Sumitomo Electric Industries, Limited

Kabushiki Kaisha Komatsu Seisakusho

Nec Corporation

Komatsu Corporation

Seiko Epson Corporation

Hiroyuki Kitabayashi

Hideaki Nakahata

Kenjiro Higaki

Satoshi Fujii

Shin-ichi Shikata

Koji Katayama

Youichi Nagai

Tomoki Uemura

Kentaro Yoshida

Yuichiro Seki

Tadayuki Ishikawa

Hideto Tamaso

Ikuo Kamada

Yoshiaki Kuroda

Shin-Ichi Shikata

Yasushi Yamamoto

Katsushi Akita

Keiji Wada

Takashi Kyono

Yusuke Yoshizumi

Yoshihiro Takahashi

Taku Horii

Shinichi Shikata

Hirohisa Saito

Mitsuhiko Sakai

Toshiyuki Ooenoki

Satoshi Arakawa

Masashi Narita

Ayako Ikeda

Natsuhiko Sakairi

Hiroyuki Kuroda

Yoshihiko Nakakoji

Masaki Nobuhara

In accordance with the following step of a method of manufacturing a MOSFET, a first cutting step of cutting a silicon carbide wafer along a plane substantially parallel to a {11-20} plane is performed. After the first cutting step, a second cutting step of cutting the silicon carbide wafer along a plane substantially perpendicular to the {11-20} plane and substantially perpendicular to the first main surface is performed.

Method of manufacturing silicon carbide semiconductor device

There are prepared a semiconductor substrate having a first main surface and a second main surface, and an adhesive tape having a third main surface and a fourth main surface, the first main surface having a maximum diameter of not less than 100 mm. The semiconductor substrate fixed to the third main surface of the adhesive tape is placed in an accommodation chamber. The accommodation chamber is evacuated while maintaining a temperature of the adhesive tape at not less than 100&#xb0; C. An electrode is formed on the second main surface after the step of reducing the temperature of the semiconductor substrate. The step of evacuating the accommodation chamber includes a step of evacuating the accommodation chamber while maintaining the temperature of the adhesive tape at not less than 100&#xb0; C. with a space being provided between the fourth main surface of the adhesive tape and the substrate holding unit.

Method for manufacturing semiconductor device

A method for manufacturing a semiconductor device includes the following steps. A semiconductor substrate is prepared which has a first main surface and a second main surface opposite to each other. The semiconductor substrate is fixed on an adhesive tape at the first main surface. The semiconductor substrate fixed on the adhesive tape is placed in an accommodating chamber. While maintaining a temperature of the adhesive tape at 100&#xb0; C. or more, a gas is exhausted from the accommodating chamber. After the step of exhausting the gas from the accommodating chamber, a temperature of the semiconductor substrate is reduced. After the step of reducing the temperature of the semiconductor substrate, an electrode is formed on a second main surface of the semiconductor substrate. In this way, there can be provided a method for manufacturing a semiconductor device so as to achieve reduced contact resistance between a semiconductor substrate and an electrode.

In a state where a silicon carbide substrate having a first main surface and second main surface opposite to each other is fixed to a base material having a higher flexibility than the silicon carbide substrate, silicon carbide on a side of second main surface of silicon carbide substrate is removed, and an electrode is formed on the second main surface. The base material has an area which is smaller than or equal to an area of the first main surface of the silicon carbide substrate. In the step of fixing silicon carbide substrate to the base material, the base material is arranged at a position of covering a center of the first main surface so that the base material does not extend beyond an outer circumference of the first main surface.

Method for manufacturing silicon carbide semiconductor device

A method of manufacturing a silicon carbide semiconductor device includes the steps of preparing a silicon carbide substrate, forming a first electrode on the silicon carbide substrate, establishing ohmic contact between the silicon carbide substrate and the first electrode by irradiating the first electrode with laser beams, and forming a second electrode on the first electrode. In the step of establishing ohmic contact, a surface of the first electrode is irradiated with laser beams such that arithmetic mean roughness of a surface of the second electrode is not greater than 0.2 &#x3bc;m.

A silicon carbide substrate having a first main surface and a second main surface opposite to the first main surface is prepared. A surface electrode is formed in contact with the first main surface of the silicon carbide substrate. An adhesive tape is adhered to the surface electrode so as to cover the surface electrode. The silicon carbide substrate is heated at a first pressure lower than atmospheric pressure, with the adhesive tape being adhered to the surface electrode. After the silicon carbide substrate is heated, the second main surface of the silicon carbide substrate is ground. After the second main surface is ground, the second main surface of the silicon carbide substrate is processed at a second pressure lower than atmospheric pressure, with the adhesive tape being adhered to the surface electrode.

A silicon carbide semiconductor device includes: a silicon carbide semiconductor layer; and an electrode layer in contact with the silicon carbide semiconductor layer. In a case where the electrode layer is equally divided into two in a thickness direction in one cross section of the electrode layer in the thickness direction to obtain a first region facing the silicon carbide semiconductor layer and a second region opposite to the silicon carbide semiconductor layer, an area of a carbon portion containing the carbon in the first region is wider than an area of the carbon portion in the second region. At an interface region located up to 300 nm from an interface between the silicon carbide semiconductor layer and the electrode layer, the carbon portion includes a plurality of portions disposed with a space interposed therebetween, and a ratio of area occupied by the carbon portion is not more than 40%.

