Abstract: A method for doping a melt with a dopant has the melt being provided in a crucible. The dopant is introduced into a vessel and the vessel is immersed in the melt, the dopant being transferred into the melt through an opening which forms in the vessel. There is also an apparatus which comprises a vessel containing the dopant and a device which is connected to the vessel, for lowering the vessel into a melt and for lifting the vessel out of the melt, the vessel being provided with an opening which is blocked by a closure piece which is of the same type of material as the melt and melts when it is brought into contact with the melt.

Abstract: A method for the production of a semiconductor wafer having a front and a back and an epitaxial layer of semiconductor material deposited on the front, includes the following process steps: (a) preparing a substrate wafer having a polished front and a specific thickness; (b) pretreating the front of the substrate wafer in the presence of HCl gas and a silane source at a temperature of from 950 to 1250 degrees Celsius in an epitaxy reactor, the thickness of the substrate wafer remaining substantially unchanged; and (c) depositing the epitaxial layer on the front of the pretreated substrate wafer.

Abstract: A process for the wet chemical treatment of a semiconductor wafer in a vessel, in which the semiconductor wafer is brought into contact with a liquid in which very small gas bubbles are dispersed. Two circuits are set up for conveying the liquid, with a first circuit between a reservoir and the vessel, for conveying the liquid from the reservoir to the vessel; and with a second circuit from the reservoir back to the reservoir, in order to enrich the liquid with a gas on the way back to the reservoir, so that the gas bubbles can form.

Abstract: A process for producing a multiplicity of semiconductor wafers, which includes the following individual steps: (a) simultaneous polishing a front side and a back side of each semiconductor wafer between rotating polishing plates with a polishing fluid being supplied, the semiconductor wafer in each case resting in a cutout in a carrier and being kept on a specific geometric path, and all semiconductor wafers having a thickness t1 following the polishing; (b) assessment of each semiconductor wafer with regard to quality features which are stipulated for further processing; (c) further simultaneous polishing a front side and a back side of each of those semiconductor wafers which, according to quality inspection (b), do not satisfy the stipulated quality features, these semiconductor wafers having a thickness t2 following the further polishing; and (d) further assessment of each of those semiconductor wafers which were fed to step (c) with regard to quality features stipulated for further processing.

Abstract: A process for the surface polishing of a silicon wafer, includes the successive polishing of the silicon wafer on at least two different polishing plates covered with polishing cloth, with a continuous supply of alkaline polishing abrasive with SiO2 constituents, an amount of silicon removed during the polishing on a first polishing plate being significantly higher than on a second polishing plate, with the overall amount of silicon removed not exceeding 1.5 &mgr;m. A polishing abrasive (1a), then a mixture of a polishing abrasive (1b) and at least one alcohol, and finally ultrapure water (1c) are added to the first polishing plate, and a mixture of a polishing abrasive (2a) and at least one alcohol and then ultrapure water (2b) are added to the second plate.

Abstract: A process for the wet-chemical surface treatment of a semiconductor wafer following a mechanical surface treatment, in particular following a mechanical surface treatment in a lapping machine, includes a sequence of treatment steps. The process essentially includes a wet-chemical surface cleaning, preferably for neutralizing and eliminating the lapping slurry, an acid etching treatment, preferably for eliminating the mechanically imposed damage and for surface smoothing and removal of metals. There is a final step of drying and rendering the cleaned and etched surface hydrophilic.

Abstract: A process for the double-side polishing of semiconductor wafers between two polishing plates which rotate in opposite directions and are covered with polishing cloth, so that at least 2 &mgr;m of semiconductor material is removed. The semiconductor wafers lay in plastic-lined cutouts in a set of a plurality of planar carriers which are made from steel and the mean thickness of which is 2 to 20 &mgr;m smaller than the mean thickness of the fully polished semiconductor wafers. The set comprises only those carriers whose difference in thickness is at most 5 &mgr;m, and each carrier belonging to the set has at least one unambiguous identification feature which assigns it to the set. An item of information contained in the identification feature is used in order for the plastic linings to be exchanged at fixed intervals and to ensure that the semiconductor wafers remain in the same order after the polishing as before the polishing. There is also a carrier which is suitable for carrying out the process.

Abstract: A centrifuge for a semiconductor wafer has a centrifuge plate for holding a semiconductor wafer, has a drive for setting the centrifuge plate in rotation, and has a device for supplying a medium to a front side and a rear side of the semiconductor wafer. The centrifuge has a housing which separates a centrifuging area and the semiconductor wafer from the environment, and a device for generating a laminar gas flow in the housing. A method for centrifuging a semiconductor wafer has the semiconductor wafer being centrifuged in a laminar gas flow.

Abstract: A tool and method are provided for the abrasive machining of a substantially planar surface. The tool has a base body and a plurality of elements which are mounted on the base body and form a planar coating which is used as a working coating during machining of the surface.

