Method for spin coating a high viscosity liquid on a wafer
US6436851B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 2001 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Jan 5, 2021 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB05D1/005
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method for spin-coating a high viscosity liquid on a wafer surface capable of producing an improved uniformity in the coating thickness and a reduced material usage is disclosed. In the method, a liquid that has a high viscosity of at least 1000 cp is first provided. A wafer is then rotated to a speed of less than 300 rpm while simultaneously, a first volume of a high viscosity liquid is dispensed onto the wafer surface forming a cup-shaped pattern. The spinning of the wafer is then stopped and a second volume of the high viscosity liquid is dispensed into a cavity formed in the cup-shaped pattern to substantially fill the cavity. The wafer is then rotated again to a high rotational speed of at least 3000 rpm such that liquid in the cup-shaped pattern spreads out to substantially cover an entire surface of the wafer resulting in improved coating uniformity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.