Abstract: The present invention provides a dental product comprising a base material formed of a zirconia sintered body, and having high aesthetic quality with enhanced fracture toughness and with reduced chipping and cracking in the porcelain layer. The present invention also provides a method for manufacturing such a dental product. The present invention relates to a dental product comprising: a base material formed of a zirconia sintered body, and a porcelain layer, wherein the porcelain of the porcelain layer has a suitable firing temperature of 900° C. or more, and the porcelain layer has a fracture toughness value of 1.20 MPa·m0.5 or more.

Abstract: The present invention provides a silicate glass that can reduce a color change in base material zirconia even when simultaneously fired with an unsintered zirconia. The present invention also provides a dental product using same. The present invention relates to a silicate glass comprising: 65.0 to 90.0 mol % SiO2, 4.0 to 15.0 mol % Al2O3, 1.0 to 10.0 mol % K2O, 0.1 to 7.0 mol % Na2O, and 0.01 to 15.0 mol % CaO, the silicate glass being essentially free of B2O3, and satisfying the relation {(number of moles of Al2O3)/(total number of moles of RO+R2O)}?0.70, wherein R in the metal oxide represented by RO represents a metallic element in group 2 or 12 of the periodic table, and R in the metal oxide represented by R2O represents a metallic element in group 1 of the periodic table. The present invention also relates to a composite comprising the silicate glass and a base material formed of a ceramic; a sintered body as a fired product of the composite; and a dental product comprising the sintered body.

Abstract: The present invention provides a silicate glass that can reduce a color change in base material zirconia even when simultaneously fired with an unsintered zirconia. The present invention also provides a dental product using same. The present invention relates to a silicate glass comprising: 65.0 to 90.0 mol % SiO2, 4.0 to 15.0 mol % Al2O3, 1.0 to 10.0 mol % K2O, 0.1 to 7.0 mol % Na2O, and 0.01 to 15.0 mol % CaO, the silicate glass being essentially free of B2O3, and satisfying the relation {(number of moles of Al2O3)/(total number of moles of RO+R2O)}?0.70, wherein R in the metal oxide represented by RO represents a metallic element in group 2 or 12 of the periodic table, and R in the metal oxide represented by R2O represents a metallic element in group 1 of the periodic table. The present invention also relates to a composite comprising the silicate glass and a base material formed of a ceramic; a sintered body as a fired product of the composite; and a dental product comprising the sintered body.

Abstract: The present invention provides a dental product comprising a base material formed of a zirconia sintered body, and having high aesthetic quality with enhanced fracture toughness and with reduced chipping and cracking in the porcelain layer. The present invention also provides a method for manufacturing such a dental product. The present invention relates to a dental product comprising: a base material formed of a zirconia sintered body, and a porcelain layer, wherein the porcelain of the porcelain layer has a suitable firing temperature of 900° C. or more, and the porcelain layer has a fracture toughness value of 1.20 MPa·m0.5 or more.

Abstract: A SiC semiconductor device includes: a SiC substrate having a drain layer, a drift layer and a source layer stacked in this order; multiple trenches penetrating the source layer and reaching the drift layer; a gate layer on a sidewall of each trench; an insulation film on the sidewall of each trench covering the gate layer; a source electrode on the source layer; and a diode portion in or under the trench contacting the drift layer to provide a diode. The drift layer between the gate layer on the sidewalls of adjacent two trenches provides a channel region. The diode portion is coupled with the source electrode, and insulated from the gate layer with the insulation film.

Abstract: A silicon carbide semiconductor device includes a semiconductor element disposed in a semiconductor substrate having a first conductive type silicon carbide layer and a silicon substrate. The device includes: a trench on the silicon carbide layer to reach the silicon substrate; and a conductive layer in the trench between the silicon carbide layer and the silicon substrate to connect to both of them. The semiconductor element is a vertical type semiconductor element so that current flows on both of a top surface portion and a backside surface portion of the semiconductor substrate. The current flows through the conductive layer.

