Patent · US Expired

X-ray mask pellicle

US5793836A · kind A · utility

31Cited by
6References
12Claims
0Family size

Assignees

Inventors

Key dates

Filing dateSep 6, 1996
Grant dateAug 11, 1998
Priority date
Expiry dateSep 6, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70691
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An X-ray mask pellicle is capable of protecting the X-ray mask from contaminants and the wafer from contact with the X-ray absorber material of the mask. The X-ray mask pellicle is sufficiently thin to allow X-ray exposure at the required mask to wafer gaps yet is sufficiently durable, replaceable, tough and X-ray resistant to be used in X-ray lithography. A thin (organic or inorganic) X-ray mask pellicle to be placed covering the X-ray mask pattern area is fabricated as a thin film and attached to a support ring. A selected area of the pellicle film, tailored to cover the absorber pattern in the X-ray mask, is etched to decrease its thickness to below 2 .mu.m. If the thin film of the pellicle is not itself conductive, a thin conductive film may be coated on both sides. In an alternative embodiment, the separation between the pellicle and the X-ray mask can be achieved by forming the mask with a stepped profile.

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