Siltronic Ag

Klaus Roettger

Alexander Heilmaier

Leszek Mistur

Makoto Tabata

Clemens Zapilko

Thomas Jaeschke

Gerhard Heier

Vladimir Dutschke

Andreas Muehe

Johannes Staudhammer

Torsten Olbrich

Herbert Becker

Rainer Baumann

A monocrystalline semiconductor wafers have an average roughness Rof at most 0.8 nm at a limiting wavelength of 250 &#x3bc;m, and an ESFQRof 8 nm or less given an edge exclusion of 1 mm. The wafers are advantageously produced by a method comprising the following steps in the indicated order:

Monocrystalline semiconductor wafer and method for producing a semiconductor wafer

A method for polishing at least one wafer composed of semiconductor material that has a front side and the rear side includes performing at least one first polishing step including simultaneously polishing both front and rear sides of the at least one wafer at a process temperature between an upper polishing plate and a lower polishing plate. Each of the upper polishing and lower polishing plates is covered with a polishing pad having an inner edge and an outer edge, a hardness of at least 80&#xb0; Shore A, a compressibility of less than 2.5%, and respective upper and lower surfaces that come into contact with the wafer being polished. The upper and lower surfaces form a polishing gap extending from the inner edge to the outer edge. A height of the polishing gap at the inner edge differs linearly from the height of the polishing gap at the outer edge.

Method for polishing a semiconductor wafer

A method of polishing a semiconductor wafer includes simultaneous double-side polishing the wafer in a gap of a polishing device between a lower polishing plate covered with a lower polishing pad and upper polishing plate covered with an upper polishing pad while supplying a polishing agent. A first of the upper and lower polishing pads is dressed using a dressing tool. The dressing tool is mounted in the gap so that it extends from the inner edge to the outer edge of the first polishing pad. The distance between the dressing tool and a second of the upper and lower polishing pads at the inner edge of the second polishing pad differs from a corresponding distance at the outer edge of the second polishing pad. After the dressing, the at least one semiconductor wafer in the gap is polished.

Method for polishing semiconductor wafers by means of simultaneous double-side polishing

Semiconductor wafers are CMP polished by polishing the rear side of the semiconductor wafer by means of CMP with a material removal with a profile along the diameter of the wafer wherein material removal is higher at the center than at the edge of the rear side; and polishing the front side of the wafer by means of CMP with a material removal with a profile along the diameter of the wafer wherein material removal is lower in the center of the front side than in an edge region of the front side.

A method for producing a semiconductor wafer. The method includes placing the semiconductor wafer in a cutout in a carrier. Both sides of the semiconductor wafer are polished between an upper and a lower polishing plate with a polishing agent until the thickness of the center of the semiconductor wafer is less than the thickness of the carrier and from 10 &#x3bc;m to 30 &#x3bc;m of semiconductor wafer material is removed. The polishing agent contains 0.1 to 0.4% by weight of SiOand 0.1 to 0.9% by weight of an alkaline component.

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Bachmehring, Germany

Klaus Roettger