Uncertainty of numerical simulation in CV profiling is in fact a problem of uniqueness. The problem has been discussed in this work. A point by point multiple sweeps numerical algorithm consists of three aspects: （1） The dopant profile is obtained by several sweeps

and smaller convergent criterion is used for a following sweep; （2） Each sweep is composed of a point by point extraction process starting from the lowest bias point to the highest bias point; （3） The gradient sign at any point of the extracting dopant profile in the overall simulation process is defined by the sign of the same point of the profile obtained by the depletion approximation. The algorithm can not only deal with very steep dopant profiles

but also can cope with the extreme case

a step change of dopant distribution. Good agreement between the extracted profiles and the theoretical ones has been obtained.