Plasma diagnostics in pulsed plasma doping system

Summary form only given, as follows. As semiconductor devices continue to shrink in size, demands for the formation of ultra-shallow-junctions (USJ) are increasing. Pulsed plasma doping (P/sup 2/LAD) has emerged as a scaleable and cost effective solution to dopant delivery, since it is capable of high dose rates at ultra low energies (0.05-10 keV). When combined with rapid thermal annealing (RTA), laser annealing and other diffusionless methods, this technique is able to produce scaleable shallow doping profiles outside of the productive operating envelope of conventional ion implanters. In P/sup 2/LAD, a pulsed plasma is generated adjacent to the silicon wafer using pulsed biases, typically ranging between -200 V and -5.0 kV. Typical pulse widths range between 5 and 50 /spl mu/s, and pulse repetition rates between 100 and 5000 Hz. Time-resolved Langmuir-probe measurement showed that cold plasma is present during the afterglow period, which may play an important role for process control, e.g. charge neutralization and minimal etching. It also showed the presence of primary electron and electron beams during the initial pulse-on stage in both Ar and BF/sub 3/ plasmas while they are stronger in BF/sub 3/ plasma. Also, time averaged ion mass/energy analysis indicated that BF/sub 2//sup +/ is the dominant ion species in the BF/sub 3/ plasmas (>90 %), and BF/sup +/ is the second most abundant ion species. In this study, we propose time-resolved ion mass/energy measurements in various doping conditions.