Abstract: A crucible for growing a single-crystal in which a raw material melt for growing the single-crystal is solidified while being accommodated includes a side wall part configured to surround the raw material melt and a bottom part configured to support the raw material melt while being continuous with the side wall part, in which the side wall part has circumferential length redundancy inside the side wall part in a cross-sectional view. The side wall part has a portion where the circumference length is redundant inside any portion in the cross-sectional view, and when the crucible for growing a single-crystal is cooled in a cooling process after the single-crystal growth, the portion where the circumference length is redundant inside in the cross-sectional view is expanded to an outside of the crucible for growing a single-crystal.

Abstract: To prevent dielectric breakdown of a Schottky barrier diode using gallium oxide. A Schottky barrier diode has a drift layer provided on a semiconductor substrate, an anode electrode, and a cathode electrode. A width W1 of an outer peripheral trench formed in the drift layer is larger than a width W2 of a center trench. An outer peripheral wall S1 of the outer peripheral trench is curved so as to approach vertical toward the outside, while an inner peripheral wall S2 thereof is closer to vertical than the outer peripheral wall S1. This relaxes an electric field which occurs at the outer peripheral bottom portion of the outer peripheral trench upon application of a backward voltage.

Abstract: A Schottky barrier diode 1 includes: a semiconductor substrate made of gallium oxide; a drift layer made of gallium oxide; an anode electrode brought into Schottky contact with an upper surface of the drift layer; and a cathode electrode brought into ohmic contact with a lower surface of the semiconductor substrate. A ring-shaped outer peripheral trench is formed in the upper surface of the drift layer, and the anode electrode is partly filled in the outer peripheral trench. A ring-shaped back surface trench is formed in the lower surface of the semiconductor substrate such that the bottom thereof reaches the drift layer. This limits a current path to the area surrounded by the back surface trench, thereby mitigating electric field concentration in the vicinity of the bottom of the outer peripheral trench.

Abstract: To prevent dielectric breakdown of a Schottky barrier diode using gallium oxide. A Schottky barrier diode has a drift layer provided on a semiconductor substrate, an anode electrode, and a cathode electrode. A part of the anode electrode is embedded in an outer peripheral trench and a center trench through an insulating film. The insulating film is formed such that the thickness thereof in the depth direction of the outer peripheral trench becomes larger toward the outside, whereby an outer peripheral wall S1 of the anode electrode embedded in the outer peripheral trench is curved so as to approach vertical toward the outside. This results in relaxation of an electric field which occurs at the outer peripheral bottom portion of the outer peripheral trench upon application of a backward voltage.

Abstract: In a crystal manufacturing method, first, a feedstock including a tapered tip portion is disposed above a crystal growth region. Then, a side surface of the tip portion is selectively heated and melted by radiant heat traveling diagonally upward while a shape of the tip portion is maintained, and the side surface of the tip portion is physically connected to an upper surface of the crystal growth region by a material melted from the side surface. In a crystal manufacturing apparatus, the radiant heat for melting the feedstock is radiated from an electric resistance heater.

Abstract: A power supply apparatus includes a transformer including primary and secondary coils, a heatsink that radiates heat, and a substrate supporting the heatsink and including primary and secondary circuits. The transformer outputs a voltage to the secondary coil according to a voltage input to the primary coil. The heatsink includes a protruding portion protruding from a position where the heatsink is in contact with the substrate in a direction protruding from a surface of the substrate. The heatsink further includes an extending portion extending from part of the protruding portion to an area of the secondary circuit of the transformer, in a state spaced apart from the substrate. The extending portion enters the area of the secondary circuit when viewed in a direction perpendicular to the surface of the substrate. A distance between the extending portion and the surface of the substrate is longer than at least 1 millimeter (mm).

Abstract: A Schottky barrier diode includes an anode electrode which is brought into Schottky contact with a drift layer, a cathode electrode which is brought into ohmic contact with a semiconductor substrate, an insulating film covering the inner wall of a trench formed in the drift layer, a metal film covering the inner wall of the trench through the insulating film and electrically connected to the anode electrode, and a field insulating layer. The field insulating layer includes a first part positioned between an upper surface of the drift layer and the anode electrode and a second part covering the inner wall of the trench through the metal film and insulating film. With this configuration, even when misalignment occurs between the trench and the field insulating layer, dielectric breakdown can be prevented.

