Patent · US Expired

Substrate support shield in wafer processing reactors

US5855687A · kind A · utility

318Cited by
22References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 20, 1994
Grant dateJan 5, 1999
Priority date
Expiry dateOct 20, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/68735
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

Apparatus for CVD processing wherein a wafer mounted on a vertically movable susceptor beneath a showerhead. The susceptor extends beyond the outer perimeter of the wafer such that, when the susceptor is raised into contact with a shield ring which normally rests on a ring support in the chamber, the shield ring engages outer portion of the susceptor beyond the perimeter of the wafer, lifting the shield ring off its support. The shield ring shields the edge of the top surface of the susceptor during the deposition, whereby unwanted deposition on the susceptor is prevented while, at the same time, allowing for deposition over the entire upper surface of the wafer. To center the shield ring and the susceptor with respect to each other, the shield ring may include a plurality of centering protrusions, at least some of which engage the susceptor as it moves upwards to lift the shield ring off its supports in the chamber.

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