Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Toshihiko Shiga

Hitoshi Sakuma

Kazushige Kawasaki

Katsuomi Shiozawa

Toshiyuki Oishi

Tomoki Oku

Koichiro Nishizawa

Hitoshi Nakamura

Junichi Horie

Ryo Hattori

Yoshitsugu Yamamoto

Shinsuke Watanabe

Kazuhiro Maeda

Katsumi Miyawaki

Yasuyuki Nakagawa

Shinichi Miyakuni

Yoshitaka Kamo

Takayuki Hisaka

Naohito Yoshida

Kyozo Kanamoto

Hidetoshi Koyama

Junji Tanimura

Takahiro Nakamoto

Hiromasu Matsuoka

Takeo Shirahama

Kouichirou Hori

A semiconductor device according to the present invention includes: a substrate; a heat generating portion provided on the substrate; a cap substrate provided above the substrate so that a hollow portion is provided between the substrate and the cap substrate; and a reflection film provided above the heat generating portion and reflecting a medium wavelength infrared ray. The reflection film reflects the infrared ray radiated to the cap substrate side through the hollow portion due to the temperature increase of the heat generating portion, so that the temperature increase of the cap substrate side can be suppressed. Because of this function, even if mold resin is provided on the cap substrate, increase of the temperature of the mold resin can be suppressed.

Semiconductor device

A semiconductor device includes a substrate having a hexagonal crystalline structure and a (0001) surface, and conductive films on the surface of the substrate. The conductive films include a first conductive film and a second conductive film located above the first conductive film with respect to the surface, wherein the first conductive film has a crystalline structure which does not have a plane that has a symmetry equivalent to the symmetry of atomic arrangement in the surface of the substrate, the second conductive film has a crystalline structure having at least one plane that has a symmetry equivalent to the symmetry of atomic arrangement in the surface of the substrate, and the second conductive film is polycrystalline and has a grain size no larger than 15 &#x3bc;m.

Semiconductor device and method of manufacturing semiconductor device

A semiconductor device includes: a semiconductor substrate; an underlying wiring on the semiconductor substrate; a resin film extending to the semiconductor substrate and the underlying wiring, and having a first opening on the underlying wiring; a first SiN film on the underlying wiring and the resin film, and having a second opening in the first opening; an upper layer wiring on the underlying wiring and part of the resin film; and a second SiN film on the upper layer wiring and the resin film, and joined to the first SiN film on the resin film. The upper layer wiring includes a Ti film, connected to the underlying wiring via the first and second openings, and an Au film on the Ti film. The first and second SiN films circumferentially protect the Ti film.

A method for manufacturing a laser diode includes: providing a semiconductor structure in which semiconductor layers are laminated; forming a waveguide ridge in the layers; forming an SiOfilm over the entire surface; forming a second resist pattern covering the SiOfilm in channels adjacent the waveguide ridge such that top surfaces of the second resist pattern in the channels are higher than the top surface of a p-GaN layer in the waveguide ridge and lower than the top surface of the SiOfilm on the top of the waveguide ridge, the second resist pattern exposing the top surface of the SiOfilm on the top of the waveguide ridge; removing the SiOfilm, using the second resist pattern as a mask, to expose the top surface of the p-GaN layer in the waveguide ridge; and forming an electrode layer on the top surface of the p-GaN layer.

Method for manufacturing semiconductor optical device

A transistor includes a nitride semiconductor layer and a gate electrode layer. The gate electrode layer includes a tantalum nitride layer on the nitride semiconductor layer. The tantalum nitride layer forms a Schottky junction with the nitride semiconductor layer. The transistor also includes an insulating film on the nitride semiconductor layer. The insulating film surrounds the gate electrode layer. A first portion of the gate electrode layer, in contact with the nitride semiconductor layer, has a higher nitrogen mole fraction than a second portion of the gate electrode layer.

Transistor

A nitride semiconductor device includes an n-type GaN substrate with a semiconductor device formed thereon and an n-type electrode which is a metal electrode formed on the rear surface of the GaN substrate. A surface modified layer and a reaction layer are interposed between the GaN substrate and n-type electrode. The surface modified layer serves as a carrier supplying layer, and is formed by causing the rear surface of the GaN substrate to react with a Si-containing plasma to be modified. The reaction layer is generated by partially removing a deposited material deposited on the surface modified layer by cleaning to generate a deposited layer and then causing Ti contained in a first metal layer and the deposited layer to partially react by heat treatment.