Abstract: An object of the present invention is to provide a Schottky barrier diode which is less likely to cause dielectric breakdown due to concentration of an electric field. A Schottky barrier diode includes a semiconductor substrate 20 made of gallium oxide, a drift layer 30 made of gallium oxide and provided on the semiconductor substrate 20, an anode electrode 40 brought into Schottky contact with the drift layer 30, and a cathode electrode 50 brought into ohmic contact with the semiconductor substrate 20. The drift layer 30 has an outer peripheral trench 10 formed at a position surrounding the anode electrode 40 in a plan view. An electric field is dispersed by the presence of the outer peripheral trench 10 formed in the drift layer 30. This alleviates concentration of the electric field on the corner of the anode electrode 40, making it unlikely to cause dielectric breakdown.

Abstract: A Schottky barrier diode 1 includes: a semiconductor substrate made of gallium oxide; a drift layer made of gallium oxide; an anode electrode brought into Schottky contact with an upper surface of the drift layer; and a cathode electrode brought into ohmic contact with a lower surface of the semiconductor substrate. A ring-shaped outer peripheral trench is formed in the upper surface of the drift layer, and the anode electrode is partly filled in the outer peripheral trench. A ring-shaped back surface trench is formed in the lower surface of the semiconductor substrate such that the bottom thereof reaches the drift layer. This limits a current path to the area surrounded by the back surface trench, thereby mitigating electric field concentration in the vicinity of the bottom of the outer peripheral trench.

Abstract: A Schottky barrier diode includes a semiconductor substrate made of gallium oxide, a drift layer made of gallium oxide and provided on the semiconductor substrate, an anode electrode brought into Schottky contact with the drift layer, and a cathode electrode brought into ohmic contact with the semiconductor substrate. The drift layer has a plurality of trenches formed in a position overlapping the anode electrode in a plan view. Among the plurality of trenches, a trench positioned at the end portion has a selectively increased width. Thus, the curvature radius of the bottom portion of the trench is increased, or an edge part constituted by the bottom portion as viewed in a cross section is divided into two parts. As a result, an electric field to be applied to the bottom portion of the trench positioned at the end portion is mitigated, making dielectric breakdown less likely to occur.

Abstract: An object of the present invention is to provide a Schottky barrier diode less liable to cause dielectric breakdown due to concentration of an electric field. A Schottky barrier diode according to this disclosure includes a semiconductor substrate made of gallium oxide, a drift layer made of gallium oxide and provided on the semiconductor substrate, an anode electrode 40 brought into Schottky contact with the drift layer, a cathode electrode brought into ohmic contact with the semiconductor substrate, an insulating layer provided on the drift layer so as to surround the anode electrode in a plan view, and a semiconductor layer provided on a surface of a part of the drift layer that is positioned between the anode electrode and the insulating layer and on the insulating layer. The semiconductor layer has a conductivity type opposite to that of the drift layer.

Abstract: A power supply apparatus includes a transformer, an electrolytic capacitor provided in primary circuitry of the transformer, a board, and a heat sink having a protruding portion and a cover portion. The electrolytic capacitor includes an explosion-proof valve that opens to cause an electrolytic solution to be jetted from the electrolytic capacitor. The electrolytic capacitor is placed on the board so that a surface of the electrolytic capacitor opposite to a surface on which the explosion-proof valve is provided faces the board. The cover portion has a hole formed in the cover portion and, when the cover portion is viewed in a direction vertical to the surface of the electrolytic capacitor on which the explosion-proof valve is provided, at least the explosion-proof valve and the hole formed in the cover portion do not overlap each other and the cover portion encompasses the explosion-proof valve.

Abstract: An image forming apparatus includes a rotatable photosensitive member, a charging member, an exposure unit, a developing member, a transfer member, and a pre-exposure unit. The pre-exposure unit exposes a surface of the photosensitive member after the toner image is transferred to the recording material and before being charged by the charging member. The pre-exposure unit includes a substrate disposed adjacent to one end of the photosensitive member with respect to a longitudinal direction of the photosensitive member, and in which a first light emitting element and a second light emitting element having directional characteristics narrower than that of the first light emitting element are mounted.

