Patent · US Expired

Multi mask method for selective mask feature enhancement

US5563012A · kind A · utility

65Cited by
5References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 30, 1994
Grant dateOct 8, 1996
Priority date
Expiry dateJun 30, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/70466
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The preferred embodiment of the present invention is a method of enhancing normally unenhanced features types. Pattern shapes are placed on two or more relatively simple, modified masks instead of using a single mask containing diverse feature types. On these modified masks, (hereinafter "overlay masks"), all of the features are the type normally enhanced. A composite pattern is printed into photoresist through successive exposure to the overlay masks.

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