Method for manufacturing a phase shift photomask
US6511777B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 21, 2000 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Oct 7, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/26
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for fabricating a phase shift photomask (10) includes providing a photomask (12) having a substantially opaque layer (16) on a surface (14) of a substantially transparent substrate (18). The opaque layer (14) includes a removed portion to define a light transmitting pattern (20) of the photomask (12). The method also includes depositing an implant (22) in a portion of the substrate (18). The implanted portion (24) of the substrate (18) includes an etch rate different than an etch rate of an unimplanted portion (32) of the substrate (18). The method includes initiating an etch of the substrate (18) corresponding to the light transmitting pattern (20) and monitoring a rate of the etch. The method further includes terminating the etch in response to detecting a change in the rate of the etch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.