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This paper presents a 2 GHz low noise amplifier (LNA) implemented in 180 nm complementary metal oxide semiconductor (CMOS) technology designed for cryogenic temperatures as well as its measurement results at both room temperature and 77 K. A modified approach to classical LNA design has been adopted. The matching of the LNA has been performed by external discrete components such that $S_{11}$ and $S_{22}$ of the LNA between 2.025 and 2.12 GHz (designated for space communications) are below −10 dB at both 77 K and 297 K. At 77 K, the designed LNA achieves 18 dB gain, 35.4 K noise temperature, and +3 dBm IIP3. IIP3 performance of the LNA at cryogenic temperatures has been analyzed in particular, and the linearity improvement by using the proposed approach has been demonstrated. Moreover, the designed LNA was irradiated with 650 krad gamma radiation. Even though the LNA is not specifically radiation-hardened, no degradation on its performance has been observed. [ABSTRACT FROM AUTHOR]

In a Jupiter exploration mission, the Jovian radiation belt has a strong radiation characteristic with high energy and large flux. Based on the data from the radiation test on device, the Jovian radiation belt model and solar proton model, we introduce a method to evaluate the failure possibility and the confidence level of the RDM (radiation design margin) caused by the total ionizing dose after shielding layers, which includes the radiation environment variability in the Jovian mission. Using this method, we can approach a balance among the device ability, shielding thickness, and failure probability. We find that the Weibull distribution fits the failure possibility of the TL084 experimental data well. For a mission in an equatorial orbit with an altitude of 10 radii of Jupiter, the proton flux of the radiation belt is 3 orders of magnitude larger than solar proton. When the shielding thickness increases and the duration of mission decreases, the failure probability of the TL084 caused by the total dose decreases. The mean lifetime of the TLD84 is shorter than 2 weeks after a 10 mm aluminum shielding. In addition, we calculate the failure rate of the TL084. When the shielding layer is thinned and the orbiting period increases, the device fails faster. When the RDM is set as 2, the confidence level after 1 mm aluminum shielding is about 89%. [ABSTRACT FROM AUTHOR]

A comprehensive model is presented which enables the effects of ionizing radiation on bulk CMOS devices and parasitic structures to be simulated with closed form functions. The model adapts general equations for defect formation in uniform SiO2 films to facilitate analytical calculations of trapped charge and interface trap buildup in radiation sensitive shallow trench isolation (STI) oxides. An approach whereby defect distributions along the bottom and sidewall of the STI are calculated, incorporated into implicit surface potential equations, and ultimately used to model radiation-induced leakage currents in MOSFET structures and integrated circuits is described. The results of the modeling approach are compared to experimental data obtained on 130 and 90 nm devices and circuits. The features having the greatest impact on the increased radiation tolerance of advanced deep-sub-micron bulk CMOS technologies are also discussed. These features include increased doping levels along the STI sidewall. [ABSTRACT FROM AUTHOR]