Aichi Steel Corporation

Shunichi Tatematsu

Michiharu Yamamoto

Akihiro Shimode

Ryusuke Yamashita

Norihiko Hamada

Koei Gemba

Shiori Itabuchi

A magneto-sensitive wire for a magnetic sensor with both measurement range expansion and environment resistance performance improvement, includes a Co-based alloy containing more Fe than a reference composition that is amorphous overall and exhibits zero magnetostriction. The Co-based alloy may have an Fe ratio (Fe/(Co+Fe+Ni)) of 6.1% to 9.5%. The Fe ratio is an atomic fraction of the Fe amount with respect to the total amount of a magnetic element group consisting of Co, Fe, and Ni. By heating an amorphous wire of a Co-based alloy at a temperate at least equal to a crystallization start temperature and lower than a crystallization end temperature, allows the magneto-sensitive wire to have a composite structure in which crystal grains are dispersed in the amorphous phase. The magneto-sensitive wire's anisotropy field is, for example, 5 to 70 Oe and the stress sensitivity, indicative of magnetostriction, is −30 to 30 mOe/MPa.

Magneto-sensitive wire and manufacturing method therefor

A magneto-impedance sensor element includes a magneto-sensitive body having electromagnetic properties that vary by a magnetic field externally acting thereon; and a detection coil wound around the magneto-sensitive body, in which a voltage corresponding to the intensity of the magnetic field acting on the magneto-sensitive body is output from the detection coil by applying a pulse current or a high-frequency current to the magneto-sensitive body. The magneto-sensitive body includes a first magneto-sensitive section and a second magneto-sensitive section that are configured to carry a pulse current or a high-frequency current in opposite directions to each other.

Magneto-impedance sensor element

An object is to provide a magneto-sensitive wire that exhibits a stable anisotropic magnetic field even under a high-temperature environment and can achieve expansion of the measurement range of an MI sensor, etc. The present invention provides a magneto-sensitive wire for magnetic sensors that comprises a Co-based alloy having a composite structure in which crystal grains are dispersed in an amorphous phase. The Co-based alloy contains 0.05 to 0.80 at %, preferably 0.10 to 0.60 at %, of Cu with respect to 100 at % of the Co-based alloy as a whole. The Co-based alloy may further contain 65 to 90 at % of the group of magnetic elements consisting of Co, Fe, and Ni as the total, 15 to 27 at % of Si and/or B as the total, and 0.5 to 2.5 at % of Mo. Such a magneto-sensitive wire is excellent in the heat resistance and exhibits a stable anisotropic magnetic field even under a high-temperature environment. By using the magneto-sensitive wire of the present invention, it is possible, for example, to efficiently produce an MI sensor with an expanded measurement range.

Magneto-sensitive wire for magnetic sensors and production method therefor

A method for etching an organic filmhaving a surface selectively protected by a hard mask layer, includes a partial etching process of etching the organic filmpartly in a thickness direction of the organic filmby using a mixed gas containing a gas that anisotropically etches a silicon oxide film and a gas that isotropically etches the organic film without etching the silicon oxide film; and a deposition process of depositing a protective filmmade of the silicon oxide film on side surfacesand a bottom surfaceof a recessformed in the organic film in the partial etching process. The partial etching process and the deposition process is alternately performed multiple times.

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Aichi, Japan

Shunichi Tatematsu