Abstract: A multi-mode interferometric optical waveguide device includes: a multi-mode interferometric optical waveguide which includes a first reflective surface; a first single-mode waveguide connected to the multi-mode interferometric optical waveguide; and a second single-mode waveguide connected to the multi-mode interferometric optical waveguide and oppose the first reflective surface. Consequently, the multi-mode interferometric optical waveguide device can propagate light from the first single-mode waveguide to the second single-mode waveguide, with further reduced optical losses.

Abstract: A film forming apparatus according to an embodiment of the invention includes: a film forming chamber configured to form a film on a substrate; a susceptor configured to place the substrate thereon; a rotating part configured to rotate the susceptor; a heater configured to heat the substrate; and a gas supplier configured to supply process gases into the film forming chamber, wherein the susceptor includes: a ring-shaped outer circumferential susceptor supported by the rotating part; a holder provided at an inner circumferential portion of the outer circumferential susceptor, the holder configured to hold the substrate; a ring-shaped plate provided over the outer circumferential susceptor; and a cover member configured to cover a top surface and an outer circumferential surface of the plate and an outer circumferential surface of the outer circumferential susceptor.

Abstract: In a silicon carbide semiconductor film forming apparatus, first to third gasses are introduced into first to third separation chambers through first to third inlets, respectively. The first and second gasses are silicon raw material including gas and carbon raw material including gas, and the third gas does not include silicon and carbon. The first and second gasses are independently supplied to growth space through first and second supply paths extending from the first and second separation chambers, respectively. The third gas is introduced through a third supply path from the third separation chamber between the first and second gasses.

Abstract: It is an object of the present invention to provide a film-forming apparatus and a film-forming method that can prolong the lifetime of heaters used under high temperature conditions in an epitaxial growth technique. An inert gas discharge portion supplies an inert gas into the space containing the heater, gas is then discharged through the gas discharge portion without influence on the semiconductor substrate during film formation. It is therefore possible to prevent the reaction gas entering into the space containing the high-temperature heaters. This makes it possible to prevent a reaction between hydrogen gas contained in the reaction gas and SiC constituting the heaters. Therefore, it is possible to prevent carbon used as a base material of the heaters from being exposed due to the decomposition of SiC and then reacting with hydrogen gas. This makes it possible to prolong the lifetime of the heaters.

Abstract: A film-forming apparatus and method comprising a film-forming chamber for supplying a reaction gas into, a cylindrical shaped liner provided between an inner wall of the film-forming chamber and a space for performing a film-forming process, a main-heater for heating a substrate placed inside the liner, from the bottom side, a sub-heater cluster provided between the liner and the inner wall, for heating the substrate from the top side, wherein the main-heater and the sub-heater cluster are resistive heaters, wherein the sub-heater cluster has a first sub-heater provided at the closest position to the substrate, and a second sub-heater provided above the first sub-heater, wherein the first sub-heater heats the substrate in combination with the main-heater, the second sub-heater heats the liner at a lower output than the first sub-heater, wherein each temperature of the main-heater, the first sub-heater, and the second sub-heater is individually controlled.

Abstract: At the time of transporting a substrate into or from a space where a film formation process is performed, the space where the film formation process is performed, a space where a lower heater 16 is provided, and a space where an upper heater 19 is provided are made in an inert gas atmosphere.

Abstract: A film formation apparatus according to an embodiment includes: a film formation chamber performing film formation on a substrate; a cylindrical liner provided inside of a sidewall of the film formation chamber; a process-gas supply unit provided at a top of the film formation chamber and having a first gas ejection hole supplying a process gas to inside of the liner; a first heater provided outside the liner in the film formation chamber and heating the substrate from above; a second heater heating the substrate from below; and a shielding gas supply unit having a plurality of second gas ejection holes supplying a shielding gas to a position closer to a sidewall of the film formation chamber than a position of the first gas ejection hole.

Abstract: A semiconductor device is provided with a silicon layer, an upper surface side aluminum layer containing silicon and an insulation film. The upper surface side aluminum layer contacts and is layered on a part of a surface of the silicon layer. The insulation film contacts and is layered on another part of the surface of the silicon layer. The insulation film is adjacent to and contacts the upper surface side aluminum layer. The insulation film includes an insulation film body and a plurality of first nodule segregated portions projecting from the insulation film body toward the upper surface side aluminum layer as seen along a vertical direction relative to the surface of the silicon layer. A corner is formed by a side surface of the insulation film body and a side surface of each of the first nodule segregated portions as seen along the vertical direction.

Abstract: In a silicon carbide semiconductor film forming apparatus, first to third gasses are introduced into first to third separation chambers through first to third inlets, respectively. The first and second gasses are silicon raw material including gas and carbon raw material including gas, and the third gas does not include silicon and carbon. The first and second gasses are independently supplied to growth space through first and second supply paths extending from the first and second separation chambers, respectively. The third gas is introduced through a third supply path from the third separation chamber between the first and second gasses.

Abstract: A film-forming apparatus and method comprising a film-forming chamber for supplying a reaction gas into, a cylindrical shaped liner provided between an inner wall of the film-forming chamber and a space for performing a film-forming process, a main-heater for heating a substrate placed inside the liner, from the bottom side, a sub-heater cluster provided between the liner and the inner wall, for heating the substrate from the top side, wherein the main-heater and the sub-heater cluster are resistive heaters, wherein the sub-heater cluster has a first sub-heater provided at the closest position to the substrate, and a second sub-heater provided above the first sub-heater, wherein the first sub-heater heats the substrate in combination with the main-heater, the second sub-heater heats the liner at a lower output than the first sub-heater, wherein each temperature of the main-heater, the first sub-heater, and the second sub-heater is individually controlled.

