Patent · US Expired

Apparatus for zone refining

US4201746A · kind A · utility

7Cited by
7References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 13, 1977
Grant dateMay 6, 1980
Priority date
Expiry dateJun 13, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T117/1088
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

Improvements in apparatus for zone refining polycrystalline semiconductor rods to produce monocrystalline semiconductor rods are disclosed. In the apparatus, an inductive heating chamber is employed which has a longitudinal dimension independent of the length of the polycrystalline semiconductor rod to be processed. The longitudinal dimension of the induction heating chamber is limited only by considerations of the space required for the RF induction heating coil and related apparatus which must be mounted within the chamber, the viewing space required for the operator to observe the zone refining process, and the heating effect on the structures above and below the chamber. First and second gas tight bellows are provided which, respectively, surround the rod holder and the seed holder. One end of each of the first and second bellows is releasably and sealingly attached to the induction heating chamber, while the other end of each of the first and second bellows is attached to the base of the rod holder or seed holder, respectively. The base of the rod holder or seed holder incorporates a gas tight magnetic fluid seal means for providing dynamic sealant between the chamber and driv…

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