Low dose performance of a high current ion implanter in production

The ion implant dose requirements of a modern semiconductor manufacturing product flow span a range of approximately 1E11 cm/sup -2/ to 1E16 cm/sup -2/. High current implanters are typically operated in applications that require doses greater than 1E14 cm/sup -2/. The low dose capability of a high current ion implanter is demonstrated for doses less than 5e12 cm/sup -2/ and beam currents less than 25 uA. The performance is studied using various metrology tools and verified using device data from a CMOS integrated circuit manufacturing process. Thermal wave and optical densitometry sensitivity and repeatability is determined over various time intervals. Adjusting threshold voltage with ion implantation is discussed.