Mini Microwave Plasma Cracker Source for the Hybrid Generation of Atoms and Ions from Oxygen Gases in Small Vacuum Chambers
The hybrid plasma source for oxygen gases MPS-ECR-HO is a fully UHV compatible component for most demanding MBE applications and surface modifications, suitable for a wide range of vacuum levels (UHV to HV) in small vacuum chambers. Microwaves with a frequency of 2.45 GHz are generated by a microwave magnetron and coupled into the plasma chamber, where a plasma is excited and the microwaves absorbed. The plasma density is enhanced by the magnetron cyclotron resonance effect, provided by a 86 mT magnetic quadrupole arranged around the plasma chamber. The electrons undergo electron cyclotron resonance (ECR) motion, which greatly enhances the electron path length and therefore the probability of collision with other molecules and subsequent ionisation.This hybrid source combines atom source and ion source characteristics to produce a source, which behaves like the atom source until potentials are applied to the extraction grids, when oxygen ions with controllable energy (50 - 1500 eV) are then added to the beam.
The source is fully bakeable with outstanding cooling from a full length water-jacket. With additional sets of the user-exchangeable extraction grids or aperture plates, the source can be easily reconfigured for reducing gases or as an atom source, downstream plasma source or hybrid source. The small mounting flange (DN40CF) makes the source suitable where space constraints are an issue.