Patent · US Expired

Method of producing an optical element having a multiple-level step-like structure through lithography

US6562253B1 · kind B1 · utility

5Cited by
2References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 28, 2000
Grant dateMay 13, 2003
Priority date
Expiry dateJul 28, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B5/1857
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A method of producing an optical element having a multiple-level step-like structure includes a first process for providing a first mask pattern at a position corresponding to a predetermined boundary among boundaries at steps of the multiple-level step-like structure of a substrate, the first mask pattern having a width narrower than that of a single step, a second process for providing a second mask pattern upon the substrate having the first mask pattern formed thereon, the second mask pattern having a width corresponding to a single step or plural steps of the multiple-level step-like structure and a third process for processing the substrate by use of the first and second mask patterns and thereafter for removing the second mask pattern while leaving the first mask pattern there. After repeating the second and third processes plural times of a predetermined number, the first mask pattern is removed.

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