Abstract: Provided is a semiconductor manufacturing apparatus that is capable of, while holding one surface of the wafer, grinding the holding surface of a wafer. A semiconductor manufacturing apparatus includes a first main surface holding unit that comes into contact with a center portion of a first main surface of a wafer in plan view and holds the wafer, and a first grinding unit that rotates about a rotation axis that overlaps a center of the wafer in plan view and extends in a direction perpendicular to the first main surface, and that grinds an outer periphery that is a region surrounding the center portion of the first main surface in contact with the outer periphery of the first main surface.

Abstract: A semiconductor inspection apparatus includes a defect detection unit and a control unit. The defect detection unit inspects a first main surface of a semiconductor wafer including an SiC crystal having the first main surface and a second main surface and inclined at an off angle in a predetermined direction to detect a first defect which is a crystal defect included in the first main surface, and inspects the second main surface to detect a second defect which is a crystal defect included in the second main surface. The control unit controls the defect detection unit to inspect an inspection region that is a partial region of the second main surface of the semiconductor wafer when the defect detection unit detects the second defect. The inspection region is determined based on the detected position of the first defect, and the thickness and the off angle of the semiconductor wafer.

Abstract: The object of the present invention is to enhance the device yield of SiC epitaxial wafers. The SiC epitaxial wafer includes a drift layer which is a SiC epitaxial layer. The drift layer has a film thickness of 18 ?m or more and 350 ?m or less and has arithmetic average roughness of 0.60 nm or more and 3.00 nm or less, and the impurity concentration thereof is 1×1014/cm3 or more and 5×1015/cm3 or less.

Abstract: A SiC substrate (1) has an off angle ?°. A SiC epitaxial layer (2) having a film thickness of Tm ?m is provided on the SiC substrate (1). Triangular defects (3) are formed on a surface of the SiC epitaxial layer (2). A density of triangular defects (3) having a length of Tm/Tan ?×0.9 or more in a substrate off direction is denoted by A. A density of triangular (3) defects having a length smaller than Tm/Tan ?×0.9 in the substrate off direction is denoted by B. B/A?0.5 is satisfied.

Abstract: A SiC substrate (1) has an off angle ?°. A SiC epitaxial layer (2) having a film thickness of Tm ?m is provided on the SiC substrate (1). Triangular defects (3) are formed on a surface of the SiC epitaxial layer (2). A density of triangular defects (3) having a length of Tm/Tan ?×0.9 or more in a substrate off direction is denoted by A. A density of triangular (3) defects having a length smaller than Tm/Tan ?×0.9 in the substrate off direction is denoted by B. B/A?0.5 is satisfied.

Abstract: An epitaxial substrate includes a single-crystal substrate of silicon carbide, and an epitaxial layer of silicon carbide disposed on the single-crystal substrate. The epitaxial layer includes a first epitaxial layer disposed on the single-crystal substrate, a second epitaxial layer disposed on the first epitaxial layer, and a third epitaxial layer disposed on the second epitaxial layer. The first epitaxial layer has a basal-plane-dislocation conversion rate of less than 95%. The second epitaxial layer has a basal-plane-dislocation conversion rate of more than 98%.

Abstract: [Object] To efficiently supply lubricant oil to a bearing member with a simple mechanism. [Solving Means] A vacuum pump includes a first housing, a second housing, a rotor shaft, a lubricant oil-stirring plate, and a bearing member. The second housing is attached to the first housing and forms a space that stores lubricant oil together with the first housing. The rotor shaft passes through the first housing. The lubricant oil-stirring plate is housed in the space and is attached to the rotor shaft. The bearing member is fixed to the first housing and rotatably supports the rotor shaft. The first housing includes a supply port that enables lubricant oil to be supplied to the bearing member. The second housing includes an inner-wall upper portion which the lubricant oil stirred by the lubricant oil-stirring plate hits against. The inner-wall upper portion of the second housing includes a recess portion that enables the lubricant oil to move above the supply port.

Abstract: A vacuum pump according to an embodiment of the present invention includes a pump main body, a first temperature sensor, a motor, and a control unit. The pump main body includes a rotary shaft and a metal casing portion. The first temperature sensor is attached to the casing portion and detects a temperature of the casing portion. The motor includes a rotor core including a permanent magnet and attached to the rotary shaft, a stator core including a plurality of coils, and a can that houses the rotor core. The control unit includes a driving circuit and a correcting circuit. The driving circuit supplies the plurality of coils with a driving signal for rotating the motor on a basis of a pre-set induced voltage constant. The correcting circuit corrects the induced voltage constant on a basis of an output of the first temperature sensor.

Abstract: [Object] To efficiently supply lubricant oil to a bearing member with a simple mechanism. [Solving Means] A vacuum pump includes a first housing, a second housing, a rotor shaft, a lubricant oil-stirring plate, and a bearing member. The second housing is attached to the first housing and forms a space that stores lubricant oil together with the first housing. The rotor shaft passes through the first housing. The lubricant oil-stirring plate is housed in the space and is attached to the rotor shaft. The bearing member is fixed to the first housing and rotatably supports the rotor shaft. The first housing includes a supply port that enables lubricant oil to be supplied to the bearing member. The second housing includes an inner-wall upper portion which the lubricant oil stirred by the lubricant oil-stirring plate hits against. The inner-wall upper portion of the second housing includes a recess portion that enables the lubricant oil to move above the supply port.

