Photolithography mask and method of fabrication
US5795684A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 5, 1996 |
| Grant date | Aug 18, 1998 |
| Priority date | — |
| Expiry date | Apr 5, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/50
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A novel mask for photolithography in semiconductor processing and fabrication method is disclosed. The mask includes a layer of transmissive material transparent to the wavelength of light to be used deposited thereon. The transmissive material is plasma etched in accordance with a pattern in photoresist deposited thereon to create trench portions in the transmissive material. A layer of absorbing material absorptive to the wavelength of light to be used is deposited within the trench portions. The surface of the mask is then planarized to create a substantially smooth mask layer having trench portions in the transmissive material and absorbing layer portions within the trench portions. If desired, a second layer of transmissive material can be deposited over the smooth mask layer to provide a protective cap to create an overall smooth, flat completed mask surface. The mask is useful for transmissive photolithography applications as well as reflective photolithography applications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.