Neomax Co., Ltd.

Hitachi Metals, Ltd.

Taisuke Hirooka

Hironobu Tsubota

Hiroyuki Okuda

Shinji Tsujimoto

Hidetaka Sakumichi

A single-crystal silicon carbide substrate has a main surface having a surface roughness fulfilling Ra&#x2264;1 nm, and has a ratio of hidden scratches of less than 50%, where, in the case where the main surface is arbitrary observed at 50 or more observation points with a field of view having a diameter of 100 &#x3bc;m, the ratio of hidden scratches is defined by a value obtained by dividing the number of the observation points at which a striped hidden scratch having a length of at least 50 &#x3bc;m by the total number of the observation points.

Single-crystal silicon carbide substrate, method for producing single-crystal silicon carbide substrate, and method for inspecting single-crystal silicon carbide substrate

A method of manufacturing a SiC substrate which has a first principal surface and a second principal surface, includes the step of removing, by a vapor phase etching process, at least a portion of a work-affected layer which is formed by mechanical flattening or cutting on the first principal surface of the SiC substrate.

SiC substrate and method of manufacturing the same

A thin-film magnetic head substrate according to the present invention includes: a ceramic base with a principal surface; and an undercoat film, which covers the principal surface of the ceramic base. An electrical/magnetic transducer is provided on the undercoat film. The substrate further includes an intermediate layer between the principal surface of the ceramic base and the undercoat film. The intermediate layer is made of a material other than an aluminum oxide and has been patterned so as to make a portion of the principal surface of the ceramic base contact with the undercoat film.

Substrate with intermediate layer for thin-film magnetic head and method of manufacturing the substrate with intermediate layer

A method of manufacturing an SiC single crystal wafer according to the present invention includes the steps of: (a) preparing an SiC single crystal waferwith a mirror-polished surface; (b) oxidizing the surface of the SiC single crystal waferwith plasma, thereby forming an oxide layeron the surface of the SiC single crystal wafer; and (c) removing at least a portion of the oxide layerby a reactive ion etching process. Preferably, the surface of the wafer is planarized by repeatedly performing the steps (b) and (c) a number of times.

Method of manufacturing SiC single crystal wafer

A thin-film magnetic head wafer includes a first principal surface and a second principal surface which are substantially parallel to each other. An electrical/magnetic transducer is provided on the first principal surface. Identification information is recorded on the first principal surface of the wafer.

Thin film magnetic head wafer with identification information

A method for producing an alignment mark is performed such that the alignment mark can be removed from the surface of a substrate without leaving any trace thereof after the alignment mark has been used for alignment. After a first photoresist layer has been formed on a substrate, the first photoresist layer is subjected to patterning, and the alignment mark is thereby formed from the first photoresist layer. In the next step, after a second photoresist layer has been formed so as to cover the alignment mark, the second photoresist layer is subjected to patterning on the basis of the alignment mark. After the surface of the substrate has been subjected to etching by use of a resist mask thus formed, the resist mask and the alignment mark are removed, and the region where the alignment mark has been located is made flat.

Method for producing alignment mark

A substrate for a thin-film magnetic head includes a ceramic base and an undercoat film of amorphous SiC, which is supported on the ceramic base.

Substrate for thin-film magnetic head and method of manufacturing the substrate

A method of marking a sintered body includes the step of preparing the sintered body by sintering a mixture of first and second types of powder particles. The first type of powder particles is made of a first material and the second type of powder particles is made of a second material that has a different etch susceptibility from the first material. The method further includes the step of writing ID information on the surface of the sintered body by forming a first concave region to a depth of at least about 10 nm under the surface of the sintered body and a second concave region under the first concave region, respectively. The first concave region is formed by etching away both the first and second types of powder particles, while the second concave region is formed by etching away only the first type of powder particles.

Method of marking sintered body and method for manufacturing magnetic head wafer

Method for manufacturing a thin-film magnetic head wafer

A method of recording different identifiers, each including at least one character, on multiple plate-type members, involves the use of a photomask of a first type and at least two photomasks of a second type. The photomask of the first type has an opaque pattern that defines a blank region to write the identifier thereon. Each of the photomasks of the second type has an opaque pattern defining the at least one character. The method further includes the steps of forming a photoresist layer on the surface of one of the plate-type members, exposing the photoresist layer, except the blank region, to a radiation through the photomask of the first type, and forming a latent image of the at least one character in the blank region through at least one of the photomasks of the second type.

Method of recording identifier and set of photomasks

A method of recording identifiers, each including a group of character strings A and B including z, and zcharacters, respectively, on plate members involves the use of a photomask of a first type and at least one photomask of a second type. The photomask of the first type has an opaque pattern defining the character string A. The photomask of the second type has an opaque pattern defining at least one of the characters of the character string B. The method further includes the steps of forming a photoresist layer on one of the plate members, selectively exposing the photoresist layer to a radiation through the photomask of the first type to form a latent image of the character string A in the photoresist layer, and forming a latent image of the character of the character string B in the photoresist layer through the photomask of the second type.

A cleaning apparatus of an electronic component of the present invention comprises: means for supplying cleaning water to an object to be cleaned such as alumina titanium carbide wafer, a sponge member for contacting with the object to be cleaned to clean a surface thereof, means for moving the object to be cleaned and the sponge member relative to each other, and means for adjusting the resistivity value of the cleaning water to 10M&#x3a9; or less. Using this apparatus, the object to be cleaned is cleaned using the sponge member while supplying, to the object to be cleaned, cleaning water having the resistivity value of 10M&#x3a9; or less. In this case, the cleaning degree is enhanced by soaking the object to be cleaned in the water having the resistivity value of 10M&#x3a9; or less before cleaning, and by using a dummy substrate.

Growing community of inventors

Kobe, Japan

Taisuke Hirooka