Plasma wafer processing tool having closed electron cyclotron resonance
US5189446A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 1991 |
| Grant date | Feb 23, 1993 |
| Priority date | — |
| Expiry date | May 17, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32678
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A cylindrical plasma reaction chamber is equipped with a pair of axially separated solenoid coils and a multipole magnet structure extending between the coil pair. An axially-directed magnetic field and a transverse cusp field are respectively provided by the coils and the magnet. A working gas is contained within the chamber and is excited by applied microwave energy. The strengths of the two magnetic fields and the microwave frequency value are selected to produce a substantially closed electron cyclotron resonance (ECR) zone of proper size. This ECR zone is located axially between the solenoid fields. Baffling is used to separate the closed plasma ECR zone from the workpiece region of the chamber. A semiconductor wafer is positioned within the workpiece region to intercept most plasma particles which follow the axially directed magnetic lines passing through the ECR zone. Few of the particles from the closed ECR zone travel to destinations other than the wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.