Siltronic Ag

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Wacker Siltronic Gesellschaft Fur Halbleitermaterialien Ag

Wacker Siltronic Gesellschaft F&uuml;r Halbleiter Materialien Ag

Wacker Siltronic Gesellschaft F{dot Over (u)}r Halbleitermaterialien Ag

Gerhard Heier

Guido Wenski

Thomas Altmann

Wolfgang Winkler

Ernst Feuchtinger

Willibald Bernwinkler

Thomas Buschhardt

Klaus Roettger

Alexander Heilmaier

Wolfgang Siebert

Klaus Messmann

Johann Glas

Gunther Kann

Ruediger Schmolke

Martin Fürfanger

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

A semiconductor wafer is guided in a cutout in a carrier while a thickness of the semiconductor wafer is reduced to a target thickness by material removal from the front and back surfaces simultaneously. The semiconductor wafer is machined until it is thinner than a carrier body and thicker than an inlay used to line the cutout in the carrier to protect the semiconductor wafer. The carrier is distinguished by the fact that the carrier body and the inlay have different thicknesses throughout the entire duration of the machining of the semiconductor wafer, the carrier body being thicker than the inlay, by from 20 to 70 &#x3bc;m. Themethod provides semiconductor wafers polished on both sides, having a front surface, a back surface and an edge, and a local flatness of the front surface, SFQRof less than 50 nm with an edge exclusion of R-2 mm and less than nm with an edge exclusion of R-1 mm, based on a site area of 26 by 8 mm.

Method for machining a semiconductor wafer on both sides in a carrier, carrier, and a semiconductor wafer produced by the method

A semiconductor wafer with a front surface and a back surface and an epitaxial layer of semiconducting material deposited on the front surface. In the semiconductor wafer, the epitaxial layer has a maximum local flatness value SFQRof less than or equal to 0.13 &#x3bc;m and a maximum density of 0.14 scattered light centers per cm. The front surface of the semiconductor wafer, prior to the deposition of the epitaxial layer, has a surface roughness of 0.05 to 0.29 nm RMS, measured by AFM on a 1 &#x3bc;m&#xd7;1 &#x3bc;m reference area. Furthermore, there is a process for producing the semiconductor wafer. The process includes the following process steps: (a) as a single polishing step, simultaneous polishing of the front surface and of the back surface of the semiconductor wafer between rotating polishing plates while an alkaline polishing slurry is being supplied, the semiconductor wafer lying in a cutout of a carrier whose thickness is dimensioned to be 2 to 20 &#x3bc;m less than the thickness of the semiconductor wafer after the latter has been polished; (b) simultaneous treatment of the front surface and of the back surface of the semiconductor wafer between rotating polishing plates while a liquid containing at least one polyhydric alcohol having 2 to 6 carbon atoms is being supplied; (c) cleaning and drying of the semiconductor wafer; and (d) deposition of the epitaxial layer on the front surface of the semiconductor wafer produced in accordance with steps (a) to (c).

Epitaxially coated semiconductor wafer and process for producing it

A process is for material-removing machining, on both sides simultaneously, of semiconductor wafers having a front surface and a back surface, the semiconductor wafers resting in carriers which are set in rotation by means of an annular outer drive ring and an annular inner drive ring and being moved between two oppositely rotating working disks in a manner which can be described by means of in each case one path curve relative to the upper working disk and one path curve relative to the lower working disk, wherein the two path curves after six loops around the center have the appearance of still being open, and at each point have a radius of curvature which is at least as great as the radius of the inner drive ring.

Process for material-removing machining of both sides of semiconductor wafers

Double-side polishing process with reduced scratch rate and device for carrying out the process

A semiconductor wafer has a front surface and a back surface and flatness values based on partial areas of a surface grid on the front surface of the semiconductor wafer, which has a maximum local flatness value SFQR of less than or equal to 0.13 &mgr;m and individual SFQR values which in a peripheral area of the semiconductor wafer do not differ significantly from those in a central area of the semiconductor wafer. There is also a process for producing this semiconductor wafer, wherein the starting thickness of the semiconductor wafer is 20 to 200 &mgr;m greater than the thickness of the carrier and the semiconductor wafer is polished until the end thickness of the semiconductor wafer is 2 to 20 &mgr;m greater than the thickness of the carrier.

Semiconductor wafer with improved flatness, and process for producing the semiconductor wafer

A process for the double-side polishing of semiconductor wafers between two polishing plates which rotate in opposite directions and are covered with polishing cloth, so that at least 2 &mgr;m of semiconductor material is removed. The semiconductor wafers lay in plastic-lined cutouts in a set of a plurality of planar carriers which are made from steel and the mean thickness of which is 2 to 20 &mgr;m smaller than the mean thickness of the fully polished semiconductor wafers. The set comprises only those carriers whose difference in thickness is at most 5 &mgr;m, and each carrier belonging to the set has at least one unambiguous identification feature which assigns it to the set. An item of information contained in the identification feature is used in order for the plastic linings to be exchanged at fixed intervals and to ensure that the semiconductor wafers remain in the same order after the polishing as before the polishing. There is also a carrier which is suitable for carrying out the process.

Process for the double-side polishing of semiconductor wafers and carrier for carrying out the process

Growing community of inventors

Burghausen, Germany

Gerhard Heier