Analysis of Capacitances in Asymmetric Self-Cascode SOI nMOSFETs

Abstract

This work presents a study of the capacitance of asymmetric self-cascode silicon-on-insulator (ASC SOI) MOSFETs with similar gate areas and different gate lengths. Experimental results of total gate capacitance of different ASC are presented and complemented with the results of two-dimensional simulations. The transcapacitances are explored through two-dimensional simulations. Results show that different channel lengths of the composite transistors have more influence in the depletion region of the capacitance curves for low VDS. The gate-source and gate-drain capacitances show opposite trends with the change in the lengths of source and drain transistors, despite of the VDS applied.