Ion source requirements for a radio frequency high-energy ion implanter

Over the last several years, high-energy (in MeV range) ion implantation has become an integral part of mainstream semiconductor device manufacturing. The rapid growth in use of high-energy implanters has been driven by process and performance requirements for sub 0.25 mu m device nodes. At Eaten, we have developed an rf linac based high-energy implanter, NV-GSD/VHE, capable of delivering in excess of one particle mA of B+ beam current at energies approaching 1.7 MeV. The Linac's output energy is almost doubled if B++ ions are used. However, for fixed implanter throughput an ion source capable of sourcing similar to 5 particle mA of B++ is required. The 90% un-normalized emittance at 90 keV should be less than 150 pi mn mrad. We are investigating three completely different ion source technologies, hot cathode, rf-driven bucket, and electron cyclotron resonance ion sources as candidates. The present performance and the future expectation from each of these ion source technologies will be discussed. (C) 1998 American Institute of Physics.