Abstract: Improvements in apparatus for zone refining polycrystalline semiconductor rods to produce monocrystalline semiconductor rods are disclosed. In the apparatus, an inductive heating chamber is employed which has a longitudinal dimension independent of the length of the polycrystalline semiconductor rod to be processed. The longitudinal dimension of the induction heating chamber is limited only by considerations of the space required for the RF induction heating coil and related apparatus which must be mounted within the chamber, the viewing space required for the operator to observe the zone refining process, and the heating effect on the structures above and below the chamber. First and second gas tight bellows are provided which, respectively, surround the rod holder and the seed holder.

Abstract: Method for producing virtually perfect massive unicrystalline gadolinium gallium garnet from a melt of gadolinium and gallium oxides containing an addition of calcium, magnesium or strontium ions.

Abstract: The growth of a solid obtained by cooling a liquid solution is observed and controlled by measuring the variation in volume of the solid-liquid system at the time of solidification. The method is applicable to the control of oriented crystallization from an initial crystal seed or epitaxial growth on a substrate having a suitable crystal orientation. The rate of crystallization can be controlled by means of a furnace provided with means for producing regulated thermal gradients, temperature-measuring means, a chamber filled with an inert liquid, an open-topped container filled with the liquid to be solidified and immersed in the inert liquid, the container being suspended from one arm of the beam of an electrobalance.

Abstract: Refractory tubings, either in amorphous, polycrystalline or single crystal form, are made by moving a preformed tubing of a refractory material and a heated zone relative to each other, the heating zone providing sufficient heat to melt through the tubing and form a molten ring which is continuously advanced through the tubing. The heat source may be located externally or internally of the tubing wall or in both positions. The tubings may be formed as single crystals by using appropriate seeds; and by controlling the rate of movement of the tubing sections on either side of the molten ring the wall thickness and diameter of the final tubing may be adjusted.

Abstract: A polycrystalline semiconductor sheet may be converted to a monocrystalline or macrocrystalline semiconductor sheet through use of a geometric restriction in the sheet. The process requires formation of a region of the sheet having a small width compared to the width of the remainder of the sheet. A molten zone is formed in the small width region of the sheet. At least a portion of the molten zone is allowed to solidify into a single crystal or crystals of large size of the semiconductor material coextensive with the small width of the region at the portion of the molten zone so solidified. The molten zone is then moved from the small width region of the sheet into the remainder of the sheet. The sheet is allowed to solidify successively as the molten zone passes along it. As a result, the macrocrystal formed in the narrow width region of the sheet propagates into the remainder of the sheet through which the molten zone passes.

Abstract: Improvements in the dual temperature exchange system wherein the feed supply substance traverses selected portions of one of the two temperature zones, said selected portions being correlated with the availability and/or cost of a supply of the feed substance concerned; e.g.

Abstract: Apparatus for thermal control in dual temperature systems in which both liquid and gas are present together at different temperatures in different locations in the system. Hot humidified gases rather than being cooled with water are circulated in a cyclic treatment reclaiming their heat which is then used for heating and humidification of gases entering a hot tower.

Abstract: An apparatus is designed for pulling oriented large-size single crystals from melt.The apparatus comprises a hollow rod having a seed crystal holder. The rod drive comprises a drive shaft mounted in the rod coaxially therewith, the rod and the drive shaft being in engagement for combined rotation and for reciprocations of the rod together with a carriage axially along the drive shaft.

Abstract: An improved process for growing single crystals of ceramic material according to the gradient furnace technique is disclosed. The process combines the gradient furnace technique with principles of zone leveling and comprises seeding the melt of a ceramic material in a crucible, heating the crucible to above the melting point of the material and solidifying the material to form a single crystal by extracting heat from the bottom portion of the crucible. The application of zone leveling principles to this system comprises melting the ceramic material by creating a molten zone at the bottom portion of the crucible and passing the zone up the crucible to progressively melt successive portions of the ceramic material therein.

Abstract: A sample processor and method for the automatic extraction of families of compounds, known as extracts, from liquid and/or homogenized solid samples are disclosed. The sample processor includes a tube support structure which supports a plurality of extraction tubes, each containing a sample from which families of compounds are to be extracted. The support structure is moveable automatically with respect to one or more extraction stations, so that as each tube is at each station a solvent system, consisting of a solvent and reagents, is introduced therein. As a result an extract is automatically extracted from the tube. The sample processor includes an arrangement for directing the different extracts from each tube to different containers, or to direct similar extracts from different tubes to the same utilization device.

