Patent · US Expired

Contoured inner after-heater shield for reducing stress in growing crystalline bodies

US5558712A · kind A · utility

13Cited by
4References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 4, 1994
Grant dateSep 24, 1996
Priority date
Expiry dateNov 4, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T117/1036
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

An apparatus for growing hollow crystalline bodies by the EFG process, comprising an EFG die having a top surface shaped for growing a hollow crystalline body having a cross-sectional configuration in the shape of a polygon having n faces, and a radiation shield adjacent to and surrounded by the top end surface of the die, characterized in that the shield has an inner edge defining a similar polygon with n sides, and the inner edge of the shield is notched so that the spacing between the n faces and the n sides is greatest between the central portions of the n faces and the n sides, whereby the greater spacing at the central portions helps to reduce lateral temperature gradients in the crystalline body that is grown by use of the die.

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