Abstract: Methods and apparatus, including computer program products, for processing documents in a workflow system with users external to the system.

Abstract: Methods and apparatus, including computer program products implement techniques for validating programs. A language-independent description of a computer program is received, and the language-independent description is validated. The language-independent description includes a definition module and an implementation module. A language-dependent program is generated from the language-independent description, where the language-dependent program includes an interface and a class, and the language-dependent program is validated.

Abstract: A Schottky diode has a Schottky junction formed by a thin metal layer and/or metal silicide layer at the top side of a doped well in a semiconductor body or substrate. In contrast to the fabrication of low-impedance contacts on CMOS wells, a metal, to be precise titanium in the preferred embodiment, is applied not to a highly doped contact region but to the lightly doped semiconductor material of the doped well, for example an HV well for the fabrication of high-voltage transistors.

Abstract: Semiconductor material has a low metal concentration at the surface. The semiconductor material has an iron content and/or chromium content on the surface of less than 6.66×10−11 g/cm2. A method for producing this semiconductor material includes a preliminary cleaning, a main cleaning and hydrophilization. A device for use in this method has a container with pyramid-shaped recesses at the bottom.

Abstract: A novel material can be obtained by chemical reaction from elemental or alloyed silicon powder, to which fillers are optionally added. The novel material, which can be worked mechanically, can be further refined by means of subsequent heat treatment and/or surface coating, and can in many cases be used instead of polycrystalline or sintered silicon.

Abstract: A ceramic material made of a skeleton reaction-bonded silicon powder is distinguished by an open-cell pore structure produced by using a matrix of an appropriately shaped polyurethane foam structure. For the preparation, a foam matrix is coated with a suspension of silicon powder, synthetic resin and solvent and is subjected to a heat treatment, during which the foam matrix is expelled and the silicon is stabilized. The thermally and chemically stable product can be used, for example, as a filter medium for metal melts, as a catalyst carrier, or as a boundary medium between the flame zone and unignited combustible mixtures in burners.

Abstract: A method for lowering the risk of contamination during comminution of solid silicon fragments produces in a first step a temperature gradient in the solid silicon fragments. This temperature gradient results from the action of heat applied from the outside. A second temperature gradient is then produced, whose direction is rapidly at least partly reversed in a second step. This treatment effects a decompacting which makes it possible to use, in a subsequent mechanical comminution step, tools whose contact surfaces are composed of silicon or of hard materials, for example, based on nitride or carbide. The product obtained is remarkable for its uniform grain size distribution and also for its high purity in fine grain size categories. In addition, the low forces required for the comminution makes possible a longer service life for the tools used.

Abstract: A process for continuous or batchwise melting of silicon powder in particular, powder having a large amount of fines, and a melting crucible for carrying out this process are specified. The melting crucible is designed so that a melt pool having a certain minimum height and which is covered by unmelted silicon powder is provided. Thus, added material first comes into contact with silicon powder which is already present and only gradually reaches the melting zone. The amount of melt produced which exceeds the minimum height of the melt pool flows out of the melting crucible. The minimum height is maintained in the process by using a crucible which has a siphon-like outlet in the base.

Abstract: A process for preparing molded bodies of granular material of silicon, germanium or mixed crystals of these elements. The granular material is introduced into a defined three dimensional mold and a chemical transport reaction is started which proceeds with the transport of silicon or germanium. As a result, the particles of the granular material intergrow with each other and eventually form a solid, porous molded body. By varying the starting material, the transport agent, and by adding dopants, the electrical properties of the product can be varied.

Abstract: A process for the purification of silicon by the action of one or several acids, wherein silicon is established as a stationary phase and one or several acids are caused to form mobile phases for traversing the stationary phase under pressure and absorbing the impurities from the silicon during the passage, leaving behind the silicon with a higher degree of purity.

Abstract: The slag portion can easily be removed from molten mixtures of slag and silicon by subjecting such mixtures to a hydrostatic pressure difference with respect to a space separated from them by one or more separating walls of graphite or silicon carbide, preferably provided with circular to slot-shaped apertures. Such separating walls are permeable to both the slag and silicon when present alone, but permeable only to the slag when a molten mixture of slag and silicon is present.

Abstract: Pure silicon is obtained in a semicontinuous process by reducing quartz sand with aluminum in a slag medium based on alkaline earth metal silicates. The slag serves thereby simultaneously as a solvent for the aluminum oxide that forms and as an extraction medium for impurities that occur. The silicon formed separates out of the silicate slag and can be separated off. The aluminum oxide produced by the reduction can be separated from the slag and used for recovery of reusable aluminum.

Abstract: Competitive current generation by the exploitation of solar energy requires cheap solar cells. A process is described which makes it possible to manufacture from silicon a base material for solar cells of this type in an economical manner and in large quantities. This is achieved by bringing silicon from a supply container into contact with a non-elemental lubricating melt, which is immiscible with silicon but will not wet silicon and has a melting point below that of silicon, and by drawing off a silicon film, sliding on this lubricating melt, and solidifying the silicon continuously by cooling to below its' melting point.

Abstract: Pure silicon is obtained in a cyclic process by reducing quartz sand with aluminum; the finely divided quartz is dissolved in an aluminum sulphide slag and is reduced by molten aluminum. The molten aluminum also serves as a solvent for the elemental silicon which crystallizes out and precipitates as the temperature falls. Aluminum oxide formed during the reduction is extracted from the slag and passed on for melt electrolysis in order to recover the aluminum.

Abstract: A method of purifying metallurgical-grade silicon for the production of silicon solar cells is provided, in which metallurgical-grade silicon is dissolved in aluminum and brought into contact with an aluminum sulphide extraction melt. Thereafter, the silicon is crystallized out and separated off by cooling the melt to a minimum temperature of 600.degree. C. The aluminum melt remaining can then be recharged with silicon, heated, brought into contact with the extraction melt, so that additional silicon can be crystallized out.

Abstract: A process is provided for purifying metallurgical-grade silicon for the manufacture of solar cells, wherein the acid treatment of the silicon, known per se, is combined with vacuum evaporation. This may be optionally combined with slag extraction and directional solidification.

Abstract: A process for protecting carbon bodies against attack by molten silicon by applying a separating protective layer is provided which is characterized in that a separating layer is applied to the surface of the carbon body to be protected in such a manner as to wet it. The separating layer consists of alkaline earth metal fluorides in admixture with 0 to 90 mole % of alkaline earth metal silicates having a melting point lower than that of silicon.

Abstract: A process for making a homogeneous solidified alloy having at least one component with a comparatively high vapor pressure, in which the alloy components are enclosed in the form of a homogeneous melt in a sealed ampoule and cooled therein, the volume free of melt in said ampoule being during the entire cooling step of the melt between 0.001 and 1 cc, and the ratio of the volume of the ampoule free of melt and that of the ampoule filled with melt is not larger than 1:5.