We investigated the electrical characteristics and the junction depth of ul
tra-shallow junctions formed by using the plasma-doping method. Compared wi
th ultra-low energy boron-ion implantation at 500 eV, the junctions formed
with the plasma-doping process exhibited shallow junction depths and low sh
eet resistances. The junction depths of the plasma-doped samples were 150 A
ngstrom and 330 A after annealing for 10s at 900 degreesC, respectively. Fo
r the same junction depth, the sheet resistance of the B2H6 plasma-doped sa
mple wa an oder of magnitude less than that of the 500-eV B-ion implanted s
ample. Cross-sectional transmission electron microscopy and deep level tran
sient spectroscopy showed that the defects formed by the B2H6 plasma-doping
process could be removed by annealing at 950 degreesC for 10 s. The scalin
g of metal-oxide-semiconductor field-effect-transistor (MOSFET) device chan
nel lengths for high-speed application requires the scaling down to 30 simi
lar to 40 nm for next-generation 0.1-mum MOSFET devices [1]. Compared with
n(+)/p junction, it is difficult to form an ultra-shallow p(+)/n junction d
ue to boron channeling and to transient-enhanced diffusion related to extra
interstitials generated during the implantation method is considered as a
good candidate for achieving ultra-shallow junction profiles because of its
ultra-low energy, high throughput and room temperature operation [4]. If p
lasma doping at an energy level of 100 eV used, the locations of defects ge
nerated by plasma implantation are very close to the Si surface. It is know
n that the Si surface is an efficient sink for the removal of point defects
. Therefore, we expect the transient-enhanced diffusion for a plasma doping
process to be almost negligible. In this study, we investigated the charac
teristics of an ultra-shallow junction formed by plasma ion implantation as
an alternative to the ion-implantation process.