Abstract: A film forming apparatus according to an embodiment of the invention includes: a film forming chamber configured to form a film on a substrate; a susceptor configured to place the substrate thereon; a rotating part configured to rotate the susceptor; a heater configured to heat the substrate; and a gas supplier configured to supply process gases into the film forming chamber, wherein the susceptor includes: a ring-shaped outer circumferential susceptor supported by the rotating part; a holder provided at an inner circumferential portion of the outer circumferential susceptor, the holder configured to hold the substrate; a ring-shaped plate provided over the outer circumferential susceptor; and a cover member configured to cover a top surface and an outer circumferential surface of the plate and an outer circumferential surface of the outer circumferential susceptor.

Abstract: An SBD is obtained by forming, on a front surface of a substrate in which a first nitride semiconductor layer and a second nitride semiconductor layer are laminated, an anode electrode configured to make Schottky contact and a cathode electrode configured to make Ohmic contact. The anode electrode is made to have a mixture of a portion that is in direct contact with the second nitride semiconductor layer and a portion that is in contact with the second nitride semiconductor layer via a fourth nitride semiconductor layer and a third nitride semiconductor layer. Using a p-type nitride semiconductor as the fourth layer makes it possible to suppress the leakage current. Using, as the third layer, a nitride semiconductor that is wider in band gap than the second nitride semiconductor layer makes it possible to keep down the lowest value of forward voltage at which a forward current flows.

Abstract: It is an object of the present invention to provide a film-forming apparatus and a film-forming method that can prolong the lifetime of heaters used under high temperature conditions in an epitaxial growth technique. An inert gas discharge portion supplies an inert gas into the space containing the heater, gas is then discharged through the gas discharge portion without influence on the semiconductor substrate during film formation. It is therefore possible to prevent the reaction gas entering into the space containing the high-temperature heaters. This makes it possible to prevent a reaction between hydrogen gas contained in the reaction gas and SiC constituting the heaters. Therefore, it is possible to prevent carbon used as a base material of the heaters from being exposed due to the decomposition of SiC and then reacting with hydrogen gas. This makes it possible to prolong the lifetime of the heaters.

Abstract: A susceptor processing method according to an embodiment includes: placing a plate on a susceptor arranged in a film forming chamber; heating the susceptor in order to have a temperature higher than that of the plate by using a main heater arranged below the susceptor and an auxiliary heater arranged in an upper part of the film forming chamber, and subliming a SIC film having been formed on a surface of the susceptor and adhering the sublimed SIC on the plate; and transporting the plate from the film forming chamber, the plate having SIC adhered thereon.

Abstract: A semiconductor device is provided with a silicon layer, an upper surface side aluminum layer containing silicon and an insulation film. The upper surface side aluminum layer contacts and is layered on a part of a surface of the silicon layer. The insulation film contacts and is layered on another part of the surface of the silicon layer. The insulation film is adjacent to and contacts the upper surface side aluminum layer. The insulation film includes an insulation film body and a plurality of first nodule segregated portions projecting from the insulation film body toward the upper surface side aluminum layer as seen along a vertical direction relative to the surface of the silicon layer. A corner is formed by a side surface of the insulation film body and a side surface of each of the first nodule segregated portions as seen along the vertical direction.

Abstract: A silicon carbide single crystal includes nitrogen as a dopant and aluminum as a dopant. A nitrogen concentration is 2×1019 cm?3 or higher and a ratio of an aluminum concentration to the nitrogen concentration is within a range of 5% to 40%.

Abstract: A film formation apparatus according to an embodiment includes: a film formation chamber performing film formation on a substrate; a cylindrical liner provided inside of a sidewall of the film formation chamber; a process-gas supply unit provided at a top of the film formation chamber and having a first gas ejection hole supplying a process gas to inside of the liner; a first heater provided outside the liner in the film formation chamber and heating the substrate from above; a second heater heating the substrate from below; and a shielding gas supply unit having a plurality of second gas ejection holes supplying a shielding gas to a position closer to a sidewall of the film formation chamber than a position of the first gas ejection hole.

Abstract: At the time of transporting a substrate into or from a space where a film formation process is performed, the space where the film formation process is performed, a space where a lower heater 16 is provided, and a space where an upper heater 19 is provided are made in an inert gas atmosphere.

Abstract: The network relay device is provided. The network relay device includes: a plurality of ports, each being configured to be connectable with one physical line; a virtual line controller configured to treat a plurality of physical lines, which are respectively connected with the plurality of ports, to constitute a virtual line; and a status check frame controller configured to send via the virtual line a status check frame for use in checking status of a network, which the network relay device is connected with via the virtual line, wherein the status check frame controller changes a frame-sending port to be used to send a next status check frame, in order to avoid continuously using an identical port as both a frame-sending port to send the status check frame and a frame-receiving port to receive the status check frame from another network relay device.

Abstract: A method of manufacturing a semiconductor device, includes increasing adherence between a susceptor as a heating element, and a semiconductor substrate disposed on the susceptor, by using an adherence increasing mechanism, or increasing heat transmitted to a semiconductor substrate, which is disposed on a susceptor as a heating element, by using a transmitted-heat increasing mechanism; and heating the semiconductor substrate to have a predetermined temperature by heating the susceptor. The adherence increasing mechanism may include the susceptor and one of a heavy-weight stone disposed on the semiconductor substrate, a cap disposed on the semiconductor substrate and engaged with the susceptor, and an adhesive layer provided between the susceptor and the semiconductor substrate. The transmitted-heat increasing mechanism may include the susceptor and small pieces which are disposed on the semiconductor substrate and have radiated-light absorption ability.