Plasma processing method
US6320154A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 1999 |
| Grant date | Nov 20, 2001 |
| Priority date | — |
| Expiry date | Apr 27, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/022
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An objective of this invention is to provide a plasma processing method that is capable of reducing particle contamination during plasma processing performed upon a semiconductor wafer. If the use of electron cyclotron resonance to generate a plasma and form a thin film of SiOF or the like is used by way of example, a sheath zone of a few mm thick is formed between the wafer and the plasma, and particles are trapped within a boundary zone between the sheath zone and the plasma. At this point, a microwave power is not dropped suddenly to zero after the film-formation processing, but is reduced to a lower level of, for example, 1 kW and is held for 10 seconds. This reduces the plasma density and thickens the sheath zone, so that particles are held away from the wafer surface. When the microwave power is subsequently cut, the particles move freely around, but only a small proportion thereof adhere to the wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.