P. Bouillon et T. Skotnicki, THEORETICAL-ANALYSIS OF KINK EFFECT IN C-V CHARACTERISTICS OF INDIUM-IMPLANTED NMOS CAPACITORS, IEEE electron device letters, 19(1), 1998, pp. 19-22
Experimental observation of an anomalous ''kink'' effect in C-V charac
teristics of Indium-doped NMOS capacitors is reported and explained, f
or the first time, via the impact of incomplete ionization of Indium,
A new analytical formulation of the total semiconductor capacitance is
developed, that takes incomplete ionization phenomenon into account,
Thanks to this new C-SC(phi(s)) relation, we have demonstrated that th
e carrier freeze-out is responsible for this kink near V-FB in C-V cur
ves, and also for an intrinsic lowering in the threshold voltage, This
kink has been shown to be very sensitive to Indium dose and temperatu
re, It is also demonstrated that the deformation of the C-V characteri
stics due to Indium incomplete ionization may be (and probably has oft
en been) miss-interpreted as appearance of high fixed charge densities
in parameter extraction from C-V fitting, Our analysis is in full agr
eement with experimental results.