Abstract: A method is provided for loading a heated susceptor or a susceptor segment of a deposition reactor with a substrate wafer which is resting on a holding means. Before making contact between the substrate wafer and the susceptor or susceptor segment, a holding position is reached in which the substrate wafer and the susceptor or susceptor segment are at a spaced vertical distance from one another. The substrate wafer is only brought into contact with the susceptor or the susceptor segment after a residence time in this holding position. There is also a device for loading a susceptor, in particular a susceptor segment of a deposition reactor.

Abstract: A process is for producing a semiconductor wafer with a front surface and a back surface, in which the semiconductor wafer is subjected to two-sided polishing. The process includes the following: (a) producing a hydrophobic surface on the semiconductor wafer by treating the semiconductor wafer with an aqueous HF solution; (b) simultaneous polishing of the front surface and the back surface of the semiconductor wafer with a surface which has been rendered hydrophobic, with an alkaline polishing abrasive being continuously supplied between two rotating upper and lower polishing plates, which are both covered with a polishing cloth, the pH of the polishing abrasive being from pH 8.5 to pH 12.5; (c) after an intended polishing abrasion has been reached, supplying a stopping agent to the semiconductor wafer; and (d) removing the semiconductor wafer from the polishing plates.

Abstract: A device for cleaning semiconductor wafers with a cleaning liquid, includes a cleaning station with a plurality of rotating pairs of rollers which are arranged one behind another and to which the cleaning liquid is applied. Each pair of rollers is formed by a top roller and a bottom roller, and the semiconductor wafer is conveyed between the pairs of rollers. There is also a conveyor means for conveying the semiconductor wafer to and from the cleaning station. The conveyor means has a film of conveyor liquid which is provided by the conveyor and on which the semiconductor wafer is conveyed. A supplying container provides the cleaning liquid to the top rollers in the form of a falling liquid which migrates over the rollers. There is also a method for cleaning semiconductor wafers in which such a device is used.

Abstract: A semiconductor wafer has a front side 1, a back side 2, a top layer 3, a bottom layer 4, an upper inner layer 5 lying beneath the top layer 3, an lower inner layer 6 lying above the bottom layer 4, a central region 7 between the layers 5 and 6, and an uneven distribution of crystal lattice defects. The crystal lattice defects are substitutionally or interstitially included nitrogen or vacancies.

Abstract: A method for cutting a multiplicity of disks from a hard brittle workpiece is by moving the workpiece at a defined feed rate through a wire web of a wire saw. In the method, the wire web is formed by a sawing wire which moves in a reciprocating manner and is covered with bonded abrasive grain. A cooling liquid is provided beneath the wire web, in which cooling liquid the sawing wire of the wire web is immersed when cutting off the disks. Also provided is a wire saw which is suitable for carrying out the method.

Abstract: There is an annular or internal-diameter saw and a method of protecting the clamping edge and of cleaning the saw blade of this annular or internal-diameter saw. The annular or internal-diameter saw has an element which partly screens the clamping edge and is arranged in the vicinity of the clamping edge and the saw blade, and has an outer material layer on the clamping edge. The outer material layer faces the element and is substantially harder than a clamping edge material lying behind it. The method is distinguished by the fact that workpiece residues thrown against the clamping edge are shattered when striking the clamping edge. This is due to the fact that an element partly screening the clamping edge is provided in the vicinity of the clamping edge and the saw blade.

Abstract: The nondestructive detection and characterization of crystal defects in monocrystalline semiconductor material is by a combination of photoluminescence heterodyne spectroscopy, photothermal heterodyne spectroscopy and SIRD.

Abstract: A rack-holding device with an attachment surface (1), which device has as least two side guides (2) and at least one stop (3), the stop (3) being arranged in each case in front of the at least two side guides (2), and the two side guides (2) being arranged parallel to and at a distance form one another. The two side guides (2) are designed in such a way that they have a bearing surface at essentially the same height. The two side guides (2) are each connected to the attachment surface (1). A sensor (7) is located on the attachment surface (1) and the sensor detects if a rack is in the position in the rack-holding device.

Abstract: A process for producing nitrogen-doped semiconductor wafers has the nitrogen being derived from a dopant gas which contains NH3. The process includes pulling a single crystal from a melt of molten semiconductor material, feeding the dopant gas to the semiconductor material, and cutting the nitrogen-doped semiconductor wafers off the pulled single crystal. The dopant gas is fed to the semiconductor material at most until pulling begins for that part of the single crystal from which the semiconductor wafers are cut.

Abstract: A method and a device for polishing disk shaped workpieces, has semiconductor wafers fixed on carrier plates, the carrier plates being pressed against a polishing plate, over which a polishing cloth is stretched, by means of polishing heads, and the polishing heads are accommodated in a polishing-plate superstructure. The carrier plates, following a polishing operation, are simultaneously lifted off the polishing plate by means of lifting devices in the polishing heads. The polishing-plate superstructure is displaced, together with the carrier plates, along a linear guide above a polishing line.

Abstract: The invention relates to a reproducible standard for calibrating and checking the bright-field channel of a surface inspection device used for examining the flat surface of a sample and to a method for producing said standard whereby a microstructure is produced on a surface of a substrate provided as a standard, characterized in that the microstructure is smoothed out.