Methods and compositions for imaging acids in chemically amplified photoresists using pH-dependent fluorophores
US6376149B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | May 26, 1999 |
| Grant date | Apr 23, 2002 |
| Priority date | — |
| Expiry date | May 26, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/105
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of imaging acids in chemically amplified photoresists involves exposing to radiation a chemically amplified photoresist comprising a pH-dependent fluorophore. Upon exposure to radiation, such as deep-UV radiation, the chemically amplified photoresist produces an acid, which is then visualized by the fluorescence of the pH-dependent fluorophore. An image is generated from the fluorescence of the pH-dependent fluorophore, thus providing a map of the location of the acid in the photoresist. The images are able to be visualized prior to a post-exposure bake of the resist composition. Chemically amplified photoresists comprising pH-dependent fluorophores are useful in the practice of the present invention. The method finds particular use in examining the efficiency of photoacid generators in chemically amplified photoresists, in that it allows the practitioner the ability to directly determine the amount of acid generated within the photoresist.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.