Prevention of photoresist scumming
US7175944B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 2004 |
| Grant date | Feb 13, 2007 |
| Priority date | — |
| Expiry date | Oct 24, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/091
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A photo acid generator (PAG) or an acid is used to reduce resist scumming and footing. Diffusion of acid from photoresist into neighbors causes a decreased acid level, and thus causes resist scumming. An increased acid layer beneath the resist prevents acid diffusion. In one embodiment, the increased acid layer is a layer of spun-on acid or PAG dissolved in aqueous solution. In another embodiment, the increased acid layer is a hard mask material with a PAG or an acid mixed into the material. The high acid content inhibits the diffusion of acid from the photoresist into neighboring layers, and thus substantially reduces photoresist scumming and footing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.