Abstract: A semiconductor device includes a vertical field-effect transistor having a substrate of first conduction type in a substrate base, a drain electrode formed on a first surface of the substrate, an epitaxial layer of first conduction type formed on a second surface of the substrate, a source region of first conduction type formed on the semiconductor base, a source ohmic contact metal film in ohmic contact with the source region, trenches formed from the second surface of the semiconductor base, and a gate region of second conduction type formed along the trenches. The semiconductor device further includes a gate rise metal film in ohmic contact with the draw-out layer of the gate region on the bottom of the trenches and rising to the second surface of the semiconductor base, and a gate draw-out metal film connected to the gate rise metal film from the second surface of the semiconductor base.

Abstract: A silicon carbide semiconductor device includes a semiconductor element disposed in a semiconductor substrate having a first conductive type silicon carbide layer and a silicon substrate. The device includes: a trench on the silicon carbide layer to reach the silicon substrate; and a conductive layer in the trench between the silicon carbide layer and the silicon substrate to connect to both of them. The semiconductor element is a vertical type semiconductor element so that current flows on both of a top surface portion and a backside surface portion of the semiconductor substrate. The current flows through the conductive layer.

Abstract: A silicon carbide semiconductor device includes a semiconductor element disposed in a semiconductor substrate having a first conductive type silicon carbide layer and a silicon substrate. The device includes: a trench on the silicon carbide layer to reach the silicon substrate; and a conductive layer in the trench between the silicon carbide layer and the silicon substrate to connect to both of them. The semiconductor element is a vertical type semiconductor element so that current flows on both of a top surface portion and a backside surface portion of the semiconductor substrate. The current flows through the conductive layer.

Abstract: A semiconductor device includes (a) a vertical field effect transistor, the vertical field effect transistor including a drain electrode formed on a first surface of a first conductivity type of a semiconductor, a pair of first trenches formed from a second surface of the semiconductor, control regions of a second conductivity type formed respectively along the first trenches, a source region of the first conductivity type formed along the second surface of the semiconductor between the first trenches, a source electrode joined to the source region, and a gate electrode adjacent to the control regions, (b) a pair of second trenches formed from the second surface of the semiconductor independently of the field effect transistor, (c) control regions of the second conductivity type formed along the second trenches, and (d) a diode having a junction formed on the second surface between the second trenches.

Abstract: A SiC semiconductor device includes: a SiC substrate having a drain layer, a drift layer and a source layer stacked in this order; multiple trenches penetrating the source layer and reaching the drift layer; a gate layer on a sidewall of each trench; an insulation film on the sidewall of each trench covering the gate layer; a source electrode on the source layer; and a diode portion in or under the trench contacting the drift layer to provide a diode. The drift layer between the gate layer on the sidewalls of adjacent two trenches provides a channel region. The diode portion is coupled with the source electrode, and insulated from the gate layer with the insulation film.

Abstract: A method of manufacturing a dental prosthesis, including: (a) a step of preparing a substrate of the dental prosthesis that is constituted by a dental molding material; (b) a step of forming a back coating layer on at least a part of a surface of the substrate, by using a first porcelain that is constituted principally by ceramic; (c) a step of forming a casting mold such that the substrate is disposed in the casting mold and such that a void is provided on a surface of the back coating layer; and (d) a step of forming a cast coating layer on at least a part of a surface of the back coating layer, by pouring a second porcelain into the void at a casting temperature. The second porcelain is constituted principally by ceramic whose composition is different from that of the ceramic of the first porcelain that viscosity of the second porcelain at the casting temperature is lower than that of the first porcelain.