Abstract: A Schottky barrier diode includes a semiconductor substrate made of gallium oxide, a drift layer made of gallium oxide and formed on the semiconductor substrate, an anode electrode brought into Schottky contact with the drift layer, a cathode electrode brought into ohmic contact with the semiconductor substrate, an insulating film covering the inner wall of a trench formed in the drift layer, and a protective film covering the anode electrode, wherein a part of the protective film is embedded in the trench. The part of the protective film is thus embedded in the trench, so that adhesion performance between the anode electrode and protective film is enhanced. This makes it possible to prevent peeling at the boundary between the anode electrode and the protective film.

Abstract: An object of the present invention is to provide a Schottky barrier diode less liable to cause dielectric breakdown due to concentration of an electric field. A Schottky barrier diode according to this disclosure includes a semiconductor substrate made of gallium oxide, a drift layer made of gallium oxide and provided on the semiconductor substrate, an anode electrode brought into Schottky contact with the drift layer, and a cathode electrode brought into ohmic contact with the semiconductor substrate. The drift layer has an outer peripheral trench surrounding the anode electrode in a plan view. The surface of the drift layer positioned between the anode electrode and the outer peripheral trench is covered with a semiconductor layer having a conductivity type opposite to that of the drift layer.

Abstract: The switching circuit includes a first capacitor to which a pulse signal output from a control unit is input, a rectification circuit including at least a first diode and a second diode, the rectification circuit rectifying a voltage input from the first capacitor, and generating a first voltage, and a first switching element including a first terminal, a second terminal and a third terminal, the first voltage generated by the rectification circuit being applied between the first terminal and the second terminal.

Abstract: A die for EFG-based single crystal growth includes a lower surface to be immersed into a raw material melt with an impurity added, a rectangular upper surface facing a seed crystal and having a long side and a short side, and a plurality of slit sections extending from the lower surface to the upper surface and causing the raw material melt to ascend from the lower surface to the upper surface. Respective longitudinal directions of openings of the plurality of slit sections on the upper surface are parallel to one another and non-parallel to the long side of the upper surface.

Abstract: An object of the present invention is to provide a Schottky barrier diode less apt to cause dielectric breakdown due to concentration of an electric field. A Schottky barrier diode includes a semiconductor substrate 20 made of gallium oxide, a drift layer 30 made of gallium oxide and provided on the semiconductor substrate 20, an anode electrode 40 brought into Schottky contact with the drift layer 30, and a cathode electrode 50 brought into ohmic contact with the semiconductor substrate 20. The drift layer 30 has an outer peripheral trench 10 that surrounds the anode electrode 40 in a plan view, and the outer peripheral trench 10 is filled with a semiconductor material 11 having a conductivity type opposite to that of the drift layer 30. An electric field is dispersed by the presence of the thus configured outer peripheral trench 10. This alleviates electric field concentration on the corner of the anode electrode 40, making it less apt to cause dielectric breakdown.

Abstract: In a crystal manufacturing method, first, a feedstock including a tapered tip portion is disposed above a crystal growth region. Then, a side surface of the tip portion is selectively heated and melted by radiant heat traveling diagonally upward while a shape of the tip portion is maintained, and the side surface of the tip portion is physically connected to an upper surface of the crystal growth region by a material melted from the side surface. In a crystal manufacturing apparatus, the radiant heat for melting the feedstock is radiated from an electric resistance heater.

Abstract: A trench MOS Schottky diode includes a first semiconductor layer including a Ga2O3-based single crystal, a second semiconductor layer that is a layer stacked on the first semiconductor layer, includes a Ga2O3-based single crystal, and includes a trench opened on a surface thereof opposite to the first semiconductor layer, an anode electrode formed on the surface of the second semiconductor layer, a cathode electrode formed on a surface of the first semiconductor layer, an insulating film covering the inner surface of the trench of the second semiconductor layer, and a trench electrode that is buried in the trench of the second semiconductor layer so as to be covered with the insulating film and is in contact with the anode electrode. The second semiconductor layer includes an insulating dry-etching-damaged layer with a thickness of not more than 0.8 ?m in a region including the inner surface of the trench.