P. Dewolf et al., QUANTIFICATION OF NANOSPREADING RESISTANCE PROFILING DATA, Journal of vacuum science & technology. B, Microelectronics and nanometer structures processing, measurement and phenomena, 16(1), 1998, pp. 320-326
In nanospreading resistance, the resistance measured at a particular p
osition on the sample cross section is not exclusively determined by t
he carrier concentration at this position, but by the entire surroundi
ng carrier profile. The correct evaluation of this spreading effect re
quires a detailed calculation, leading to a deconvolution algorithm, w
hich recovers the charge-carrier profile from the measured resistance
profile. In this work, a general scheme for transforming a wide range
of profiles is proposed. The scheme is based upon finite-element calcu
lations of the potential distribution and the current spreading of a c
ircular flat contact current source on a semi-infinite semiconductor s
ample with known carrier distribution. A correction factor database is
formed as a function of typical profile characteristics such as (i) t
he distance to perfectly isolating or conducting boundaries, (ii) carr
ier gradient, and (iii) carrier curvature. In routine operation the tr
ansformation of resistance data into the carrier-concentration profile
is done by interpolation of the database, hereby avoiding the time-co
nsuming finite-element calculations. The latter results in a very fast
calculation of the carrier profile data with an accuracy better than
10%, without any loss in spatial resolution. Examples are given that i
llustrate the accuracy of the method. (C) 1998 American Vacuum Society
.