Silicon carbide semiconductor device

A method for manufacturing a MOSFET includes the steps of: preparing a substrate made of silicon carbide; forming a drain electrode making ohmic contact with the substrate; and forming a backside pad electrode on and in contact with the drain electrode. The drain electrode formed in the step of forming the drain electrode is made of an alloy containing Ti and Si. Further, the backside pad electrode formed is maintained at a temperature of 300&#xb0; C. or smaller until completion of the MOSFET. Accordingly, the manufacturing process can be efficient while achieving excellent adhesion between the electrodes.

A method of manufacturing a semiconductor element of good characteristics at a reduced manufacturing cost is provided. The manufacturing method of the semiconductor element includes a GaN-containing semiconductor layer forming step, an electrode layer forming step, a step of forming an Al film on the GaN-containing semiconductor layer, a step of forming a mask layer made of a material of which etching rate is smaller than that of a material of the Al film, a step of forming a ridge portion using the mask layer as a mask, a step of retreating a position of a side wall of the Al film with respect to a position of a side wall of the mask layer, a step of forming, on the side surface of the ridge portion and the top surface of the mask layer, a protective film made of a material of which etching rate is smaller than that of the material forming the Al film, and a step of removing the Al film and thereby removing the mask layer and a portion of the protective film formed on the top surface of the mask layer.

Manufacturing method of a semiconductor element

A light-emitting device is presented which includes a GaN substratean n-type nitride semiconductor substrate layer (n-type AlGaN layer) disposed on a first main surface side of the GaN substratea p-type nitride semiconductor substrate layer (p-type AlGaN layer) disposed further away from the GaN substratecompared to the n-type nitride semiconductor substrate layer; and a light-emitting layer (multi-quantum well (MQW)) positioned between the n-type nitride semiconductor layer and the p-type nitride semiconductor layer. The p-type nitride semiconductor layer side is down-mounted. Also, light is released from a second main surface, which the main surface opposite from the first main surface of the GaN substrateA grooveis formed on the second main surface of the GaN substrateThe inner perimeter surface of the grooveincludes a section (curved surface section) on which surface treatment is performed to smooth the inner perimeter surface.

Light-emitting device

Affords a semiconductor light-emitting device in which a decrease in external quantum efficiency has been minimized even at high current densities. In a semiconductor light-emitting device (), a gallium nitride cladding layer () has a threading dislocation density of 1&#xd7;10cmor less. An active region () has a quantum well structure () consisted of a plurality of well layers () and a plurality of barrier layers (), and the quantum well structure () is provided so as to emit light having a peak wavelength within the wavelength range of 420 nm to 490 nm inclusive. The well layers () each include an un-doped InGaN (0&#x3c;X&#x3c;0.14, X: strained composition) region. The barrier layers () include an un-doped InGaN (0&#x2266;Y&#x2266;0.05, Y: strained composition, Y&#x3c;X) region. Herein, indium composition X is indicated as strained composition, not as relaxation composition, in the embodiments of the present invention.

Semiconductor light-emitting device and method of manufacturing semiconductor light-emitting device

A light-emitting device is equipped with a GaN substrate; an n-type AlGaN layer on a first main surface side of the GaN substrate; a p-type AlGaN layer positioned further away from the GaN substrate than the n-type AlGaN layer; and a multi-quantum well (MQW) positioned between the n-type AlGaN layer and the p-type AlGaN layer. In the light-emitting device, the p-type AlGaN layer side is down-mounted and light is emitted from a second main surface, which is the main surface opposite from the first main surface of the GaN substrate. The second main surface of the GaN substrate includes a region on which cavities and projections are formed. Also, the light-emitting device includes an n-electrode formed on the second main surface of the GaN substrateand a protective film formed to cover the side wall of the n-electrode.

A light emitting device having a simple structure that can be easily manufactured, attaining high light emitting efficiency stably for a long time is obtained, which light emitting device includes: a GaN substrate as a nitride semiconductor substrate and, on a first main surface of the nitride semiconductor substrate, an n-type AlGaN layer, a p-type AlGaN layer positioned further than the n-type AlGaN layer viewed from the nitride semiconductor substrate, and a quantum well positioned between the n-type AlGaN layer and the p-type AlGaN layer. In the light emitting device, specific resistance of the nitride semiconductor substrate is at most 0.5 &#x3a9;&#xb7;cm, the side of p-type AlGaN layer is mounted face-down, and the light is emitted from the second main surfacethat is opposite to the first main surface of the nitride semiconductor substrate. The second main surfaceof nitride semiconductor substrate has trenches formed therein.

Light emitting device

A light-emitting device includes a GaN substrate; a n-type AlGaN layer on a first main surface side of the GaN substrate; a p-type AlGaN layer positioned further away from the GaN substrate compared to the n-type AlGaN layer; a multi-quantum well (MQW) positioned between the n-type AlGaN layer and the p-type AlGaN layer. In this light-emitting device, the p-type AlGaN layer side is down-mounted and light is emitted from the second main surface, which is the main surface of the GaN substrate opposite from the first main surface. hemispherical projections are formed on the second main surface of the GaN substrate.

Light emitting device, method for making the same, and nitride semiconductor substrate

Surfaces of diamond crystals are examined by coating the surfaces with thin metal films, launching laser beams to the diamond surfaces in a slanting angle, detecting defects and particles on the diamond surfaces by the scattering of beams and counting the defects and particles by a laser scanning surface defect detection apparatus. Diamond SAW devices should be made on the diamond films or bulks with the defect density less than 300 particles cm . Preferably, the diamond,surfaces should have roughness less than Ra20 nm. Diamond SAW filters can be produced by depositing a piezoelectric film and making interdigital transducers on the low-defect density diamond crystals.

Growing community of inventors

Osaka, Japan

Hiroyuki Kitabayashi