Design and Evaluation of a Radiation-Hardened FDSOI SRAM With High-Reliable Elements and Power Management Circuits for Space Application
Chang Cai, Minchi Hu, Lei Shen, Jun Yu, Gengsheng Chen
Abstract
Designing a radiation-tolerant SRAM-based system poses a significant challenge for space facilities operating in radiation environments. Accurate evaluation of SEE sensitivity, along with the design of radiation-hardened memory cells and power management circuits is crucial, particularly for advanced nanotechnologies. In this article, a radiation-tolerant FDSOI SRAM with two switchable bandgap reference circuits was designed. An additional single event effects (SEE)-hardened selection circuit was used to enable the targeted bandgap reference circuits. The ∼3 × 10−14 cm2/bit saturated single event upsets cross section for the hardened SRAM device was measured by our heavy ion irradiation test. The bipolar bandgap reference circuit-induced single event transients (SET) cross sections were confirmed by comparing different test modes. Besides, the features of 181Ta-induced transients in the bipolar bandgap reference circuit were captured during our experiments. The designed two reference circuits exhibit SEE tolerance, although a few transients can be observed in the bipolar circuit, leading to a ∼30% increase in output voltage. The MOS bandgap reference circuit exhibits strong radiation resistance but is slightly inferior at controlling temperature drift and maintaining the stability of the reference voltage. The SET measurement results for the bipolar bandgap reference circuit reveal specific radiation sensitivity and potential risks for high-reliable SRAM systems, whereas the full MOS structure can further enhance the radiation tolerance of the entire system.