Other

Andreas Ehlert

Wilfried Von Ammon

Michael Kerstan

Erich Dornberger

Laszlo Fabry

Anton Schnegg

Holger Lundt

Dieter Helmreich

Gabriele Lechner

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. There is also a carrier for the double-side polishing of at least one semiconductor wafer, having a cutout for holding the semiconductor wafer which is lined with a shaped part made from plastic. The shaped part is constructed in such a manner that it divides a free space between an edge of the semiconductor wafer and the carrier into a plurality of separate empty spaces.

Process for producing a semiconductor wafer

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.

Method and device for nondestructive detection of crystal defects

A method for pulling a single crystal has a monocrystalline seed crystal being brought into contact with molten material and an interface being formed between solid and molten material, and molten material being caused to solidify with the formation of a thin-necked crystal and a cylindrical single crystal. The method is one wherein, during the pulling of the thin-necked crystal, it is ensured that the ratio V/G(r) is above a constant C,having the value 1.3*10,cm,/Kmin, with V being the pulling rate, with G(r) being the axial temperature gradient at the interface and r being the radial distance from the center of the thin-necked crystal.

Method for pulling a single crystal

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Mehring, Germany

Andreas Ehlert