Comprehensive Study on the Total Dose Effects in a 180-nm CMOS Technology

The effects of total ionizing on a 180-nm CMOS technology are comprehensively studied. Firstly, we show new results on the hump effect which has strong relationship to the STI corner oxide thickness. Secondly, the leakage current degradation in various devices after radiation is investigated. For the intra-device leakage, both body doping concentration and STI corner thickness play very important roles. For the inter-device leakage, due to the low electric field at the STI bottom, it is found to be insensitive to ionizing radiation. Thirdly, a method for extracting the effective threshold voltage of the sidewall parasitic transistor is proposed by studying the leakage output characteristics. Finally, we find that the drain saturation current increases in NMOS transistors after radiation, especially in the narrow-channel ones.