Abstract: A disc-like GaN substrate is a substrate produced by a tiling method and having an angel between the normal line and m-axis on the main surface of the substrate of 0 to 20° inclusive and a diameter of 45 to 55 mm, to 4 or less. In a preferred embodiment, a disc-like GaN substrate has a first main surface and a second main surface that is opposite to the first main surface, and which has an angle between the normal line and m-axis on the first main surface of 0 to 20° inclusive and a diameter of 45 mm or more. The disc-like GaN substrate comprises at least four crystalline regions each being exposed to both of the first main surface and the second main surface, wherein the four crystalline regions are arranged in line along the direction of the orthogonal projection of c-axis on the first main surface.

Abstract: A disc-like GaN substrate is a substrate produced by a tiling method and having an angel between the normal line and m-axis on the main surface of the substrate of 0 to 20° inclusive and a diameter of 45 to 55 mm, to 4 or less. In a preferred embodiment, a disc-like GaN substrate has a first main surface and a second main surface that is opposite to the first main surface, and which has an angle between the normal line and m-axis on the first main surface of 0 to 20° inclusive and a diameter of 45 mm or more. The disc-like GaN substrate comprises at least four crystalline regions each being exposed to both of the first main surface and the second main surface, wherein the four crystalline regions are arranged in line along the direction of the orthogonal projection of c-axis on the first main surface.

Abstract: A disc-like GaN substrate is a substrate produced by a tiling method and having an angel between the normal line and m-axis on the main surface of the substrate of 0 to 20° inclusive and a diameter of 45 to 55 mm, to 4 or less. In a preferred embodiment, a disc-like GaN substrate has a first main surface and a second main surface that is opposite to the first main surface, and which has an angle between the normal line and m-axis on the first main surface of 0 to 20° inclusive and a diameter of 45 mm or more. The disc-like GaN substrate comprises at least four crystalline regions each being exposed to both of the first main surface and the second main surface, wherein the four crystalline regions are arranged in line along the direction of the orthogonal projection of c-axis on the first main surface.

Abstract: A disc-like GaN substrate is a substrate produced by a tiling method and having an angel between the normal line and m-axis on the main surface of the substrate of 0 to 20° inclusive and a diameter of 45 to 55 mm, to 4 or less. In a preferred embodiment, a disc-like GaN substrate has a first main surface and a second main surface that is opposite to the first main surface, and which has an angle between the normal line and m-axis on the first main surface of 0 to 20° inclusive and a diameter of 45 mm or more. The disc-like GaN substrate comprises at least four crystalline regions each being exposed to both of the first main surface and the second main surface, wherein the four crystalline regions are arranged in line along the direction of the orthogonal projection of c-axis on the first main surface.

Abstract: Disclosed is a semiconductor etching method whereby a semiconductor layer made of, for example, a Group III-V nitride semiconductor resistant to etching can be etched by a relatively easier process. This etching method comprises forming a metal-fluoride layer 3 at least as a part of an etching mask on the surface of a base structure (1,2); treating the metal-fluoride layer with a liquid; and etching the base structure using the metal-fluoride layer as a mask.

Abstract: A system and method for isothermally distributing a temperature across a semiconductor device. A furnace assembly is provided, which includes a processing tube configured to removably receive a wafer carrier having a full compliment of semiconductor wafers. A heating assembly is provided which can include a heating element positioned to heat air or other gases allowed to enter the process tube. The furnace assembly and process tube are capable of being vertically raised and lowered into a position enclosing the heating assembly within the process tube. Once the heating assembly forms a seal with the process tube, the process tube is exhausted and purged of air. Gas is then allowed to flow into the process tube and exchange heat with the heating element. The heated gas circulates through the process tube to convectively change the temperature of the wafers.

Abstract: A system and method for isothermally distributing a temperature across a semiconductor device. A furnace assembly is provided, which includes a processing tube configured to removably receive a wafer carrier having a full compliment of semiconductor wafers. A heating assembly is provided which can include a heating element positioned to heat air or other gases allowed to enter the process tube. The furnace assembly and process tube are capable of being vertically raised and lowered into a position enclosing the heating assembly within the process tube. Once the heating assembly forms a seal with the process tube, the process tube is exhausted and purged of air. Gas is then allowed to flow into the process tube and exchange heat with the heating element. The heated gas circulates through the process tube to convectively change the temperature of the wafers.

Abstract: A cable modem with a function of packetizing voice information and transmitting/receiving the packetized voice information includes an interface for connection to an ISDN (Integrated Services Digital Network) telephone, a connection control unit which executes a connection control for the ISDN telephone connected via the interface, and a VoIP control unit which executes a VoIP-related protocol process for a voice call by the ISDN telephone that is connection-controlled by the connection control unit.

Abstract: A method for forming a thin film of a silicon oxide on a silicon substrate is disclosed. An Si oxide film is formed by an ECR plasma. CVD with the use of a silicon compound gas containing fluorine, whereby the generation of particles can be suppressed to improve the quality of the device and the yield, the planarity of the Si oxide film functioning as an interlayer dielectric film or a passivation film can be improved, and the higher speed operation in a semiconductor device can be accomplished.