Abstract: A process for removal of impurities, in particular of dopants, from chlorosilanes which includes the following steps: (a) heating a deposition surface (3); (b) contacting the heated deposition surface (3) with at least one gaseous chlorosilane mixture, the gaseous chlorosilane mixture including at least one chlorosilane and at least one impurity, in particular at least one dopant; (c) at least partially removing the impurity, in particular the dopant, by forming polycrystalline silicon depositions on the deposition surface (3), the polycrystalline silicon depositions being enriched with the impurity, in particular with the dopant; (d) discharging the purified gaseous chlorosilane mixture; (e) contacting the heated deposition surface (3) with an etching gas to return the polycrystalline silicon depositions and the impurity, in particular the dopant, into the gas phase to form a gaseous etching gas mixture; and (f) discharging the gaseous etching gas mixture.

Abstract: A method for producing a wafer layer, including the method steps of: A) providing a carrier element; B) making the carrier element porous on at least one surface in order to produce a separating layer; C) applying a wafer layer to the separating layer of the carrier element by epitaxy; and D) detaching the wafer layer from the carrier element, with method steps B to D being repeated at least once, preferably multiple times, with the carrier element. The method step A includes the additional method steps of: A1) providing a carrier substrate; and A2) applying a seed layer to at least one surface and at least one lateral face of the carrier substrate by epitaxy in order to produce the carrier element. A carrier element for producing a wafer layer and an intermediate product are also provided.

Abstract: An apparatus for etching one side of a semiconductor layer of a workpiece, including at least one etching basin for receiving an electrolyte, a first electrode which is provided for electrically contacting the electrolyte located in the etching basin, a second electrode which is provided for electrically contacting the semiconductor layer, a electrical power source which is electrically conductively connected to the first and the second electrodes for generating an etching current, and a transport apparatus for transporting the workpiece relative to the etching basin such that a semiconductor layer etching face to be etched can be wetted by the electrolyte in the etching basin.

Abstract: An apparatus for etching one side of a semiconductor layer of a workpiece, including at least one etching basin for receiving an electrolyte, a first electrode which is provided for electrically contacting the electrolyte located in the etching basin, a second electrode which is provided for electrically contacting the semiconductor layer, a electrical power source which is electrically conductively connected to the first and the second electrodes for generating an etching current, and a transport apparatus for transporting the workpiece relative to the etching basin such that a semiconductor layer etching face to be etched can be wetted by the electrolyte in the etching basin.

Abstract: A process for removal of impurities, in particular of dopants, from chlorosilanes which includes the following steps: (a) heating a deposition surface (3); (b) contacting the heated deposition surface (3) with at least one gaseous chlorosilane mixture, the gaseous chlorosilane mixture including at least one chlorosilane and at least one impurity, in particular at least one dopant; (c) at least partially removing the impurity, in particular the dopant, by forming polycrystalline silicon depositions on the deposition surface (3), the polycrystalline silicon depositions being enriched with the impurity, in particular with the dopant; (d) discharging the purified gaseous chlorosilane mixture; (e) contacting the heated deposition surface (3) with an etching gas to return the polycrystalline silicon depositions and the impurity, in particular the dopant, into the gas phase to form a gaseous etching gas mixture; and (f) discharging the gaseous etching gas mixture.