Method and apparatus for processing wafers under pressure
US6745494B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 30, 2002 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Dec 30, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/67775
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A system for high-pressure drying of semiconductor wafers includes the insertion of a wafer into an open vessel, the immersion of the wafer in a liquid, pressure-sealing of the vessel, pressurization of the vessel with an inert gas, and then the controlled draining of the liquid using a moveable drain that extracts water from a depth maintained just below the gas-liquid interface. Thereafter, the pressure may be reduced in the vessel and the dry and clean wafer may be removed. The high pressure suppresses the boiling point of liquids, thus allowing higher temperatures to be used to optimize reactivity. Megasonic waves are used with pressurized fluid to enhance cleaning performance. Supercritical substances are provided in a sealed vessel containing a wafer to promote cleaning and other treatment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.