Abstract: When a SiC substrate is heated up to around 1800°C., sublimation of SiC occurs from the SiC substrate. Moreover, temperature of the front surface of the SiC substrate is lower than that of the back surface of the SiC substrate. Therefore, sublimation gas sublimed from a back-surface vicinity of the substrate, where temperature is high, moves to a front-surface vicinity of the substrate, where temperature is low, through the hollow micro-pipe defect. Epitaxial growth proceeds on the front surface of the substrate while the sublimation gas is recrystallized at the front-surface vicinity of the substrate, so that the micro-pipe defect is occluded.

Abstract: A crucible has first member and second cylindrical body, and is disposed in a lower chamber. The fist member is disposed in the second cylindrical body so as to define a gas flow path formed therebetween as a gap. A pedestal is disposed inside the first member. A seed crystal is fixed to the pedestal. SiC single crystals are formed on the pedestal by introducing a mixture gas through an inlet conduit. During growth of the SiC single crystals, conductance in introduction of the mixture gas into the crucible is larger than that in exhaust of the mixture gas, so that pressure of the mixture gas in the crucible is larger than that of the mixture gas after exhausted from the crucible.

Abstract: When a SiC substrate is heated up to around 1800° C., sublimation of SiC occurs from the SiC substrate. Moreover, temperature of the front surface of the SiC substrate is lower than that of the back surface of the SiC substrate. Therefore, sublimation gas sublimed from a back-surface vicinity of the substrate, where temperature is high, moves to a front-surface vicinity of the substrate, where temperature is low, through the hollow micro-pipe defect. Epitaxial growth proceeds on the front surface of the substrate while the sublimation gas is recrystallized at the front-surface vicinity of the substrate, so that the micro-pipe defect is occluded.

Abstract: A semiconductor device, comprising: a semiconductor substrate comprising silicon carbide of a first conductivity type; a silicon carbide epitaxial layer of the first conductivity type; a first semiconductor region formed on the semiconductor substrate and comprising silicon carbide of a second conductivity type; a second semiconductor region formed on the first semiconductor region, comprising silicon carbide of the first conductivity type and separated from the semiconductor substrate of the first conductivity type by the first semiconductor region; a third semiconductor region formed on the semiconductor region, connected to the semiconductor substrate and the second semiconductor region, comprising silicon carbide of the first conductivity type, and of higher resistance than the semiconductor substrate; and a gate electrode formed on the third semiconductor region via an insulating layer; wherein the third semiconductor layer is depleted when no voltage is being applied to the gate electrode so that said s

Abstract: A crucible for growing a single crystal therein has a seed crystal attachment portion and a peripheral portion surrounding the seed crystal attachment portion through a gap provided therebetween. The seed crystal attachment portion has a support surface for holding a seed crystal on which the single crystal is to be grown, and the support surface is recessed from a surface of the peripheral portion. The seed crystal is attached to the support surface to cover an entire area of the support surface. Accordingly, no poly crystal is formed on the seed crystal attachment portion, and the single crystal can be grown on the seed crystal with high quality.

Abstract: A silicon carbide single crystal substrate and silicon carbide raw material powder are provided in a graphite vessel. Arsenic or an arsenic compound is added to the silicon carbide raw material powder. A mixed gas obtained by mixing a gas containing arsenic with a raw material gas formed by heat sublimation of the silicon carbide raw material powder is supplied to the silicon carbide single crystal substrate to grow a silicon carbide single crystal containing arsenic. Arsenic as an n-type dopant controls the resistivity of the silicon carbide single crystal. Because it has an atomic radius equivalent to silicon, it does not compress or expand the crystal, whereby crystalline distortion is less likely to occur. As a result, formation of heterogeneous polymorphism is suppressed.

Abstract: When a SiC substrate is heated up to around 1800° C., sublimation of SiC occurs from the SiC substrate. Moreover, temperature of the front surface of the SiC substrate is lower than that of the back surface of the SiC substrate. Therefore, sublimation gas sublimed from a back-surface vicinity of the substrate, where temperature is high, moves to a front-surface vicinity of the substrate, where temperature is low, through the hollow micro-pipe defect. Epitaxial growth proceeds on the front surface of the substrate while the sublimation gas is recrystallized at the front-surface vicinity of the substrate, so that the micro-pipe defect is occluded.

Abstract: A crucible, which has first member and second cylindrical body, is disposed in a lower chamber. A pedestal is disposed inside the first member, and a seed crystal is fixed to the pedestal. A second heat insulator is provided between an inlet conduit and a crucible. A first heat insulator is provided at a halfway portion of the inlet conduit. With these heat insulators, a temperature gradient occurs in the inlet conduit at a portion thereof that is closer to the crucible. A mixture gas is introduced into the crucible. The mixture gas is heated up gradually when passing through the inlet conduit and is introduced into the crucible to form SiC single crystals in high quality.

