CMOS technologies in the 100 nm range for rad-hard front-end electronics in future collider experiments

Abstract

130 nm and 90 nm CMOS processes are going to be used in the design of mixed-signal integrated circuits for the readout of detectors in the future generation of HEP experiments. In applications such as inner SLHC detectors, these ultra-deep submicron systems will have to stand total doses of ionizing radiation of the order of 100 Mrad and beyond. While the scaling of the gate oxide thickness to about 2 nm gives a high degree of radiation tolerance, issues such as the gate tunneling current and the sidewall leakage associated to lateral isolation oxides must be investigated. This paper provides an analysis of an extensive set of irradiation tests carried out on 130 and 90 nm CMOS transistors belonging to commercial technologies. With special focus on the design of analog front-end circuits for silicon pixel and strip detectors, the impact of ionizing radiation on the noise performance is evaluated and the underlying physical degradation mechanisms are pointed out to provide criteria for improving radiation hardness properties.