×

Semiconductor wafer chuck with built-in standoff for contactless photolithography

  • US 4,006,909 A
  • Filed: 04/16/1975
  • Issued: 02/08/1977
  • Est. Priority Date: 04/16/1975
  • Status: Expired due to Term
First Claim
Patent Images

1. A semiconductor wafer vacuum chuck for providing a controlled separation between a surface of a semiconductor wafer having a small degree of flexibility and a photographic mask overlying said surface upon the application of a vacuum to said chuck comprising:

  • an element including at least one substantially planar surface for receiving said wafer thereon, said element having means to allow a vacuum to be applied to said planar surface, andmeans disposed on said surface of said element for mechanically maintaining a fixed distance between a peripheral portion of said wafer supported on said means and said surface of said element, said means being made of non-resilient material and extending no more than about 0.1 millimeters above said surface, and positioned in a pattern to allow a central portion of said wafer spaced inwardly from said means to be drawn towards said surface of said element upon the application of said vacuum to said surface of said element.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×