Nippon Steel Corporation

Sharp Kabushiki Kaisha Corporation

Nippon Steel Sumitomo Metal Corporation

Kwansei Gakuin Educational Foundation

Mitsubishi Gas Chemical Company, Inc.

Toyo Tanso Co., Ltd.

Noboru Ohtani

Tatsuo Fujimoto

Masashi Nakabayashi

Mitsuru Sawamura

Yoshiyuki Masuda

Tadaaki Kaneko

Masakazu Katsuno

Masayoshi Koba

Ryusuke Kita

Hiroshi Tsuge

Kenta Hagiwara

Masahiko Ishikawa

Hirokatsu Yashiro

Yoshitaka Masuda

Yoshiya Kimura

Takatoshi Matsumura

Hisako Arai

Yoshiyuki Matsu

Takeshi Kijima

Noriyuki Kato

Jun Takahashi

Seiki Yano

Kohei Tatsumi

Satoru Nogami

Hironori Matsunaga

Ayumu Adachi

Yutaka Unuma

Manabu Fujimoto

Sakiko Satoh

Taizo Hoshino

David Heard

Shoji Ushio

Masatoshi Kanaya

Yuichiro Fujiwara

Kyoko Nishizaki

Housei Hirano

In this method for manufacturing a semiconductor element, a modified layer produced by subjecting a substrate () to mechanical polishing is removed by heating the substrate () under Si vapor pressure. An epitaxial layer formation step, an ion implantation step, an ion activation step, and a second removal step are then performed. In the second removal step, macro-step bunching and insufficient ion-implanted portions of the surface of the substrate () performed the ion activation step are removed by heating the substrate () under Si vapor pressure. After that, an electrode formation step in which electrodes are formed on the substrate () is performed.

Method for manufacturing silicon-carbide semiconductor element

This method for treating a surface of a SiC substrate includes a first removal step in which a modified layer produced by subjecting the substrate () to mechanical polishing or chemical-mechanical polishing is removed by heating the substrate () under Si vapor pressure. A second removal step in which macro-step bunching occurred in an epitaxial layer () is removed by heating the substrate () under Si vapor pressure may also be performed. Since the etching rate can be varied, etching rate in the first removal step is high, so that the modified layer can be removed in a short time. Meanwhile, etching rate in the second removal step is comparatively low, so that excessive removal of the epitaxial layer () can be prevented.

Method for treating the surface of a silicon-carbide substrate including a removal step in which a modified layer produced by polishing is removed by heating under Si vapor pressure

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

The invention provides an apparatus for manufacturing good quality single-crystal silicon carbide stably without formation of cracks and the like, which apparatus comprises: at least a crucible for accommodating silicon carbide feedstock powder and seed crystal; heat insulation material installed around the crucible; and a heating device for heating the crucible, wherein the outer profile of the crucible includes at least one region of narrower diameter than a vertically adjacent region, insulation material is also installed in the space left by the diameter difference, and thickness of the insulation material at the narrower diameter region is greater than that of the insulation material at the vertically adjacent region. The apparatus for manufacturing single-crystal silicon carbide enables precise control of the temperature gradient inside the crucible, thereby enabling manufacture of good quality single-crystal silicon carbide.

Apparatus for manufacturing single-crystal silicon carbide

A method for manufacturing a semiconductor wafer includes a carbon layer formation step, a through hole formation step, a feed layer formation step, and an epitaxial layer formation step. In the carbon layer formation step, a carbon layer () is formed on a surface of a substrate () made of polycrystalline SiC. In the through hole formation step, through holes () are formed in the carbon layer () formed on the substrate (). In the feed layer formation step, a Si layer () and a 3C&#x2014;SiC polycrystalline layer () are formed on a surface of the carbon layer (). In the epitaxial layer formation step, the substrate () is heated so that a seed crystal made of 4H&#x2014;SiC single crystal is formed on portions of the surface of the substrate () that are exposed through the through holes (), and a close-spaced liquid-phase epitaxial growth of the seed crystal is caused to form a 4H&#x2014;SiC single crystal layer.

Semiconductor wafer manufacturing method, and semiconductor wafer

Disclosed is a light-transmitting electromagnetic-shielding laminate, which is characterized in that two or more layers including an electromagnetic-shielding layer are arranged in layers using a (meth)acrylate adhesive composition which contains a (meth)acrylate monomer, a (meth)acrylate oligomer and at least one member selected from the group consisting of acrylic amide derivatives, silane compounds and organophosphorus compounds. Also disclosed is a light-transmitting radio wave absorber which is characterized in that a resistive layer, a dielectric spacer and a reflective layer are arranged in layers using a (meth)acrylate adhesive composition which contains a (meth)acrylate monomer, a (meth)acrylate oligomer and at least one member selected from the group consisting of acrylic amide derivatives, silane compounds and organophosphorus compounds.

