Gate Capacitance Measurement Using a Self-Differential Charge-Based Capacitance Measurement Method

In this letter, we propose a self-differential charge-based capacitance measurement(SDCBCM) method. It is specifically applied to measure 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 avoiding 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.