Patent · US Expired

Crucible-free zone refining of semiconductor material including annular support member

US4140571A · kind A · utility

3Cited by

4References

5Claims

0Family size

Assignee

Wacker-Chemitronic Gesellschaft fur Elektronik Grundstoffe mbH · DE

Inventors

Heinz Herzer · Burghausen, DE
Helmut Zauhar
Eberhard Mucke · Schweich, DE
Franz Kohl · Burghausen, DE

Key dates

Filing date	Oct 11, 1977
Grant date	Feb 20, 1979
Priority date	—
Expiry date	Oct 11, 1997

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T117/1084
WIPO fieldSurface technology, coating
WIPO sectorChemistry

Abstract

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.