Abstract: A semiconductor wafer includes a silicon carbide substrate having a first carrier concentration, a carrier concentration transition layer, and an epitaxial layer provided on the carrier concentration transition layer, the epitaxial layer having a second carrier concentration, and the second carrier concentration being lower than the first carrier concentration. The carrier concentration transition layer has a concentration gradient in the thickness direction. The carrier concentration decreases as the film thickness increases from an interface between a layer directly below the carrier concentration transition layer and the carrier concentration transition layer, and the carrier concentration decreases at a lower rate of decrease as the film thickness of the carrier concentration transition layer increases.

Abstract: A semiconductor wafer includes a silicon carbide substrate having a first carrier concentration, a carrier concentration transition layer, and an epitaxial layer provided on the carrier concentration transition layer, the epitaxial layer having a second carrier concentration, and the second carrier concentration being lower than the first carrier concentration. The carrier concentration transition layer has a concentration gradient in the thickness direction. The carrier concentration decreases as the film thickness increases from an interface between a layer directly below the carrier concentration transition layer and the carrier concentration transition layer, and the carrier concentration decreases at a lower rate of decrease as the film thickness of the carrier concentration transition layer increases.

Abstract: The object of the present invention is to enhance the device yield of SiC epitaxial wafers. The SiC epitaxial wafer includes a drift layer which is a SiC epitaxial layer. The drift layer has a film thickness of 18 ?m or more and 350 ?m or less and has arithmetic average roughness of 0.60 nm or more and 3.00 nm or less, and the impurity concentration thereof is 1×1014/cm3 or more and 5×1015/cm3 or less.

Abstract: A method for manufacturing an SiC substrate includes: performing a CMP treatment on an SiC substrate; after the CMP treatment, capturing an image of a surface of the SiC substrate to detect a scratch; determining the SiC substrate as a good article when a length L of the scratch having a contrast value equal to or larger than a threshold value is not more than ?(D/2)2/A×F/100, wherein the scratch having the contrast value equal to or larger than the threshold value in the image serves as a starting point of an epitaxial defect, a diameter of the SiC substrate is represented by D, a length of a long side of a device chip to be formed on the SiC substrate is represented by A, and an allowable defective rate caused by scratches is represented by F.

Abstract: A SiC substrate (1) has an off angle ?°. A SiC epitaxial layer (2) having a film thickness of Tm ?m is provided on the SiC substrate (1). Triangular defects (3) are formed on a surface of the SiC epitaxial layer (2). A density of triangular defects (3) having a length of Tm/Tan ?×0.9 or more in a substrate off direction is denoted by A. A density of triangular (3) defects having a length smaller than Tm/Tan ?×0.9 in the substrate off direction is denoted by B. B/A?0.5 is satisfied.

Abstract: A method for manufacturing an SiC substrate includes: performing a CMP treatment on an SiC substrate; after the CMP treatment, capturing an image of a surface of the SiC substrate to detect a scratch; determining the SiC substrate as a good article when a length L of the scratch having a contrast value equal to or larger than a threshold value is not more than ?(D/2)2/A×F/100, wherein the scratch having the contrast value equal to or larger than the threshold value in the image serves as a starting point of an epitaxial defect, a diameter of the SiC substrate is represented by D, a length of a long side of a device chip to be formed on the SiC substrate is represented by A, and an allowable defective rate caused by scratches is represented by F.

Abstract: An epitaxial substrate includes a single-crystal substrate of silicon carbide, and an epitaxial layer of silicon carbide disposed on the single-crystal substrate. The epitaxial layer includes a first epitaxial layer disposed on the single-crystal substrate, a second epitaxial layer disposed on the first epitaxial layer, and a third epitaxial layer disposed on the second epitaxial layer. The first epitaxial layer has a basal-plane-dislocation conversion rate of less than 95%. The second epitaxial layer has a basal-plane-dislocation conversion rate of more than 98%.

Abstract: A manufacturing method for manufacturing a silicon carbide epitaxial wafer includes: introducing a cleaning gas into a growth furnace to remove dendrite-like polycrystal of silicon carbide attached to an inner wall of the growth furnace; after introducing the cleaning gas, bringing a silicon carbide substrate in the growth furnace; and growing a silicon carbide epitaxial layer on the silicon carbide substrate by introducing a processing gas into the growth furnace to manufacture a silicon carbide epitaxial wafer, wherein the cleaning gas having fluid energy of 1.6E?4 [J] or higher is introduced into the growth furnace.

Abstract: A manufacturing method for manufacturing a silicon carbide epitaxial wafer includes: introducing a cleaning gas into a growth furnace to remove dendrite-like polycrystal of silicon carbide attached to an inner wall of the growth furnace; after introducing the cleaning gas, bringing a silicon carbide substrate in the growth furnace; and growing a silicon carbide epitaxial layer on the silicon carbide substrate by introducing a processing gas into the growth furnace to manufacture a silicon carbide epitaxial wafer, wherein the cleaning gas having fluid energy of 1.6E-4 [J] or higher is introduced into the growth furnace.

Abstract: According to one embodiment, a controller controls writing into and reading from a storage apparatus that includes a first data-storage unit and a second data-storage unit. The second data-storage unit stores user data and parity data of the user data. The first data-storage unit stores the parity data. The controller includes a parity updating unit and a parity writing unit. When parity data is updated, the parity updating unit writes the updated parity data into the first data-storage unit. When a certain requirement is satisfied, the parity writing unit reads the parity data written in the first data-storage unit, and writes the parity data thus read into the second data-storage unit.

Abstract: A plurality of free-block management lists for respectively managing a logical block with a same bank number, a same chip number, and a same plane number as a free block, and a free block selecting unit that selects a required number of free-block management lists from the free-block management lists to obtain a free block from the selected free-block management lists are provided.