Nitride semiconductor device and manufacturing method of the same

A nitride semiconductor device according to the present invention includes a P-type contact layer and a P-type electrode provided on the P-type contact layer. The P-type electrode includes a AuGa film provided on the P-type contact layer, a Au film provided on the AuGa film, a Pt filmprovided on the Au film, and a Au film provided on the Pt film. The ratio of the thickness of the AuGa film to the total thickness of the AuGa film and the Au film is not less than 12% but not more than 46%.

Nitride semiconductor device and method of manufacturing the same

A semiconductor laser device includes a semiconductor laser body including a resonator and having a front end face and a rear end face facing each other, the resonator being located between the front end face and the rear end face. The front end face emits principal laser light. A reflectance control film is disposed on the front end face or the rear end face of the semiconductor laser body and is made up of either an aluminum oxide film or a five-layer film including the aluminum oxide film disposed such that it is the layer in the five-layer film farthest from the front end face or the rear end face. A silicon oxide film is disposed on the aluminum oxide film of the reflectance control film and has a thickness of 20 nm or less.

Semiconductor laser device

A Schottky electrode including a WNx layer on an n-type GaN layer. A crystal plane of the n-type GaN layer is in contact with a crystal plane of the WNx layer. The crystal plane of the n-type GaN layer is a (0001)-plane, and the crystal plane of the WNx layer is (111)-oriented. The WNx layer may be an electrode layer having an NaCl-type structure including at least one metal selected from the group consisting of zirconium, hafnium, niobium, tantalum, molybdenum and tungsten, and at least one element selected from nitrogen and carbon. Further, the lattice constant of the electrode layer is preferably 0.95 to 1.05 times the a-axis lattice constant of the n-type GaN layer, multiplied by 2.

Semiconductor device and field-effect transistor

An ohmic electrode is formed by stacking a lower Ti layer, a diffusion preventing layer, an upper Ti layers and a metallic (Au) layer on a p-type GaAs layer. The diffusion preventing layer includes tantalum (Ta) or niobium (Nb). Thus, interdiffusion of Ga and As in the p-type GaAs layer and Au in the metallic layer can be prevented, and variation in resistivity of the ohmic electrode in a high-temperature, high-humidity environment can be suppressed.

Semiconductor device having an improved wiring or electrode structure

In a method for manufacturing a semiconductor device wherein via holes are formed in an SiC substrate, a stacked film consisting of a Ti film and an Au film is formed on the back face of the SiC substrate, and a Pd film is formed thereon. Then, an Ni film is formed by non-electrolytic plating, using the Pd film as a catalyst. Thereafter, via holes penetrating through the SiC substrate are formed by etching, using the Ni film as a mask.

Method for manufacturing semiconductor device having via holes

A semiconductor device includes a self-aligned refractory metal constituent in a recess in a semiconductor substrate and having the same plane pattern as a bottom surface of the recess. The width of the constituent is determined by the plane pattern of the recess and, accordingly, the pattern width of the constituent is easily controlled by the plane pattern of the recess.

Semiconductor device with refractory metal element

A semiconductor device includes a semiconductor substrate having a surface; an active layer of a compound semiconductor disposed at the surface of the semiconductor substrate; and a Schottky barrier gate electrode including a multi-layer film alternately laminating a conductive refractory metal compound layer including a first refractory metal (M.sub.1) and a second refractory metal (M.sub.2) layer to three or more layers respectively, disposed on the active layer, thereby forming a Schottky junction with the active layer. The gate resistance of the Schottky barrier gate electrode can be held low and the internal stress can be reduced, whereby peeling off of the can be suppressed.

Semiconductor device with laminated refractory metal schottky barrier

A method for manufacturing a semiconductor device including forming an electrode on a part of a semiconductor substrate, depositing an insulating film on the semiconductor substrate and on the electrode, and forming a contact hole penetrating through the insulating film to expose a part of the electrode; forming a barrier metal layer on the electrode in the contact hole, on the internal side surface of the contact hole, and on the surface of the insulating film; and depositing a metal layer on the barrier metal layer and patterning the metal layer and the barrier metal layer to form a wiring layer wherein the barrier metal layer comprises a metal that does not form an intermetallic material by solid state diffusion with either of the electrode and the metal layer even at elevated temperatures.

Growing community of inventors

Tokyo, Japan

Toshihiko Shiga