An "Integrated Device and Circuit Simulator"for thin film(50~400nm) submicron(0.5~1.0μm) and deep submicron(0.15
0.25 and 0.3.5μm)CMOS/SOI integrated circuits has been developed.This simulator combines device numerical simulation with circuit numerical simulation by coupling connecting stage of SOI MOSFET using integrated numerical model.The characteristics and mechanism of thin film submicron and deep submicron CMOS/SOI ring oscillators are discussed.The simulation results are identical with experimental results.