Abstract: A method is disclosed of growing a crystalline body of a selected material so that the body has a selected cross-sectional shape. The method includes the steps normally employed in known capillary die processes and further includes observing at least the portion of the surfaces of the growing crystalline body and the meniscus (of melt material from which the body is being pulled) including the solid/liquid/vapor junction in a direction substantially perpendicular to the meniscus surface formed at the junction when the growth of the crystalline body is under steady state conditions. The cross-sectional size of the growing crystalline body can be controlled by determining which points exhibit a sharp change in the amount of reflected radiation of a preselected wavelength and controlling the speed at which the body is being pulled or the temperature of the growth pool of melt so as to maintain those points exhibiting a sharp change at a preselected spatial position relative to a predetermined reference position.

Abstract: Apparatus is disclosed for controlling the growth of a crystalline body of a selected material so that the body has a selected cross-sectional shape. The apparatus includes the structure normally employed in known capillary die devices and further includes means for observing at least the portion of the surfaces of the growing crystalline body and the meniscus (of melt material from which the body is being pulled) including the solid/liquid/vapor junction in a direction substantially perpendicular to the meniscus surface formed at the junction when the growth of the crystalline body is under steady state conditions.

Abstract: An apparatus and method for the controlled chlorination of a water supply in which an alkali metal salt of dichloroisocyanuric acid is dissolved to form a concentrated chlorine solution that is slowly released into the water supply. The apparatus contains an internal standpipe, open to the water supply at its bottom end and having water inlet apertures and solution metering apertures in its wall. The natural circulation of water in the standpipe through the solid dichloroisocyanurate charge contained in the apparatus results in chlorination of the water supply at a rate controlled by the size and number of solution metering apertures.

Abstract: A method and apparatus for controlling a heated bath of molten material to obtain controlled solidification, wherein the molten bath is kept in constant rotational movement relative to the solid portion of the material being treated and the mechanical action due to the viscous friction which develops in the bath is detected and thereby controlled, said method being applicable to the floating zone method and the Czochralsky crystal drawing method and being capable of producing ingots of high dimensional regularity.

Abstract: A method of manufacturing a rod of crystalline material in a crucible formed at least partly by a fabric of refractory fibrous material.Prior to its use the crucible is subjected to a preparatory treatment consisting mainly of wetting the inner face by means of gallium.Application: Manufacture of rods of semiconductor material.

Abstract: Methods of growing crystals by the Czochralski method in which a member having a central vertical passageway extending through it is floated on the melt, and the crystallization is caused to take place within this passageway. The passageway may be parallel sided or tapering from top to bottom and is such that the melt does not wet the walls of the passageway. Excellent diameter control of the grown crystal is obtainable, and since the member floats on the melt during crystallisation, its position follows changes in the level of the melt as the material is pulled from the melt. In one embodiment, the member is porous and fluid is forced through the porous wall of the passageway from a cavity within the member to form a barrier to keep the melt out of contact with the wall of the passageway. In another embodiment, a liquid encapsulant is used, which forms a coating over the whole surface of the floating member including the wall of the passageway.

Abstract: Use of copper ion in acrylamide solution during concentration to inhibit polymerization.

Abstract: Apparatus for continuously separating sulfur from an aqueous sulfur suspension which is heated above the melting point of sulfur. The apparatus comprises a pressure vessel having heating and stirring means in its upper part, the lower part of the vessel serving as a settling tank where sulfur is precipitated out of the aqueous solution and withdrawn through an outlet in the bottom of the vessel. Intermediate the upper and lower parts of the vessel is a substantially horizontal, shallow conical partition which has apertures or slots therein to permit the suspension to pass from the upper part to the lower part. A steam-heated jacket surrounds the vessel; while pressure sensing devices are utilized to maintain the level of the water in the top part and the boundary surface between the water phase and the sulfur phase in the bottom part at desired heights.

Abstract: Apparatus for pulling a ribbon shaped crystal from a melt of the same downwardly through a shaping guide having a "V" shaped longitudinal trough for containing the melt. The inner wall of the trough is a die set having a longitudinal slit at the apex of the "V".

Abstract: A saturated solution of silicon and an element such as carbon having a segregation coefficient less than unity is formed by placing a solid piece of carbon in a body of molten silicon having a temperature differential decreasing toward the surface. A silicon carbide seed crystal is disposed on a holder beneath the surface of the molten silicon. As a rod or ribbon of silicon is slowly pulled from the melt, a supersaturated solution of carbon in silicon is formed in the vicinity of the seed crystal. Excess carbon is emitted from the solution in the form of silicon carbide which crystallizes on the seed crystal held in the cool region of the melt.