Phase shift mask and phase shift mask blank
US5942356A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1997 |
| Grant date | Aug 24, 1999 |
| Priority date | — |
| Expiry date | Mar 27, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/32
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A half tone type phase shift mask as well as a phase shift mask blank for the mask is formed with a thin film light translucent portion made of essentially, nitrogen, metal, and silicon. The containing rate of each element and ratio in the thin film is specified in a certain range to improve film characteristics, such as acid resistance, photo resistance, conductivity, refractive index rate (film thickness), light transmission rate, etching selectivity, etc. of the light translucent portion. The phase shift mask satisfies optical characteristics (i.e., light transmitting rate and phase shift amount) with high precision, as well as reduces defects in the thin film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.