Apparatus and method for uniformly coating a substrate in an evacuable chamber
US5229171A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1991 |
| Grant date | Jul 20, 1993 |
| Priority date | — |
| Expiry date | Dec 23, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/136
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An apparatus and method including a droplet coating generator for generating a stream of electrically charged coating droplets within an evacuable chamber towards a substrate positioned within the evacuable chamber. A piezoelectric vibrator and orifice plate coupled thereto generate the stream of coating droplets. The coating droplets are urged to move in a sweeping motion across the substrate by at least one pair of opposing spaced apart electrodes powered by an electrical power supply. A uniform coating is thus produced while the evacuable chamber is maintained at subatmospheric pressure as required during typical semiconductor processing. Multiple applications of a photoresist coating may be applied by the coating apparatus without requiring that the evacuable chamber be repeatedly vented and pumped down to subatmospheric pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.