Method for laser interference lithography using diffraction grating
US8399184B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 2008 |
| Grant date | Mar 19, 2013 |
| Priority date | — |
| Expiry date | Sep 21, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/1814
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for laser interference lithography using a diffraction grating includes (a) forming a photoresist layer on a work substrate to which a repeated fine pattern is to be formed; (b) forming a refractive index matching material layer on the photoresist layer; (c) forming on the refractive index matching material layer a diffraction grating layer having a period of diffraction grating within the range from λ/ng to λ/n0 (λ is a wavelength of laser beam, ng is a refractive index of the diffraction grating, and n0 is a refractive index in the air or in vacuum); and (d) exposing the photoresist layer by means of mutual interference of positive and negative diffracted lights with the same absolute value by inputting a laser beam perpendicularly to the diffraction grating layer. This method allows to realize an interference pattern with higher resolution and to use a laser source with lower coherence.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.