Variability of MOSFET Series Resistance Extracted from Individual Devices: Is Direct Variability Measurement Possible?

Source-to-drain series resistance (RSD) of a large number of identically designed MOSFETs was extracted using a recently proposed single-device method. By examining statistical correlations with other device parameters, it was confirmed that variability of the extracted RSD values does not correspond to real series resistance variability, but is mainly caused by some non- RSD variability sources. This suggests that, for the single-device method to work, non- RSD variability needs to be reduced by averaging multiple devices, or using wide channel devices.