Abstract: A silicon carbide semiconductor device includes a semiconductor element disposed in a semiconductor substrate having a first conductive type silicon carbide layer and a silicon substrate. The device includes: a trench on the silicon carbide layer to reach the silicon substrate; and a conductive layer in the trench between the silicon carbide layer and the silicon substrate to connect to both of them. The semiconductor element is a vertical type semiconductor element so that current flows on both of a top surface portion and a backside surface portion of the semiconductor substrate. The current flows through the conductive layer.

Abstract: A semiconductor device includes (a) a vertical field effect transistor, the vertical field effect transistor including a drain electrode formed on a first surface of a first conductivity type of a semiconductor, a pair of first trenches formed from a second surface of the semiconductor, control regions of a second conductivity type formed respectively along the first trenches, a source region of the first conductivity type formed along the second surface of the semiconductor between the first trenches, a source electrode joined to the source region, and a gate electrode adjacent to the control regions, (b) a pair of second trenches formed from the second surface of the semiconductor independently of the field effect transistor, (c) control regions of the second conductivity type formed along the second trenches, and (d) a diode having a junction formed on the second surface between the second trenches.

Abstract: A semiconductor device includes a vertical field-effect transistor having a substrate of first conduction type in a substrate base, a drain electrode formed on a first surface of the substrate, an epitaxial layer of first conduction type formed on a second surface of the substrate, a source region of first conduction type formed on the semiconductor base, a source ohmic contact metal film in ohmic contact with the source region, trenches formed from the second surface of the semiconductor base, and a gate region of second conduction type formed along the trenches. The semiconductor device further includes a gate rise metal film in ohmic contact with the draw-out layer of the gate region on the bottom of the trenches and rising to the second surface of the semiconductor base, and a gate draw-out metal film connected to the gate rise metal film from the second surface of the semiconductor base.

Abstract: A semiconductor device is provided having a power transistor structure. The power transistor structure includes a plurality of first wells disposed independently at a surface portion of a semiconductor layer; a deep region having a portion disposed in the semiconductor layer between the first wells; a drain electrode connected to respective drain regions in the first wells; a source electrode connected to respective source regions and channel well regions in the first wells, such that either the drain electrode or the source electrode is connected to an inductive load; and a connecting member for supplying the deep region with a source potential, where the connecting member is configurable to connect to the drain electrode when the drain electrode is connected to the inductive load and to connect to the source electrode when the source electrode is connected to said inductive load.

Abstract: An Al film is formed on a barrier metal covering a thin film resistor to have a first opening. A photo-resist is formed on the Al film and in the opening, and is patterned to have a second opening having an opening area smaller than that of the first opening and open in the first opening to expose the barrier metal therefrom. Then, the barrier metal is etched through the second opening. Because the barrier metal is etched from an inner portion more than the opening end of the first opening, under-cut of the barrier metal is prevented.

Abstract: The present invention provides a dental ceramic frame (10, 20, 30, 50) which is superior in terms of mechanical strength characteristics compared with conventional bridge-shaped ceramic frames that have glass joining layers or frames consisting of porous ceramics impregnated with glass.

Abstract: An Al film is formed on a barrier metal covering a thin film resistor to have a first opening. A photo-resist is formed on the Al film and in the opening, and is patterned to have a second opening having an opening area smaller than that of the first opening and open in the first opening to expose the barrier metal therefrom. Then, the barrier metal is etched through the second opening. Because the barrier metal is etched from an inner portion more than the opening end of the first opening, under-cut of the barrier metal is prevented.

Abstract: In a semiconductor device, a p-type base region is provided in an n−-type substrate to extend from a principal surface of the substrate in a perpendicular direction to the principal surface. An n+-type source region extends in the p-type base region from the principal surface in the perpendicular direction, and an n+-type drain region extends in the substrate separately from the p-type base region with a drift region interposed therebetween. A trench is formed to penetrate the p-type base region from the n+-type source region in a direction parallel to the principal surface. A gate electrode is formed in the trench through a gate insulating film. Accordingly, a channel region can be formed with a channel width in a depth direction of the trench when a voltage is applied to the gate electrode.