Method of forming a retrograde photoresist profile
US5221596A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 3, 1991 |
| Grant date | Jun 22, 1993 |
| Priority date | — |
| Expiry date | Sep 3, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/0758
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A retrograde profile is formed in a photoresist layer (11, 20) by modifying the rate at which a photoresist developer solution dissolves a portion (12) of a photoresist layer (11, 20). The photoresist layer (11, 20) is exposed to a chemical such as hexamethyldisilizane or dimethylsulfoxane to allow a portion (12) of the photoresist (11, 20) to absorb the chemical. The photoresist (11, 20) is then heated in order to enhance a reaction between the photoresist (11, 20) and the chemical. The reaction modifies a portion (12) of the photoresist (11, 20) to reduce the rate at which the portion (12) of the photoresist (11, 20) is dissolved by a developer solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.