Patent · US Expired

Vacuum assisted debris removal system

US5973764A · kind A · utility

18Cited by
6References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 19, 1997
Grant dateOct 26, 1999
Priority date
Expiry dateJun 19, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70866
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A vacuum manifold having a rectangular opening with vacuum access bores connected into the rectangular opening for an illumination field to be projected there through. A vacuum manifold is placed between a photosensitive resist covered wafer and a lens element in a photolithographic tool. The relatively high illumination energy in an illumination field used for projecting an image of a reticle onto a photosensitive resist covered wafer often results in ablated, evaporated, and effused material being coated on the lens element. The vacuum manifold placed between the lens element and the photosensitive resist covered wafer creates an airflow for removing debris or contamination preventing coating of the lens surface. This prevents image quality from degradation over time, as well as reduces downtime needed for cleaning or maintenance of the photolithographic tool.

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