based alloy phase and a C phase containing unavoidable impurities are mutually dispersed, the FePt-based alloy phase containing Pt in an amount of 40 at % or more and 60 at % or less with the balance being Fe and unavoidable impurities. The content of C is 21 at % or more and 70 at % or less based on the total amount of the target.

FePt-C-based sputtering target and process for producing the same

An FePt-based sputtering target has a structure in which an FePt-based alloy phase, a C phase containing unavoidable impurities, and a metal oxide phase containing unavoidable impurities are mutually dispersed, the FePt-based alloy phase containing Pt in an amount of 40 at % or more and 60 at % or less with the balance being Fe and unavoidable impurities, wherein C is contained in an amount of more than 0 vol % and 20 vol % or less based on the total amount of the target, the metal oxide is contained in an amount of 10 vol % or more and less than 40 vol % based on the total amount of the target, and the total content of C and the metal oxide is 20 vol % or more and 40 vol % or less based on the total amount of the target.

Growing community of inventors

Tsukuba, Japan

Ryousuke Kushibiki