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A model for radiation-induced interface-trap buildup distinguishes among the contributions of hydrogen dimerization, electron recombination, and electric field mechanisms, quantitatively explaining time-dependent and true dose rate effects in irradiated bipolar isolation oxides. Hydrogen dimerization is the dominant ELDRS mechanism for devices exposed to medium \ H2 concentrations (1% per volume), whereas \ H2 cracking dominates as \ H2 concentration is increased further. Electron recombination mechanisms contribute at high dose rates (> 100~\ rad(\ SiO2)/{\ {s}}), but are not the dominant ELDRS mechanism at dose rates lower than 100 \ rad(\ SiO2)/{\ {s}}). [ABSTRACT FROM AUTHOR]

A physics-based TCAD model for enhanced low-dose-rate sensitivity in linear bipolar devices is developed. Quantitative agreement is found with measured data over a wide range of dose rates and H2 concentrations. Analysis of the degradation effects of individual defect types, the implementation of which has been informed by first principles calculations, provides insights into the mechanisms behind enhanced low-dose-rate effects in different hydrogen environments. The effects of initial defect concentration and location and the energetics of the defect-related reactions are explored. Conclusions are drawn about the roles of molecular hydrogen and hydrogenated defects in the radiation response of these devices. [ABSTRACT FROM PUBLISHER]

Laser-induced current transients are measured on uniaxially stressed silicon (Si) N-f/P diodes using a high speed measurement system. Controlled external mechanical stress along the <110> direction is applied via a four-point bending jig while the samples are irradiated using a cavity-dumped dye laser with a wavelength of 590 nm. A decrease in the peak current is observed for increasing tensile stress applied to the diode. Unlike tensile stress, compressive stress increases the peak current. Charge collection is observed to decrease with tensile and increase with compressive stress. These results suggest that uniaxial mechanical stress alters the current transients due to strain-induced changes in electron mobility along the <001> direction. The average effective electron mass along the <001> direction increases with tensile and decreases with compressive stress resulting from the splitting of de- generate conduction band valleys and the repopulation of electrons from higher to lower valleys. The Florida object oriented device simulator (FLOODS) is used to explain the mechanism of current transients in unstressed and stressed diodes. FLOODS is also used to predict results for values of applied stress (∼ 1 GPa) beyond those that can be obtained using the bending jig (∼ 240 MPa). [ABSTRACT FROM AUTHOR]