Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Showa Denko K.k.

Hirokatsu Yashiro

Tatsuo Fujimoto

Jiro Ohno

Masakazu Katsuno

Masashi Nakabayashi

Hiroshi Tsuge

Takashi Aigo

Taizo Hoshino

Noboru Ohtani

Katsuhiko Yui

Hiroshi Nishikawa

Yoshiteru Matsuo

Hirotoshi Kawamura

Hiroaki Sakamoto

Kohei Tatsumi

Mitsuru Morita

Atsushi Kawasaki

Toshimi Tarui

Tohru Iuchi

Makoto Kosaka

Yukio Nakamori

Housei Hirano

Yoh-ichi Nagatake

The invention provides a low resistivity silicon carbide single crystal wafer for fabricating semiconductor devices having excellent characteristics. The low resistivity silicon carbide single crystal wafer has a specific volume resistance of 0.001 &#x3a9;cm to 0.012 &#x3a9;cm and 90% or greater of the entire wafer surface area is covered by an SiC single crystal surface of a roughness (Ra) of 1.0 nm or less.

Low resistivity single crystal silicon carbide wafer

Disclosed is a process for producing an epitaxial single-crystal silicon carbide substrate by epitaxially growing a silicon carbide film on a single-crystal silicon carbide substrate by chemical vapor deposition. The step of crystal growth in the process comprises a main crystal growth step, which mainly occupies the period of epitaxial growth, and a secondary crystal growth step, in which the growth temperature is switched between a set growth temperature (T) and a set growth temperature (T) which are respectively lower and higher than a growth temperature (T) used in the main crystal growth step. The basal plane dislocations of the single-crystal silicon carbide substrate are inhibited from being transferred to the epitaxial film. Thus, a high-quality epitaxial film is formed.

Process for producing epitaxial silicon carbide single crystal substrate and epitaxial silicon carbide single crystal substrate obtained by the same

An object of the present invention is to provide a production process of an epitaxial silicon carbide single crystal substrate having a high-quality silicon carbide single crystal thin film reduced in the surface defect and the like on a silicon carbide single crystal substrate with a small off-angle. According to the present invention, in the production process of an epitaxial silicon carbide single crystal substrate having a high-quality silicon carbide single crystal thin film reduced in the surface defect and the like on a silicon carbide single crystal substrate with an off-angle of 4&#xb0; or less, pretreatment etching to a depth of 0.1 to 1 &#x3bc;m is performed at a temperature of 1,550 to 1,650&#xb0; C. by flowing a gas containing silicon and chlorine together with a hydrogen gas such that the silicon atom concentration becomes from 0.0001 to 0.01% based on hydrogen atoms in the hydrogen gas, and thereafter, an epitaxial layer is formed.

Production process of epitaxial silicon carbide single crystal substrate

Provided is an epitaxial silicon carbide single-crystal substrate in which a silicon carbide epitaxial film having excellent in-plane uniformity of doping density is disposed on a silicon carbide single-crystal substrate having an off angle that is between 1&#xb0; to 6&#xb0;. The epitaxial film is grown by repeating a dope layer that is 0.5 &#x3bc;m or less and a non-dope layer that is 0.1 &#x3bc;m or less. The dope layer is formed with the ratio of the number of carbon atoms to the number of silicon atoms (C/Si ratio) in a material gas being 1.5 to 2.0, and the non-dope layer is formed with the C/Si ratio being 0.5 or more but less than 1.5. The resulting epitaxial silicon carbide single-crystal substrate comprises a high-quality silicon carbide epitaxial film, which has excellent in-plane uniformity of doping density, on a silicon carbide single-crystal substrate having a small off angle.

Epitaxial silicon carbide single crystal substrate and process for producing the same

A saw wire includes a steel wire () having a steel strand () with predetermined composition, an abrasive () fixed to the steel wire () by a fixing part (), and an intermetallic compound () on an interface between the abrasive () and the fixing part (). Tensile strength of the steel strand () is 3500 MPa or more, and the fixing part () includes a Sn-based solder containing Zn or Ag.

Saw wire

The invention provides a high-quality SiC single-crystal substrate, a seed crystal for producing the high-quality SiC single-crystal substrate, and a method of producing the high-quality SiC single-crystal substrate, which enable improvement of device yield and stability. Provided is an SiC single-crystal substrate wherein, when the SiC single-crystal substrate is divided into 5-mm square regions, such regions in which dislocation pairs or dislocation rows having intervals between their dislocation end positions of 5 &#x3bc;m or less are present among the dislocations that have ends at the substrate surface account for 50% or less of all such regions within the substrate surface and the dislocation density in the substrate of dislocations other than the dislocation pairs or dislocation is 8,000/cm.

SiC single-crystal substrate and method of producing SiC single-crystal substrate

Clinical thermometer

For measuring the sizes of particles in the falling state, electromagnetic waves having different frequencies are transmitted from a transmitter/receiver onto the particles in the falling state and reflected electromagnetic waves having different frequencies reflected from the particles in the falling state are received by the transmitter/receiver. Data of the distribution of sizes of the particles and the average size of the particles are derived from the detected intensities of the received reflected electromagnetic waves.

Measurement of sizes of falling particles

For measuring the sizes of particles in the falling state, electromagnetic waves having different frequencies are transmitted from a transmitter/receiver onto the particles in the falling state and reflected electromagnetic waves having different frequencies reflected from the particles in the falling state and received by the transmitter/receiver. Data of the distribution of sizes of the particles and the average size of the particles are derived from the detected intensities of the received reflected electromagnetic waves.

A method and apparatus for supervising a descending speed, thickness of a layer, particle size, and so on of charges in a blast furnace. Coke and ore composing the charges are detected by radiating an electromagnetic wave into the blast furnace. An electromagnetic wave can easily pass through coke, but is reflected or scattered by ore.

Method and apparatus for supervising charges in blast furnace using

A method of imaging the surface of an object at high temperature includes the steps of: irradiating the surface of a high-temperature object with two different kinds of pulses of monochromatic light of a fundamental wave and a harmonic thereof; passing the reflected light from the surface of the object through both an interference filter which allows only the two different kinds of monochromatic light to pass and a high-speed optical switch thereby to remove any background light component; drawing out only the reflected light of the pulses and leading the same to an image generating mechanism where it is converted into an image; and controlling the voltage applied to the high-speed optical switch thereby to adjust the mixing ratio between two wavelengths. Also disclosed is an apparatus for imaging the surface of an object at high temperature which includes: a light pulse generator provided such as to be opposed to high-temperature object; and an interference filter, a half-mirror, a high-speed optical switch and an image generating mechanism which are successively disposed on the optical axis of the reflected light from the object.

Method of and apparatus for imaging surface of object at high temperature

A method for measuring the water level in a well including the steps of radiating an electromagnetic wave to a gap between a boring drill rod and a casing pipe by using a transmitting antenna, receiving the electromagnetic wave reflected by a surface of the water level in the casing pipe by using a receiving antenna; then measuring a distance between the surface of the water level and the receiving antenna based on the going and returning time of the electromagnetic wave.

Growing community of inventors

Tokyo, Japan

Hirokatsu Yashiro