Siltronic AG | Date: 2015-11-03
A cleaning method involves: disposing in a cleaning liquid held in a cleaning tank an object to be cleaned; and ultrasonically vibrating the cleaning liquid via an intermediate medium in contact with the cleaning tank to clean said object, the ultrasonically vibrating involving: ultrasonically vibrating the cleaning liquid with the cleaning liquid and the intermediate medium allowing sonic velocities, respectively, having a first difference; and ultrasonically vibrating the cleaning liquid with the cleaning liquid and the intermediate medium allowing sonic velocities, respectively, having a second difference different from the first difference
Siltronic AG | Date: 2015-11-05
The invention relates to a semiconductor wafer of monocrystalline silicon, and to a method for producing it. The semiconductor wafer has a zone, DZ, which is free of BMD defects and extends from a front side of the semiconductor wafer into the bulk of the semiconductor wafer, and a region having BMD defects which extends from the DZ further into the bulk of the semiconductor wafer. A silicon single crystal is pulled by the Czochralski method and processed to form a polished monocrystalline silicon substrate wafer. The substrate wafer is treated by rapidly heating and cooling the substrate wafer, slowly heating the rapidly heated and cooled substrate wafer, and keeping the substrate wafer at a specific temperature and over a specific period.
Siltronic AG | Date: 2015-03-26
A method for slicing wafers from a workpiece using a sawing wire, wherein at least two wire guide rolls clamp a wire web, each wire guide roll having a multiplicity of grooves in its lateral surface, wherein at least one groove in which no wire is inserted during the wire sawing is present alongside a wire-guiding groove and, after wear on the wire-guiding grooves or after a defined number of sawing processes, the sawing wire is wound over into the previously unoccupied grooves that are not yet worn or used, respectively.
Siltronic AG | Date: 2015-07-30
A growing single crystal is supported in the region of a conical section of the single crystal via a supporting body during crystallization of the single crystal by the FZ method. The method comprises pressing the supporting body against the conical section of the growing single crystal at a temperature at which a first material of the supporting body becomes soft, and continuing pressing the supporting body against the conical section of the growing single crystal until the first material and a second material of the supporting body that remains hard at the cited temperature touch the conical section of the growing single crystal.
Siltronic AG | Date: 2015-04-02
A method for drying wafer substrates immersed into a liquid, and wafer holder for conduction of the method. The method involves holding substrates on a wedge-shaped edge of an elongated wafer holder, the substrates being upright on the wafer holder; transferring the substrates and the wedge-shaped edge of the wafer holder from the liquid to a gas space with a vapor which does not condense on the substrates and which lowers surface tension of liquid residues adhering to the substrates, wherein the removal of liquid residues between the wafer substrates and the wafer holder through a slot in the middle of the wedge-shaped edge of the wafer holder.