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A comparison of heavy-ion-induced single-event transients (SETs) in silicon–germanium heterojunction bipolar transistors (SiGe HBTs) fabricated on both bulk and silicon-on-insulator (SOI) substrates is presented. Experimental heavy-ion data show a reduction of sensitive volume of ≈ 350 × for the SiGe HBTs fabricated on SOI compared to those on a bulk substrate. Furthermore, the results indicate that the sensitive volume of the SOI SiGe HBTs is confined to the intrinsic device. These results have been confirmed using pulsed laser data and TCAD simulations. Limiting the charge collection depth of SiGe HBTs by fabricating them on SOI facilitates correlation of ion and laser results. The improved ease of correlation is a result of suppressing diffusive charge collection mechanisms that are difficult to replicate with the charge deposition profile generated by two-photon absorption using a tightly focused laser beam. However, a potential issue with pulsed laser testing is determining the loss of the pulse energy through the buried oxide, which requires detailed knowledge of the semiconductor platform. Overall, the reduction of sensitive volume for the SOI SiGe HBTs compared to those on a bulk substrate is a clear advantage from a single-event upset vulnerability perspective. [ABSTRACT FROM AUTHOR]

The single-event transient response of a high-voltage complementary SiGe-on-silicon-on-insulator technology is investigated along with its temperature dependence using a pulse laser. The p-n-p silicon-germanium heterojunction bipolar transistor (SiGe HBT) shows a larger transient peak amplitude compared to the n-p-n SiGe HBT, which is largely related to the differences in total device volume and peak germanium content between the p-n-p and n-p-n devices. The effects of temperature on the transient response are also investigated using heaters and sensors mounted directly on the device-under-test package. The collector transient peak amplitude shows a negative temperature coefficient for a $V {_{\text {CB}}}$ of 0-V condition, for both the n-p-n and p-n-p devices. However, the temperature dependence of the transient peak amplitude becomes significantly weaker at $V {_{\text {CB}}}>0$ V. Calibrated TCAD simulations were performed to better understand the temperature dependence, and the simulations indicated that the electric field and mobility at higher $V {_{\text {CB}}}$ have a reduced temperature dependence than at a $V {_{\text {CB}}}$ of 0 V. The effects of self-heating are also explored using TCAD simulations and show that even under aggressive self-heating conditions, there is only less than 10% reduction in transient peak amplitude with the self-heating models turned on. The results shown suggest that this particular SiGe technology can be used for environments where highly energetic particles and high temperatures are encountered simultaneously. [ABSTRACT FROM AUTHOR]

Safe-operating-area (SOA) in a high-voltage complementary silicon–germanium (SiGe) (= n-p-n + p-n-p) on silicon-on-insulator (SOI) technology is investigated from 24 °C to 300 °C. Three key reliability degradation regions are identified, including: 1) high-current; 2) mixed-mode; and 3) high-power. The degradation mechanisms, which are operative, including Auger damage, mixed-mode damage, and electrothermal runaway as well as their temperature dependences are identified. Mixed-mode damage exhibits a strong negative temperature coefficient for both n-p-n and p-n-p SiGe heterojunction bipolar transistors (HBTs) up to 300 °C, which leads to an increase in the SOA from a high-voltage perspective. Electrothermal boundaries are also explored by finding JC,{\textsf {crit}} and V{\textsf {CB},{\textsf {crit}}} across the JC – V\textsf {CB} plane up to 300 °C. Both n-p-n and p-n-p SiGe HBTs show an increase in the SOA for the electrothermal boundary as temperature increases. High-current-induced damage, on the other hand, exhibits a positive temperature coefficient, which implies that high current drive should carefully be considered when using SiGe HBT circuits operated in a high-temperature environment. However, at very high temperatures (>200°C), the high current damage processes show annealing properties, which implies that at sufficiently high temperatures, annealing can dominate over Auger damage and potentially extend the SOA of the technology. [ABSTRACT FROM PUBLISHER]

Total ionizing dose (TID) effects are evaluated for a high-voltage (>30 V) complementary SiGe on SOI technology. Devices are irradiated with 10-keV X-rays at doses up to 5 Mrad(SiO2). The results depend strongly on collector-to-emitter bias, in both forward- and inverse-mode. An anomalous reduction in current gain at high injection in forward-mode operation is observed at doses >500 krad(SiO2). Calibrated 2-D TCAD simulations suggest that this high injection phenomenon is primarily due to interface traps near the STI/Si interface, which is exhibited as a collector resistance increase in the forward Gummel characteristics. Additionally, a strong collector doping dependence is observed, which indicates that this is primarily driven by the thick and lightly doped collector used in this technology. These results illustrate, that high concentrations of interface traps at the STI can have a strong impact on the forward-mode TID response of SiGe HBTs. [ABSTRACT FROM PUBLISHER]