Siltronic Ag

Alexander Heilmaier

Anton Huber

Klaus Roettger

Leszek Mistur

Guido Wenski

Thomas Altmann

Gerhard Heier

Robert Weiss

Vladimir Dutschke

Makoto Tabata

Torsten Olbrich

Helmut Seehofer

Johannes Staudhammer

Robert Drexler

Rainer Baumann

Clemens Radspieler

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

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.

Method for producing a semiconductor wafer

Slicing multiple cylindrical workpieces into wafers by a multi wire saw with a gang length L, is performed by: and making right-hand side of the inequality as large as possible, where Lwith i=1 . . . n are for the lengths of the workpieces and Ais a predefined minimum spacing, is satisfied,

Method for simultaneously slicing at least two cylindrical workpieces into a multiplicity of wafers

The invention relates to a method for removing material from a semiconductor wafer by machining, in which a semiconductor wafer held on a wafer holder and a grinding wheel lying opposite it are rotated independently of one another, the grinding wheel being arranged laterally offset with respect to the semiconductor wafer and being positioned in such a way that an axial center of the semiconductor wafer passes into a working range of the grinding wheel, the grinding wheel being moved in the direction of the semiconductor wafer at an infeed rate, with the result that grinding wheel and semiconductor wafer are advanced toward one another while the semiconductor wafer and grinding wheel are rotating about parallel axes, so that a surface of the semiconductor wafer is ground, with the grinding wheel being moved back at a return rate after a defined amount of material has been removed, wherein the grinding wheel and semiconductor wafer are advanced toward one another by a distance of 0.03&#x2013;0.5 &#x3bc;m during one revolution of the semiconductor wafer.

Method for removing material from a semiconductor wafer

A silicon semiconductor wafer with a diameter of greater than or equal to 200 mm and a polished front surface and a polished back surface and a maximum local flatness value SFQRof less than or equal to 0.13 &#x3bc;m, based on a surface grid of segments with a size of 26 mm&#xd7;8 mm on the front surface, wherein the maximum local height deviation P/V(10&#xd7;10)of the front surface from an ideal plane is less than or equal to 70 nm, based on sliding subregions with dimensions of 10 mm&#xd7;10 mm. There is also a process for producing a multiplicity of silicon semiconductor wafers by simultaneous double-side polishing between in each case one lower polishing plate and one upper polishing plate, which rotate, are parallel to one another and to which polishing cloth has been adhesively bonded, while a polishing agent, which contains abrasives or colloids, is being supplied, with at least 2 &#x3bc;m of silicon being removed, wherein a predetermined proportion of the semiconductor wafers is at least partially polished using a lower polishing pressure, and a further proportion of the semiconductor wafers is polished using a higher polishing pressure.

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Haiming, Germany

Alexander Heilmaier