Patent · US Expired

Boat for heat treatment

US5820367A · kind A · utility

34Cited by
5References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 18, 1996
Grant dateOct 13, 1998
Priority date
Expiry dateSep 18, 2016

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC30B25/12
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

Support members are provided in a vertically spaced relation on a plurality of upright columns. A wafer support member comprises a projection formed to be annular along an inner peripheral edge of a ring and an outer wall formed along an outer peripheral edge thereof. The wafer is positively supported at a position inwardly of the outer peripheral edge thereof by the projection of the wafer support member despite the presence or absence of a warp thereof. Therefore, a load caused by the weight of the wafer is dispersed over the entire projection of the wafer support member. This suppresses the concentration of stress on a specific portion of the wafer support portion, and a surface defect called a slip generated when the wafer is heat treated can be eliminated.

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