VIISion PLUS performance improvements

In a continuous improvement program that began fall ´97, several improvements have been made to the VIISion PLUS batch high current ion implanter, and others are being incorporated. First, the auto-setup success rate at 2 keV has been improved. Modified set-up algorithms have consistently yielded >80% auto-setup success rates. Second, an aperture modification, and improved control of beam size and hot spot location, have reduced the variance of Al contamination levels. Third, the limiting factor on manipulator life when running spec B11 at 5 keV has been identified as a deterioration (coating or erosion) of the surface of the suppression electrode facing the arc chamber, leading to high glitch rates. Fourth, some design changes in the VIISion 200 PLUS accel/beam gate area that simplify maintenance will be described. Fifth, a decel technique for greatly increasing sub 2 keV throughputs is being developed. Energies down to 100 eV would be achievable, with throughputs comparable to 2 keV drift. SIMS profiles are shown. Finally, source life improvements at one customer site is presented. Results and status of these improvements are presented, along with an evaluation of testing incorporating some of these improvements. That testing concentrates on low energy performance