Method for removing chemical residues from a surface
US6036785A · kind A · utility
Inventor
Key dates
| Filing date | May 2, 1997 |
| Grant date | Mar 14, 2000 |
| Priority date | — |
| Expiry date | May 2, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67051
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Method [and apparatus ] for quickly and controllably removing chemical residues and particle accumulations from an exposed surface of an object. A slurry, containing a slurry liquid and containing small scrubber particles that optionally have a range of at least two distinct particle sizes, is directed at the exposed surface to remove most or all of the residues and accumulations from the exposed surface. The slurry flow may be pulsed or be relatively constant. The exposed surface of the object is then partly or fully submerged in a rinse liquid that includes a strong base and/or a strong oxidizing agent. The rinse liquid is subjected to ultrasonic wave motion with a chosen wave displacement direction, and the ultrasonic waves have one or more distinct wavelengths, chosen to cover a range of expected sizes of chemical residues, particle accumulations and/or scrubber particles to be removed. Optionally, the ultrasonic wave displacement direction is chosen approximately parallel to an exposed surface from which residues, accumulations and/or scrubber particles are to be removed. Optionally, the ultrasonic wavelength(s) may be varied with time over a selected range of wavelengths that…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.