Patent · US Expired

Method for forming photoresist patterns

US5858590A · kind A · utility

2Cited by
2References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 24, 1997
Grant dateJan 12, 1999
Priority date
Expiry dateOct 24, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03F7/20
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method for forming photoresist patterns by performing a photolithograpy process by the unit of a predetermined number of wafers, wherein the photoresist patterns are formed under a condition that an exposure time taken to fore each of the photoresist patterns is predetermined taking into consideration a variation in reflection factor, on the basis of the following equation: EQU Z=X+{(r-a).times.(Y-X)/(.beta.-.alpha.)} where, "T" represents a reference thickness corresponding to a thickness of a photoresist film to be patterned to form a corresponding one of the photoresist patterns, exhibiting a minimum reference factor or a maximum reference factor, "T'" a thickness limit more than the reference thickness (T), ".alpha." a reference reflection factor at the reference thickness (T), ".beta." a reflection factor limit at the thickness limit (T'), "r" a varied reflection factor, "X" a reference exposure time at the reference reflection factor (.alpha.), "Y" an exposure time limit at the reflection factor limit (.beta.), and "Z" the varied exposure time.

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