Method and apparatus for measuring the doping density profile of a semiconductor layer

摘要

The doping density profile and thus the process-related parameters which control the operation and performance of a semiconductor layer, such as that in metal-insulator-semiconductor (MIS) device are reliably determined by determining the difference in the measured and calculated band bendings of a semiconductor layer in accumulation mode. In addition, high and low frequency C-V measurements of the MIS device are performed in order to calculate a second band bending and to approximate the doping density profile of the semiconductor layer. Based upon the approximated doping density profile, an approximate band bending curve is generated. The difference between the approximate and second band bending curves is then compared to the difference between the measured and calculated band bendings of the semiconductor layer in accumulation to determine the variance therebetween. The doping density profile is repeatedly revised until the variance is less than a predetermined amount so that the approximate doping density profile, and the process-related parameters calculated therefrom, are unique and reliable.