电子学报2025，Vol.53Issue(12)：4665-4670,6.DOI:10.12263/DZXB.20250733
亚20nm FinFET工艺温度传感器低温总剂量效应研究
Total Ionizing Dose Effects at Cryogenic Temperatures on a Sub-20 nm FinFET Temperature Sensor
摘要
Abstract
This paper investigates the cryogenic total ionizing dose(TID)effects on a temperature sensor fabricated in a sub-20 nm bulk silicon FinFET technology,targeting applications in extreme environments such as deep-space explora⁃tion.The sensor core utilizes a bandgap reference circuit based on PNP bipolar junction transistors.Theoretical analysis re⁃veals that the degradation of bipolar transistors under irradiation at 290 K or 110 K manifests an increase in the base recom⁃bination current.However,the underlying dominant mechanisms are fundamentally different.At room temperature(290 K),the degradation is primarily governed by an increase in the interface trap density,consistent with the classical model involv⁃ing hydrogen ion(H⁺)drift leading to the breaking of Si-H bonds.In contrast,under cryogenic conditions(110 K),the drift motion of H⁺ ions is effectively"frozen",and the tunneling-assisted recombination mechanism via border traps becomes the main contributor to degradation.Given that the border trap concentration at 110 K is significantly higher than the interface trap concentration at 290 K,a pronounced enhancement of radiation damage at cryogenic temperatures is observed.Circuit analysis and simulation validation demonstrate that as the radiation-induced leakage current increases from 0 nA to 100 nA,the bandgap reference voltage undergoes significant changes,resulting in an approximate 21 bit increase in the output tem⁃perature code.This finding theoretically predicts a positive drift in the temperature code due to irradiation.To experimental⁃ly verify the theoretical analysis,irradiation tests were conducted using a customized cryogenic TID effect test system and a Co⁶⁰ γ-ray source,accumulating a total dose of 1 Mrad(Si)under 110 K and 290 K conditionsrespectively.The experimen⁃tal results unequivocally show that after 1 Mrad(Si)irradiation,the cumulative increases in the temperature code for sensors irradiated at 110 K reach 37 bits and 30 bits,respectively,which are substantially greater than the 9 bit increase observed un⁃der 290 K room-temperature irradiation.This clear quantitative evidence firmly validates the existence of cryogenic temper⁃ature radiation damage enhancement effects.This study provides crucial theoretical insights and experimental data for the design and radiation hardening of FinFET integrated circuits,particularly sensors relying on bipolar devices,operating in ex⁃treme low-temperature and high-radiation environments.关键词
FinFET/温度传感器/总剂量效应/低温/双极晶体管Key words
FinFET/temperature sensor/total ionizing dose effects/cryogenic temperature/bipolar junction transistor分类
信息技术与安全科学引用本文复制引用
皮辉斌,吴龙胜,文溢,罗登,喻国芳..亚20nm FinFET工艺温度传感器低温总剂量效应研究[J].电子学报,2025,53(12):4665-4670,6.基金项目
国家自然科学基金(No.62304258) National Natural Science Foundation of China(No.62304258) （No.62304258）
