W. Vandervorst et al., INFLUENCE OF THE SUBSTRATE DOPING LEVEL ON SPREADING RESISTANCE PROFILING, Journal of vacuum science & technology. B, Microelectronics and nanometer structures processing, measurement and phenomena, 14(1), 1996, pp. 404-407
A study has been performed of spreading resistance probe measurements
on a series of 200-nm-deep boron implants into p-type substrates with
varying doping levels ranging from 3X10(14) up to 4x10(17)/cm(3). All
implants were performed under the same conditions and with the same do
se. However, routinely generated spreading resistance carrier profiles
from different sites consistently indicate abnormally high doses and
shoulder peak artifacts at the back side of the implant profile for th
e more highly doped substrates. It is proposed that these artifacts ca
n be related to pressure-enhanced carrier spilling effects underneath
the probes. When performing a Laplace-based correction and hence negle
cting any carrier spilling effects, the correction factor scheme react
s upon the position of the on-bevel junction position instead of on th
e vertical junction position which can be considerably deeper in the p
resence of pressure-enhanced spilling. The observed artifacts can be r
educed within Laplace calculations by allowing for more barrier resist
ance and consequently a larger contact radius. (C) 1996 American Vacuu
m Society.