Methods and apparatus for contamination control in plasma processing
US5387777A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1992 |
| Grant date | Feb 7, 1995 |
| Priority date | — |
| Expiry date | Jun 24, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S156/916
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Contamination levels in plasma processes are reduced during plasma processing, by prevention of formation of particles, by preventing entry of particles externally introduced or by removing particles spontaneously formed from chemical and/or mechanical sources. Some techniques for prevention of formation of particles include interruption of the plasma by pulsing the source of plasma energy periodically, or application of energy to provide mechanical agitation such as mechanical shockwaves, acoustic stress, ultrasonic stress, vibrational stress, thermal stress, and pressure stress. Following a period of applied stress, a tool is pumped out (if a plasma is used, the glow is first discontinued), vented, opened and flaked or particulate material is cleaned from the lower electrode and other surfaces. A burst of filtered air or nitrogen, or a vacuum cleaner is used for removal of deposition debris while the vented tool is open. Following this procedure, the tool is then be used for product runs. Alternatively, improvement of semiconductor process yields can be achieved by addition of reagents to getter chemical precursors of contamination particulates and by filtration of particulates f…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.