Andrew M. Ray

Optima MD: Mid‐Dose, Hybrid‐Scan Ion Implanter

The emergence of higher‐dose and lower‐energy halo and source‐drain extension implants for 90 and 65‐nm nodes drove the design of Axcelis’ Optima MD ion implanter. The Optima MD extends the proven process performance of traditional medium‐current implanters over an energy range of 1 keV to 250 keV for singly‐charged ion species with beam currents ranging from 1 pμA to 4800 pμA. The Optima MD comprises a hybrid‐scan beamline architecture, a new endstation, and a new control system that offers the user more flexibility in data acquisition and statistical process control. The beamline has the capability to provide milliamp beam currents in the low energy (<5 keV) range. The use of an aggressive final deceleration (decel) in combination with a final angular energy filter (AEF) enables this productivity improvement of higher beam currents while mitigating the risk of energy contamination. In this paper the new beam transport system that reduces space charge blowup and maintains focus control at low energies is...