Light-transmitting electromagnetic-shielding laminate and method for producing the same, light-transmitting radio wave absorber, and adhesive composition

Provided is a monocrystalline silicon carbide ingot containing a dopant element, wherein a maximum concentration of the dopant element is less than 5&#xd7;10atoms/cmand the maximum concentration is 50 times or less than that of a minimum concentration of the dopant element. Also provided is a monocrystalline silicon carbide wafer made by cutting and polishing the monocrystalline silicon carbide ingot, wherein a electric resistivity at room temperature of the wafer is 5&#xd7;10&#x3a9;cm or more. Further provided is a method for manufacturing the monocrystalline silicon carbide including growing the monocrystalline silicon carbide on a seed crystal from a sublimation material by a sublimation method. The sublimation material includes a solid material containing a dopant element, and the specific surface of the solid material containing the dopant element is 0.5 m/g or less.

Monocrystalline silicon carbide ingot, monocrystalline silicon carbide wafer and method of manufacturing the same

The present invention provides a high resistivity, high quality, large size SiC single crystal, SiC single crystal wafer, and method of production of the same, that is, a silicon carbide single crystal containing uncompensated impurities in an atomic number density of 1&#xd7;10/cmor more and containing vanadium in an amount less than said uncompensated impurity concentration, silicon carbide single crystal wafer obtained by processing and polishing the silicon carbide single crystal and having an electrical resistivity at room temperature of 5&#xd7;10&#x3a9;cm or more, and a method of production of a silicon carbide single crystal.

Silicon carbide single crystal, silicon carbide single crystal wafer, and method of production of same

The present invention provides a light-transmitting electromagnetic wave-shielding material for use in displays or in-vehicle panels each having a polarizing plate or a retardation plate, wherein the light-transmitting electromagnetic wave-shielding material undergoes no generation of light interference fringes and is satisfactory in visibility even through sunglasses, goggles, glare-proof panels or glare-proof window materials having polarizing capability. By using unstretched light-transmitting organic polymer materials low in molecular orientation or small in molecular orientation unevenness as the base substrate of an electromagnetic wave-shielding layer, the light-transmitting electromagnetic wave-shielding material excellent in light interference fringe prevention capability can be obtained.

Light-transmitting electromagnetic wave-shielding material

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

The present invention provides a single-crystal silicon carbide ingot capable of providing a good-quality substrate low in dislocation defects, and a substrate and epitaxial wafer obtained therefrom. It is a single-crystal silicon carbide ingot comprising single-crystal silicon carbide which contains donor-type impurity at a concentration of 2&#xd7;10cmto 6&#xd7;10cmand acceptor-type impurity at a concentration of 1&#xd7;10cmto 5.99&#xd7;10cmand wherein the concentration of the donor-type impurity is greater than the concentration of the acceptor-type impurity and the difference is 1&#xd7;10cmto 5.99&#xd7;10cm, and a substrate and epitaxial wafer obtained therefrom.

Single-crystal silicon carbide ingot, and substrate and epitaxial wafer obtained therefrom

The present invention provides a semi-insulating silicon carbide single crystal characterized by having an electrical resistivity at room temperature of 1&#xd7;10&#x3a9;cm or more, and a semi-insulating silicon carbide single crystal characterized by having an electrical resistivity at room temperature of 1&#xd7;10&#x3a9;cm or more and vacancy pairs (bivacancies), and an semi-insulating silicon carbide single crystal characterized by having an electrical resistivity at room temperature of 1&#xd7;10&#x3a9;cm or more and containing a crystal region where a position average lifetime becomes a lifetime longer than 155 ps in measurement of position lifetime at a liquid nitrogen boiling point temperature (77K) or less, and wafer obtained therefrom. According to the present invention, by having vacancy clusters including vacancy pairs, the electrical conductivity can be reduced even when the nitrogen concentration is higher than the boron concentration and, in addition, a semi-insulating SiC single crystal resistant to change of the electrical conductivity even with heat treatment can be obtained.

Silicon carbide single crystal and single crystal wafer

Growing community of inventors

Sanda, Japan

Noboru Ohtani