Wacker-chemitronic Gesellschaft Fur Elektronik-grundstoffe Mbh

Franz Kohl

Anton Schnegg

Heinz Herzer

Helmut Zauhar

Franz Kuhn-Kuhnenfeld

Friedrich Nemetz

Karl Lener

Eberhard Mucke

Walter Hoch

Gerhard Zechmeister

Indium phosphide surfaces can be polished if, during the mechanical polishing operation, which is carried out in a customary manner, a component that yields free chlorine in an aqueous acidic medium, and, at the same time, a component that yields free carbon dioxide are applied to the surface to be polished.

Process for polishing indium phosphide surfaces

In the crucible-pulling of crystalline rods by the Czochralski technique, pulling plants that operate with a radiation screen offer a number of advantages. This process is optimized according to the invention by the use of a radiation screen which is joined to a lifting and pivoting mechanism that can be operated throughout the entire pulling process, and which is brought into position above the melt only when the contents of the crucible have been melted.

Process for the manufacture of high-purity monocrystals

The invention provides a process according to which the oxygen content in ucible-drawn silicon crystals can be lowered and kept substantially constant throughout the length of the rod. This is achieved in that, after applying the seed crystal to the melt pool, the silicon rod being drawn from the melt pool is initially rotated at a speed from 3 to 6 rev/min and this rotational speed is preferably increased to higher values during the drawing process.

Process for the production of high purity silicon monocrystals having a

A process for the crucible-free zone pulling of a polycrystalline rod held ertically, together with a seed crystal fixed at its lower end, in which a melting zone is produced by means of an induction heating coil surrounding the rod, which zone, by means of relative movement of the coil and rod, traverses the entire length of the rod starting from the seed crystal, characterized in that after attaching the seed crystal to the rod, a support member is moved, below the induction heating coil, towards the rod, which support member rests gently against the rod and after being positioned, solidifies to form a firm support for the rod. A device for carrying out the process is also included.

Crucible-free zone refining of semiconductor material including annular

Process for doping a semiconductor rod which comprises securing a semicontor rod containing a dopant and having a substantially smaller cross section than the rod to be doped against said rod, with the axes of the two rods substantially parallel to one another, both rods consisting of the same semiconductor material, fusing the two rods into a single rod and subjecting the rod so formed to a crucible zone melting process either subsequently or simultaneously.

Manufacture of doped semiconductor rods

Method for the production of dislocation-free, monocrystalline semiconduc rods with large diameters by crucible-free zone melting, which comprises producing the melting zone in a uniform electromagnetic field substantially symmetrical to the rod axis. The invention also relates to an induction heating coil for carrying out the method.

Growing community of inventors

Burghausen, Germany

Franz Kohl