A modified ion sputter source with increased lifetime

The Cs sputter ion source HVEE 860-C has shown significant erosion of inner parts after an operation time of some thousand hours. This is caused by Cs ions generated at hot surfaces outside the spherical ioniser surface. The calculated trajectories of these ions and the erosion patterns show an excellent correspondence. The suppression of the disturbing ions has resulted in increased lifetimes of the ion source and an improved focus of the primary Cs ions on the sputter target. The modified sputter ion source is still in operation without any maintenance (about 3000 operating hours at October 2003).