Comparison of Total Ionizing Dose Effect on Tolerance of SCL 180 nm Bulk and SOI CMOS Using TCAD Simulation

Abstract

The long-term reliability of metal oxide semiconductor (MOS) devices in space technology depends on the total ionizing dose (TID) effect. In MOS technology, power consuming, expensive, and bulky triple modular redundancy and shielding techniques are required to address radiation related issues. In this work, we simulate Semi-Conductor Laboratory (SCL) 180 nm silicon on insulator (SOI) and Bulk NMOS device for comparative study of TID effects in space technology applications. Both devices after simulation show 0.42 V and 0.62 V threshold voltage, respectively. Devices are irradiated for 15 s to achieve doses of 100 K Rad, 200 K Rad, 500 K Rad, 800 K Rad, 1 M Rad, respectively with different dose rates. Bulk 180 nm NMOS was found to be more radiation-sensitive than SOI devices. Dose rate (DR) effect of 35 µV on a Bulk device and 16 µV on SOI was observed. 267% on Bulk and 256% on SOI leakage current shift observed due to radiation. Devices show the dose rate sensitivity with varying leakage current from the range of 1.8 to 3nA/um. In both the devices, leakage current is generated because of interface charge trapped due to radiation and charge trapped. Post radiation major shift transconductance characteristics are observed.