Abstract: Crystalline rods or blocks can be sawed into thin wafers by sawing the rod r block into a plurality of wafers that are connected to each other. The wafers can be connected by introducing a connecting agent after each sawing step, into the resulting cutting gaps. The wafers are separated only after the whole rod has been sawed. The method makes possible the use of multiple-blade internal-hole saws, and preferably two-blade internal-hole saws.

Abstract: The chlorosilanes contained in the residual gases obtained in the deposit of silicon and in the conversion of silicon tetrachloride are first condensed out in liquid form. The hydrogen chloride present in the residual gases is dissolved in the condensed silicon tetrachloride. The remaining, virtually pure hydrogen is passed back into the process. During the distillation of the condensate, the dissolved hydrogen chloride is removed and can be separated off and reused. The trichlorosilane obtained after the distillation and the silicon tetrachloride can also be reused in the deposition process or the conversion process, respectively.

Abstract: Surfaces of III-V-semiconductors, especially gallium phosphide surfaces, can be polished very successfully if, in the polishing operation, an alkali metal hypochlorite solution adjusted to a pH value of from 8.5 to 11 by the addition of buffering components, and a liquid containing in addition to the mechanical polishing component a complex-forming component, are applied to the surface to be polished.

Abstract: A process and apparatus for supporting crystalline wafers utilizing the sion effect of flowing gas on the crystalline wafers. An almost point-like support of the crystalline wafer is achieved. Furthermore, the invention relates to a holding tool for carrying out the process, which tool has at the center of the holding face, a point-like projection.

Abstract: Indium phosphide surfaces can be polished if, during the mechanical polishing operation, which is carried out in a customary manner, a component that yields free chlorine in an aqueous acidic medium, and, at the same time, a component that yields free carbon dioxide are applied to the surface to be polished.

Abstract: A process for producing high purity silicon semiconductor materials and mls by the thermal decomposition of a gaseous compound containing the silicon semiconductor material or metal passing over silicon carrier bodies heated by an external electrical power source. The silicon carrier bodies are arranged into groups coupled in parallel electrical connection across the power source during the start of the deposition process. An equal amount of electrical current is passed through each of the groups of the parallel connection to heat the carrier bodies to deposition temperature. The same current flows in each of the parallel carrier groups by using a current-divider inductor having a winding connected to each group.

Abstract: In the crucible-pulling of crystalline rods by the Czochralski technique, pulling plants that operate with a radiation screen offer a number of advantages. This process is optimized according to the invention by the use of a radiation screen which is joined to a lifting and pivoting mechanism that can be operated throughout the entire pulling process, and which is brought into position above the melt only when the contents of the crucible have been melted.

Abstract: In the crucible pulling of silicon according to the Czochralski technique, ilicon monoxide forms as a result of the silicon melt reacting with the quartz crucible containing the melt, and evaporates and deposits in the form of solid particles on the upper edge of the crucible, on the monocrystalline rod, on the walls of the vessel, and also on recharging devices in the upper pulling chamber. These solid particles can fall back into the melt and then cause dislocations and polycrystalline growth in the growing silicon rod. As a result of the reaction of the carbon of the hot graphite parts with silicon monoxide, carbon monoxide is also formed and this partially diffuses into the melt and gives rise to carbon impurities in the silicon rod. In addition, because of heat irradiation from the inner wall of the quartz crucible as it becomes more empty, high pulling speeds, such as those usual in crucible-free zone pulling, cannot be obtained.

Abstract: The invention relates to a method and device for making pure semiconductor aterial by thermal decomposition of compounds of the semiconductor material on suitable carrier elements. The quantity and quality of the obtained semiconductor material is increased in accordance with the invention by introducing the compounds to be decomposed into the reactor chamber in at least a partially liquid state through a nozzle having a plurality of discharge openings.

Abstract: Process for cementing semiconductor discs to a carrier plate for subsequent olishing, which comprises applying to the discs a cementing solution being composed of(a) a resin of a melting range between 50.degree. and 180.degree. C. and a melt viscosity between 1000 and 6000 P;(b) a substance acting as plasticizer for the resin at cementing temperatures; and(c) a solvent for the resin and the plasticizer, which evaporizes at cementing temperatures,while avoiding during the application the occlusion of air bubbles between discs and cementing layer, and exerting pressure onto the plates at a temperature between cementing temperatures and 30.degree. C. below the same. The invention also comprises the carrier plate carrying one or more discs cemented thereto by the above process.

