A semi-insulating compound semiconductor substrate includes a semi-insulating compound semiconductor, the semi-insulating compound semiconductor substrate being configured such that, on a major plane having a plane orientation of (100), a standard deviation/average value of specific resistance measured at intervals of 0.1 mm along equivalent four directions in a <110> direction from a center of the major plane, and a standard deviation/average value of specific resistance measured at intervals of 0.1 mm along equivalent four directions in a <100> direction from the center of the major plane are each not more than 0.1.

A furnace includes a pedestal, a crucible, first and second heaters, and a controller. The crucible is arranged on a pedestal that is movable downwardly and is rotatable. The first and second heaters are spaced vertically along an outer wall of the crucible and are arranged around the crucible to heat pieces of solid material deposited in the crucible. A third heater is arranged above the crucible if the crucible includes a solid cylindrical mold or in a hollow cylindrical space of the crucible if the crucible includes a hollow cylindrical mold. The controller is configured to control the first and second heaters to heat the pieces of the solid material to form a melted liquid. The controller is configured to control the rotational and downward movements of the pedestal relative to the first and second heaters during solidification of the melted liquid to form an ingot.

A crucible includes an outer element and an inner element. The outer element includes a first portion that is horizontal at a bottom end of the crucible and a second portion that ascends radially outwardly from the bottom end of the crucible to a top end of the crucible at a first acute angle to a vertical axis. The inner element includes a conus with a cylinder at a base of the conus. The conus descends radially outwardly from the top end of the crucible to the bottom end of the crucible at a second acute angle to the vertical axis. The inner element includes a base portion of the cylinder attached to the first portion of the outer element using a sealant to form a hollow mold between an inner portion of the outer element and an outer portion of the inner element.

A device (1, 1, 1) for manufacturing III-V-crystals and wafers (14) manufactured therefrom, which are free of residual stress and dislocations, from melt (16) of a raw material optionally supplemented by lattice hardening dopants comprises a crucible (2, 2, 2) for receiving the melt (16) having a first section (4, 4) including a first cross-sectional area and a second section (6) for receiving a seed crystal (12) and having a second cross-sectional area, wherein the second cross-sectional area is smaller than the first cross-sectional area and the first and second sections are connected with each other directly or via third section (8, 8) which tapers from the first section towards the second section, in order to allow a crystallization starting from the seed crystal (12) within the directed temperature field (T) into the solidifying melt. The first section (4, 4) of the crucible (2, 2, 2) has a central axis (M), and the second section (6) is arranged being offset (v) with regard to the central axis (M) of the first section (4, 4).

Apparatus and methods used in the manufacture of glass articles, the apparatus and methods including a surface of crystal zirconia are disclosed. Methods of making glass articles utilizing the apparatus and methods of manufacturing the apparatus are also disclosed.

A container for silicon ingot fabrication and a manufacturing method thereof are provided. The method includes the following steps. A base layer made of quartz is provided in a chamber. A powder solution layer is coated over an inner surface of the base layer. The powder solution layer includes silicon nitride or carbon. The base layer having the powder solution layer coated thereon is heated to a temperature of 1000 C. to 1700 C. while a reaction gas is supplied into the chamber for 2 hours to 8 hours to form a barrier layer over the inner surface of the base layer. The barrier layer includes silicon oxynitride represented by Si.sub.xN.sub.yO.sub.z, 1x2, 1y2, and 0.1z1. Moreover, a method for manufacturing a crystalline silicon ingot is also provided.

A process for casting a single crystal axis-symmetric thick walled tube comprising forming a axisymmetric single crystal ring seed around a circular internal core, wherein the ring seed has an inner diameter and a taper on the inner diameter, and wherein the internal core has an outer diameter and a matching taper on the outer diameter, the matching taper matching the taper of the inner diameter of the ring seed, and the internal core being free to translate in a vertical direction relative to the ring seed; and heating the ring seed so as to expand the ring seed relative to the internal core, and allowing the circular internal core to translate relative to the ring seed in a direction of the force of gravity, thereby maintaining contact between the circular internal core and the ring seed.

A single-crystalline metal is created on a substrate by liquefying a metal material contained within a crucible while in contact with a surface of the substrate, cooling the metal material by causing a temperature gradient effected in the substrate in a direction that is neutral along the surface of the substrate and, therein, growing the single-crystalline metal in the crucible.

A semiconductor wafer forms on a mold containing a dopant. The dopant dopes a melt region adjacent the mold. There, dopant concentration is higher than in the melt bulk. A wafer starts solidifying. Dopant diffuses poorly in solid semiconductor. After a wafer starts solidifying, dopant cannot enter the melt. Afterwards, the concentration of dopant in the melt adjacent the wafer surface is less than what was present where the wafer began to form. New wafer regions grow from a melt region whose dopant concentration lessens over time. This establishes a dopant gradient in the wafer, with higher concentration adjacent the mold. The gradient can be tailored. A gradient gives rise to a field that can function as a drift or back surface field. Solar collectors can have open grid conductors and better optical reflectors on the back surface, made possible by the intrinsic back surface field.

A system comprises a silicon seed arranged on a pedestal, where the silicon seed is ring shaped and is configured to receive melted silicon at a feed rate to form an ingot, and where the pedestal is configured to rotate at a rotational speed. A controller is configured to, while the silicon seed receives the melted silicon and while the ingot is forming: receive feedback regarding a diameter of the ingot and regarding an angle of a meniscus of the ingot, and control the rotational speed of the pedestal and the feed rate of the melted silicon based on the feedback to control the diameter of the ingot and the angle of the meniscus of the ingot.