Wacker-chemitronic Gesellschaft Fur Elektronik-grundstoffe Mbh

Heliotronic Forschungs- Und Entwicklungsgesellschaft Fur

Wacker-chemitronic Fur Elektronic Grundstoffe Mbh

Alfred Moritz

Dieter Regler

Dieter Seifert

Klemens Muhlbauer

Walter Berger

Bruno Meissner

August Freudlsperger

Volker Ofenmacher

Erhard Sitrl

A process and an apparatus for carrying out a process for multiple lap cutting of solid materials, especially those having rectangular or square cross sections, in which the workpiece is subjected, during the cutting operation, to a rotating motion thereby improving the quality of the discs and increasing the cutting efficiency.

Process and apparatus for multiple lap cutting of solid materials

An apparatus and process for cementing semiconductor discs onto a carrier ate, wherein after the carrier plate is coated with a layer of adhesive substance, the discs are applied to the adhesive layer and a vacuum-tight sealing dome is placed over the carrier plate to define a sealed, hollow space. A chemically-inert elastic diaphragm is clamped within the dome 0.2 to 1.5 mm above the free surface of the discs, to divide the hollow space into two sections or subchambers which are initially simulataneously evacuated. Then, air pressure is applied to the upper section, so that the discs are pressed by the diaphragm onto the cement layer. Air pressure is then subsequently fed to the lower hollow space, so that the dome can be removed from the carrier plate.

Process for cementing semiconductor discs onto a carrier plate

A lap cutting abrasive for use with lap cutting blades, comprising one part y weight of a low viscosity carrier liquid, and one to three parts by weight of cutting particles having an average size of from 10 to 50 .mu.m suspended in the carrier liquid. The carrier liquid has a viscosity of from 1 to 10 cP, and preferably is aqueous glycerin. The cutting particles preferably have an average particle size of from 15 to 30 .mu.m. In a further embodiment, the average particle size of the cutting particles is matched to the thickness of the lap cutting blade used during sawing. Preferably, the cutting particles have an average particle size corresponding to 0.15 to 0.1 times the thickness of the lap cutting blade used during sawing.

Lap cutting abrasive

Apparatus for machining workpieces by abrasion by means of an oscillating ltiple-blade tool, which is moved across the workpiece. The moved masses define an oscillatory system, as a result of which the energy can be stored in the reversal ranges by a buffer system. This apparatus, especially when designed as a lap-cutting machine for cutting semiconductor rods, is preferably driven by the oscillation of the masses to be moved, and is driven in the resonance range. The tool carriages are buffer loaded at each end and are oscillated at or near the natural resonance frequency of the moving masses.

Apparatus for machining workpieces by abrasion

A process for the multiple lap cutting of solid materials, using a set of parallel, spaced apart blades mounted on the frame of a gang-saw for reciprocal movement over the solid materials to be cut, in a suspension of a lapping abrasive, wherein a pressure of from 100 to 1,000 gf per blade is exerted on the solid material, the free working length of the blades is held between 110 to 250 mm, and wherein the pressure applied to the blades is inversely proportional to the length of the blades, and the blades move through the solid material at a mean lateral speed of from 30 to 150 meters per minute.

Process for multiple lap cutting of solid materials

Lap cutting blades are provided which are useable for the multiple lap cung of solid materials, such as semiconductorrods. The blades each have a generally rectilinear cutting edge, the length of which is 1-75 times the thickness of the blade, as measured at its cutting edge. The cutting edge of each blade has rectilinear edge portions separated by a plurality of notched edge portions which, in turn, define a plurality of recesses which encompass 5 to 25% of the total blade length and 5 to 40% of the effective operating length of the blade. The notched blade edge portions define a notch angle of between 20 and 80 degrees, as measured between the tangent thereto at its point of intersection with the rectilinear cutting edge portion and a line perpendicular to the rectilinear cutting edge portion.

Growing community of inventors

Burghausen, Germany

Alfred Moritz