Cathode-lifetime and stability problems in arc-dischargetype heavy ion sources

The last few years have seen ion implantation become a widely used industrial method. This has resulted in increasing importance being attached to the reliability of implanters and to a satisfactory working time/maintenance relation and other factors which are in some way connected with reproducibility and homogeneity. With these viewpoints in mind, ion sources seem to be the most sensitive components of implanters. Besides the normal ion source operations such as changing feeding material or gas, etc., ion sources need care in the maintenance. Ion source lifetime and reliability problems are of special consequence in the case of heavy-current machines. The excellent, mechanically scanned target chambers have made possible the use of higher and higher currents, but at the same time these currents can cause lifetime problems which affect the profit of expensive high current machines.