This paper discusses the total dose radiation characteristics of 1.0μm SIMOX MOSFETs
CMOS/SIMOX inverters and ring oscillators.The thin film SIMOX MOSFETs have a good radiation characteristics.The radiation induced threshold voltage shifts are less than 1.0V when the irradiation dose is 3x105rad(Si) and 7x105rad(Si) for N-and P-MOSFET
respectively.The ring oscillator can operate well after irradiation of 5x105rad(Si) γ ray.Its propagation delay increases from 237ps to 328ps.The radiation tolerance of PMOSFET is better than that of NMOSFET.The radiation induced leakage of NMOSFET is mainly caused by the parasitic backchannel transistor.