On the Measurement of Impurity Atom Distributions by the Differential Capacitance Technique [Letter to the Editor]

In a recent paper,
¹
it was shown that the profile inferred from differential capacitance measurement
^2–5
of semiconductor junctions is not that of the impurity atom distribution but, instead, that of the majority carrier distribution. For this reason, conventional differential capacitance measurements can be used to evaluate the impurity atom distribution only in charge neutral semiconductor material (where the majority carrier density equals the density of ionized impurity atoms). This requirement of charge neutrality limits the applicability of this measurement technique to semiconductor material containing a minimum impurity atom density of about 10
¹⁶
atoms/cm
³
.