Memc Electronic Materials, Inc.

Fabrizio Leoni

Robert J Falster

Marco Morganti

Marco Bricchetti

Luigi Vesco

Alessandro Corradi

Andrea Peratello

A process for removing copper from a boron doped, polished silicon wafer which contains copper on its polished surface and in its interior. In the process, the wafer is annealed at a temperature of at least about 75.degree. C. to increase the concentration of copper on the polished surface of the wafer and decrease the concentration of copper in the interior of the wafer. The polished surface of the annealed wafer is then cleaned to reduce the concentration of copper thereon. In addition, the annealing step is carried out at a temperature and a time such that the concentration of copper on the polished surface of the silicon will not increase by a factor of more than two upon storage of the annealed and cleaned wafer at room temperature for a period of 5 months.

Process for the removal of copper from polished boron doped silicon

An internal diameter saw, and in particular a method for operation which facilitates the maintenance of quality control of semiconductor wafers sliced from an ingot of source material. The internal diameter saw has a controller which monitors the deflection of the cutting edge of the blade at a location within the ingot as a wafer is sliced. Depending upon the deflection of the blade which is detected within the crystal, a blade dressing device is automatically activated to sharpen the blade following the cut.

Method and apparatus for automated quality control in wafer slicing

Wafer polishing apparatus includes a turntable having a polishing surface thereon, and a frame mounting the turntable for rotation relative to the frame about an axis. A pressure plate mounted by a spindle rotates about an axis spaced from the axis of rotation of the turntable, but is held from rotation about the axis of rotation of the turntable. The pressure plate is constructed for simultaneously holding multiple wafers with a polish face of the wafers facing the polishing surface of the turntable. The wafers are pressed against the polishing surface of the turntable by a cylinder which applies a force to the pressure plate. A floating head assembly operatively connecting the wafers to the pressure plate reorients the wafer relative to the pressure plate in response to pressure differentials over the polish face of the wafer engaging the polishing surface to substantially equalize the pressure distribution over the polish face of the wafer.

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Novara, Italy

Fabrizio Leoni