Liquid immersion heating process for substrate temperature uniformity
US5716763A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 6, 1994 |
| Grant date | Feb 10, 1998 |
| Priority date | — |
| Expiry date | Dec 6, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/168
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A temperature-sensitive film such as a resist is baked onto a semiconductor substrate such as a mask blank by immersion in a heated liquid. A barrier coating may optionally be applied to the substrate prior to immersion and later removed. The substrate is subsequently cooled by immersing the substrate in a cooling liquid or dissolving the heated liquid from the substrate with a rinsing liquid at a temperature sufficiently lower than that of the heated liquid. Temperature uniformity within .+-.0.2.degree. C. is thereby achieved across the regions of varying thickness in the silicon wafer and membrane. Where a resist has been deposited on the mask blank substrate, heating and cooling by immersion results in improved line size control after exposure and development down to 0.25 .mu.m.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.