Design Of MOSFETs' Parasitic Capacitances Measurement Method Based On CBCM

Charge-based capacitance measurement(CBCM)method is the most accurate method when measuring the on-chip parasitic capacitances.In this thesis we proposed two improved CBCM meathod.One is the self-differential(SD)CBCM.It is specifically applied to measure a single differential capacitance like MOSFET gate capacitance with high accuracy.SDCBCM has two main advantages.First,it employs a newly proposed self-differential method to derive the capacitance-voltage(C-V)curve of gate capacitance,thus avoid the amplification of systematic error during the differentiation.Second,it can operate at a very high frequency(500 MHz or more),which for the first time allows the gate capacitance of actual operating frequency to be measured and reduces random error to a very low level.Compared with the previous work,the accuracy of our method is increased by tens of times.Another is the multi-channel(MC)CBCM.Using the multi-channel CBCM technique,we can measure all of the parasitic capacitance components of a MOSFET which are related to its terminals,such as the gate-to drain capacitance,gate-to-source capacitance,gate-to-bulk capacitance,and so on.We can measure capacitances of sub-femto-farad level in all regimes,including the cut-off,linear and saturation regimes.It is the first time that these research works can be done in such a high accuracy.Both CBCM methods are realized in GSMC 0.18?m technology.The measurement result of many different MOSFETs on-chip can verify our work.