A crystal growing apparatus includes: a crucible which includes a main body portion, and a first portion having a radiation rate different from that of the main body portion, and is capable of controlling a temperature of a specific region inside during heating to a higher or lower temperature than that of the other regions; and a heating unit which is positioned on the outside of the crucible and is configured to heat the crucible by radiant heat, and the first portion is at a position where the crucible and a line segment connecting a heating center of the heating unit and the specific region intersect with each other.

A method of manufacturing of a vitreous silica crucible includes: fusing silica powder under a reduced pressure of −50 kPa or more and less than −95 kPa to form a transparent vitreous silica layer as an inner layer; fusing silica powder under a reduced pressure of 0 kPa or more and less than −10 kPa to form a bubble-containing vitreous silica layer as an intermediate layer; and fusing silica powder under a reduced pressure of −10 kPa or more and less than −50 kPa to form a semi-transparent vitreous silica layer as an outer layer.

A crystal growth apparatus according to the present embodiment includes a crucible, a heater which is installed on an outward side of the crucible and surrounds the crucible, and a coil which is installed on an outward side of the heater and surrounds the heater, in which an inner surface of the heater on the crucible side includes a first region, and a second region which is further away from an outer side surface of the crucible than the first region is.

A composite crucible for growing single crystals comprises an outer crucible of a first material, and an inner liner of a second material having a coefficient of thermal expansion differing from the first material. The outer crucible comprises an inside bore. The inner liner is disposed in the inside bore without diffusion bonding or chemical bonding between the outer crucible and the inner liner. In certain non-limiting embodiments, the first material is one of molybdenum and a molybdenum alloy, and the second material is one of tantalum, niobium, a tantalum alloy, and a niobium alloy.

Provided is a method for controlling the rate of etching of a SiC substrate based on a composition of a storing container. The etching method of the present invention is for etching the SiC substrate by heating the SiC substrate under Si vapor pressure, in a state where the SiC substrate is stored in a crucible. The crucible is formed of a tantalum metal, and has a tantalum carbide layer provided on an internal space side of the tantalum metal, and a tantalum silicide layer provided on the side further toward the internal space side than the tantalum carbide layer. The rate of etching of the SiC substrate is controlled based on difference in a composition of the tantalum silicide layer.

A sapphire ribbon of the present disclosure has a width, a thickness, and a length that are orthogonal to one another, a length direction is a growth direction, and the sapphire ribbon further has two main surfaces separate from each other in a thickness direction, and the width is at least 40 cm. Further, a monocrystalline ribbon manufacturing apparatus using EFG method according to the present disclosure includes a crucible having a width greater than a depth thereof, a die pair installed in the crucible and facing each other across a slit in the depth direction, a first heater and a second heater disposed around the crucible and facing each other in the depth direction, and a third heater and a fourth heater disposed around the crucible and facing each other in the width direction.

An apparatus for growing a crystal includes a growth chamber and a melt chamber thermally isolated from the growth chamber. The growth chamber includes: a growth crucible configured to contain a liquid melt; and a die located in the growth crucible, the die having a die opening and one or more capillaries extending from within the growth crucible toward the die opening. The melt chamber includes: a melt crucible configured to receive feedstock material; and at least one heating element positioned within the melt chamber relative to the melt crucible to melt the feedstock material within the melt crucible to form the liquid melt. The apparatus also includes at least one capillary conveyor in fluid communication with the melt crucible and the growth crucible to transport the liquid melt from the melt crucible to the growth crucible.

Buckling of a vitreous silica crucible 12 or inward fall of a sidewall 15 is effectively suppressed. The vitreous silica crucible 12 includes the cylindrical sidewall 15 having an upward-opening rim, a mortar-shaped bottom 16 including a curve, and a round portion 17 connecting the sidewall 15 and the bottom 16. In the vitreous silica crucible 12 the per-unit area thermal resistance in the thickness direction of the sidewall 15 is higher than that of the round portion 17.

The present invention provides a vitreous silica crucible which inhibits a deformation even when used under a high temperature condition for a long time, and a method for manufacturing the same. The vitreous silica crucible comprises: a substantially cylindrical straight body portion having an opening on the top end and extending in a vertical direction, a curved bottom portion, and a corner portion connecting the straight body portion with the bottom portion and a curvature of which is greater than that of the bottom portion, wherein, the vitreous silica crucible comprises a transparent layer on the inside and a bubble layer on the outside thereof, a compressive stress layer in which compressive stress remains in the inner surface side of the transparent layer, and a tensile stress layer in which tensile stress remains and is adjacent to the compressive stress layer at a gradual rate of change of stress.

A method of producing high strength shaped alumina by feeding alumina power into an agglomerator having a shaft with mixers able to displace the alumina power along the shaft, spraying a liquid binder onto the alumina power as it is displaced along the shaft to form a shaped alumina, and calcining the shaped alumina. The shaped alumina produced having a loose bulk density of greater than or equal to 1.20 g/ml, a surface area less than 10 m.sup.2/g, impurities of less than 5 ppm of individual metals and less than 9 ppm of impurities in total, and/or crush strength of greater than 12,000 psi.