Patent · US Expired

Step mask

US6472766B2 · kind B2 · utility

9Cited by
12References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 5, 2001
Grant dateOct 29, 2002
Priority date
Expiry dateJan 5, 2021

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F1/44
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A step mask having a plurality of test cells and a method for producing the same. Each test cell of the step mask is etched for a different amount of time and therefore has a different etch depth or height. The number of phase shifter layer etch iterations can be conducted on a column-by-column and row-by-row basis to decrease the number of etch iterations.

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