Abstract: A crucible has first member and second cylindrical body, and is disposed in a lower chamber. The fist member is disposed in the second cylindrical body so as to define a gas flow path formed therebetween as a gap. A pedestal is disposed inside the first member. A seed crystal is fixed to the pedestal. SiC single crystals are formed on the pedestal by introducing a mixture gas through an inlet conduit. During growth of the SiC single crystals, conductance in introduction of the mixture gas into the crucible is larger than that in exhaust of the mixture gas, so that pressure of the mixture gas in the crucible is larger than that of the mixture gas after exhausted from the crucible.

Abstract: A metal matrix composite casting comprises a metal matrix composite and a processed member inserted in the metal matrix composite by enveloped casting. By the processed member which is easier to process than the metal matrix composite, a processed portion of a predetermined shape can be formed in the metal matrix composite. That is, by a simple processing such that the processed member is removed from the metal matrix composite or the processed portion is formed in the processed member itself, the processed portion having a desired shape can be easily formed in the metal matrix composite.

Abstract: Micropipe defects existing in a silicon carbide single crystal are closed within the single crystal. At least a portion of the micropipe defects opened on the surface of the silicon carbide single crystal (SiC substrate) is sealed up with a coating material. Then heat treatment is performed so as to saturate the inside of the micropipe defects with silicon carbide vapors. By this, the micropipe defects existing in the SiC substrate can be closed within the SiC substrate, not in a newly grown layer. Further, the micropipe defects can be efficiently closed by filling the micropipe defects with a silicon carbide material by preliminarily using super critical fluid and the like.

Abstract: A n.sup.- -type source region 5 is formed on a predetermined region of the surface layer section of the p-type silicon carbide semiconductor layer 3 of a semiconductor substrate 4. A low-resistance p-type silicon carbide region 6 is formed on a predetermined region of the surface layer section in the p-type silicon carbide semiconductor layer 3. A trench 7 is formed in a predetermined region in the n.sup.+ -type source region 5, which trench 7 passes through the n.sup.+ -type source region 5 and the p-type silicon carbide semiconductor layer 3, reaching the n.sup.- -type silicon carbide semiconductor layer 2. The trench 7 has side walls 7a perpendicular to the surface of the semiconductor substrate 4 and a bottom side 7b parallel to the surface of the semiconductor substrate 4. The hexagonal region surrounded by the side walls 7a of the trench 7 is an island semiconductor region 12.

Abstract: A (111) cubic silicon carbide single-crystal layer is formed on a (111) silicon wafer, and then the silicon wafer is removed. Thus prepared (111) cubic silicon carbide single-crystal layer is disposed in a graphite crucible to function as a seed crystal. Silicon carbide source material powder is also held in the graphite crucible and sublimated in an atmosphere including inert gas, while controlling a temperature of the (111) cubic silicon carbide single-crystal layer to be lower than a temperature of the silicon carbide source material powder. As a result, a (0001) .alpha.-type silicon carbide single-crystal layer can be formed on the (111) cubic silicon carbide single-crystal layer with a large diameter and high quality at low cost.

Abstract: An electro-luminescent display apparatus which is capable of displaying two kinds of images is disclosed. The apparatus has a front and a rear electro-luminescent unit therein, and the green light emitted from the front unit directly displays the real image which looks close to a viewer while the orange light emitted from the rear unit is reflected by a reflector disposed at the back of the apparatus and displays a virtual image which looks far from the viewer. In order to reflect the light emitted backward from the front unit and the light emitted forward from the rear unit, reflecting electrodes are provided on the rear surface of the front unit or a reflecting film is disposed in the space between the front and the rear units.

Abstract: White light projected from a white light source is divided into three light beams of primary colors, i.e., red, green and blue by a dichroic mirror. Three light beams projected from the dichroic mirror are made incident upon a micro-lens array and reflected on and modulated in a liquid crystal panel disposed beneath the micro-lens array. The liquid crystal panel is driven by a driver circuit which supplies color signals to the panel, thereby modulating the light beams in the panel. The modulated light beams are projected from the micro-lens array to a schlieren diaphragm which eliminates scattered light components from the light beams. The light beams then enter into a projection lens and display color images on the screen. Since light beams constituting a picture element consisting of red, green and blue colors are projected from a single micro-lens of the micro-lens array, a color image displayed on the screen has no blur among three primary colors.

Abstract: A device for detecting direction, height and intensity of a light which facilitates detection and provides high accuracy. The device includes a glass substrate, on which a resistant layer for detecting the X coordinate position, a photoconductive layer utilizing the photoconducting effect of a photoelectric converting layer, and a resistant layer of metallic electrode resistor body for detecting the Y coordinate position, laminated in order. The resistant layers are provided respective two lead electrodes X, X' and Y, Y'. By applying 5V and 0V, for example, to X and X', a voltage Vx corresponding to the position where the light is irradiated can be directly obtained through Y or Y'. Namely, the X coordinate position of the point where the light passes can be easily and accurately detected. By applying +5V and 0V for Y and Y', Y coordinate of the light irradiated point can be obtained, and by applying the same potential to X and X', light intensity can be obtained.