Abstract: An apparatus and process for cementing semiconductor discs onto a carrier ate, wherein after the carrier plate is coated with a layer of adhesive substance, the discs are applied to the adhesive layer and a vacuum-tight sealing dome is placed over the carrier plate to define a sealed, hollow space. A chemically-inert elastic diaphragm is clamped within the dome 0.2 to 1.5 mm above the free surface of the discs, to divide the hollow space into two sections or subchambers which are initially simulataneously evacuated. Then, air pressure is applied to the upper section, so that the discs are pressed by the diaphragm onto the cement layer. Air pressure is then subsequently fed to the lower hollow space, so that the dome can be removed from the carrier plate.

Abstract: In conventional polishing machines, uneven transmission of pressure causes ifferent degrees of abrasion of the polished discs which results in different thicknesses over one disc and also with respect to other discs in one polishing batch. This problem is solved according to the invention by the provision of soft elastic inserts between the pressure piston and the back of the carrier plate on which the discs to be polished are cemented.

Abstract: A process for decreasing crystal damages in the production of n-doped silicon by neutron bombardment, in which phosphorus atoms are formed from silicon by nuclear transmutation, wherein the number of desired phosphorus atoms N.sub.31.sbsb.p per cc, can be calculated by the known equationN.sub.31.sbsb.p =N.sub.30.sbsb.Si .multidot..sigma..multidot..phi..multidot.tin which N.sub.30.sbsb.Si is the number of .sup.30 Si-isotopes per cc, .sigma.=0.13 barn effective cross section, .phi. the flux density of the thermal neutrons per cm.sup.2 and t the bombardment time in seconds, the process consisting of adjusting the ratio between thermal and fast neutrons in the neutron flux acting upon the bombarded silicon work piece, so that the higher the ratio, the higher the specific resistance of the bombarded silicon, and thus, the lower the number of N.sub.31.sbsb.p and therewith the acting dose .phi..multidot.t.

Abstract: A process for working up hydrolyzable and/or water-soluble compounds by ping them in water is provided wherein the compounds are fed into the funnel of a rotating cone of water running down into the tip of the cone, with the water being constantly renewed by a supply at the base of the cone. The process is particularly useful for working up mixtures containing silanes and/or chlorosilanes in silicon deposition plants.

Abstract: A lap cutting abrasive for use with lap cutting blades, comprising one part y weight of a low viscosity carrier liquid, and one to three parts by weight of cutting particles having an average size of from 10 to 50 .mu.m suspended in the carrier liquid. The carrier liquid has a viscosity of from 1 to 10 cP, and preferably is aqueous glycerin. The cutting particles preferably have an average particle size of from 15 to 30 .mu.m. In a further embodiment, the average particle size of the cutting particles is matched to the thickness of the lap cutting blade used during sawing. Preferably, the cutting particles have an average particle size corresponding to 0.15 to 0.1 times the thickness of the lap cutting blade used during sawing.

Abstract: The invention provides a process according to which the oxygen content in ucible-drawn silicon crystals can be lowered and kept substantially constant throughout the length of the rod. This is achieved in that, after applying the seed crystal to the melt pool, the silicon rod being drawn from the melt pool is initially rotated at a speed from 3 to 6 rev/min and this rotational speed is preferably increased to higher values during the drawing process.

Abstract: A process for purifying solid substances by melting and subsequent resoliication, wherein a melted bath of the solid substance is formed, a roller is placed in the bath so that a first portion of its surface is in contact with the melted substance, and the surface of the roller is cooled to a temperature below the melting point of the solid substance. The cooled roller is rotated in the melted substance to collect a solidified film of the substance on the roller surface. A second portion of the roller surface is passed through a heated zone at a temperature above the melting point of the solid substance, so that the solidified film is remelted and collected in an appliance.

Abstract: A process for producing high purity semiconductor materials and metals by ermal decomposition of a gaseous compound of said materials, comprising the steps of arranging conductive carrier bodies in electrical current branches in a multi-phase a.c. system, then passing an equal amount of electrical current through each of the branches so as to heat the carrier bodies to deposition temperature, regulating the current in each of the branches so that the same magnitude of current flows through each branch.

Abstract: The invention provides a process and an apparatus for machining silicon r and tubes by abrasion. The risk of fracture of such workpieces during grinding is prevented in this method and apparatus by the workpiece being held vertically in a cylindrical grinding machine in which the individual tools are uniformly arranged around the circumference of the workpiece in such a manner that their contact pressures are mutually substantially compensated.

Abstract: A process for determining the effective doping agent content of hydrogen the production of semiconductors which comprises zone drawing a silicon rod of highest purity and having a known specific resistance, in the presence of hydrogen to be tested, subsequently redetermining the specific resistance of the silicon rod, and computing the concentration of the doping agent in the hydrogen used from the known relationship between the specific resistance and the amount of doping agent. By stepwise determination of the resistance along the longitudinal axis of the rod, the amount of doping agent built into the rod at different levels can thus be determined.