Abstract：The interdigital capacitance is theoretically calculated using the Schwarz-Christoffel transform method. Through a combination of theoretical calculations and simulation analysis, the study investigates the influence of the geometric size of the interdigital capacitor structure and the number of electrodes on the on-chip small capacitance standard cell. The preparation and test verification of interdigital capacitor standard units with capacitance values ranging from 10 fF to 100 fF have been realized. Test results indicate that the on-chip small capacitance standard cells become more linearly dependent on the changes in capacitance as the length and number of interdigitated electrodes increase. In the range of 10 fF to 100 fF, the standard uncertainty of an on-chip small capacitance standard cell is better than 0.5% × C + 100 aF (where C is the capacitance). It provides a research basis for the further production of a wider range of on-chip small capacitance standard cells.
2025, Vol. 46 
