Introduction

The invention relates on a new configuration of the plasma chamber cavity for Electron Cyclotron Resonance (ECR) ion sources, for particle accelerators. The new structure is characterized by a non-uniform cross section, following better the magnetic field structure. In addition, a new microwave launch scheme is proposed on the chamber wall.

Technical features

The idea consists in a resonant cavity containing the magnetized plasmas of  ECR ion sources that breaks the cylindrical symmetry used so far. The new shape of the cavity is basically imposed by the 3D structure of the plasma (and therefore of the magnetic field) and guarantees greater efficiency in electrons heating process. These new structures also allow the use of a microwave launching systems consisting of waveguides obtained in the same structure of the chamber, from which diffractive slits irradiate the RF power. This also allow a profound optimization of the cooling systems and spaces in general. It is a new concept of Radio Frequency (RF)-plasma coupling in ECR ion sources which is proposed with two innovative approaches: a) a  new shape of the plasma chamber for more efficient heating of electrons; b) reconfiguration of the  microwave launching system by means of radiant slots along the side walls of the chamber.

Possible Applications

Ion source production for:

• Particles Accelerators;
• Plasma-enhanced CVD and PVD processes;
• Industrial applications;
• Microelectronics;
• Material analysis and treatment;
• Hadrontherapy.

Advantages

• More space in the injection flange;
• Better coupling of the electromagnetic field;
• Optimization of plasma confinement;
• Maximization of overall efficiency.