International Conference on Solid State Devices and Materials

We experimentally characterize effective mobility of Si n-channel MOSFETs by using the split C-V method at temperatures from 300 K to 4 K. It is found that the capacitance decreases with increasing measurement frequency in split C-V and that the influence is more pronounced at low temperatures, which cause inaccuracy of estimated effective mobility. Therefore, we introduce a method to extract surface carrier concentration and resulting mobility accurately by using quasi-static split C-V (QSCV) measurements and experimentally show that effective mobility estimated by QSCV at 4 K is in good agreement with Hall mobility. As a result, QSCV is an effective method to extract the effective mobility of MOSFETs at cryogenic temperatures.