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Proton Radiation Damage on SiGe:C HBTs and Additivity of Ionization and Displacement Effects

Proton irradiation results are shown here for three different SiGe:C HBT technologies from IHP Microelectronics. High damages are observed although the transistors remain usable for their application on the Super-LHC. Considerations on the ionization and displacement effects additivity are also presented in order to validate parameterized experiments. This study shows a reasonable agreement between proton irradiations and previous gamma and neutron irradiations.

Gamma Radiation Effects on Different Varieties of SiGe:C HBT Technologies

We have studied the ionization damage produced by gamma irradiation on transistors from three different varieties of SiGe:C HBT technologies from Innovation for High Performance Microelectronics (IHP), Germany. The results show strong gain degradations at the highest doses, with an indication of damage saturation. We did not observe strong differences in radiation tolerance among the three different technologies. These studies are in the framework of the radiation assurance tests of SiGe BiCMOS technologies for their possible application in the front-end readout electronics of the detector modules of the future ATLAS upgrade for the Super-LHC, but space-oriented applications are also considered. A comparison is presented with previous gamma irradiations of different SiGe technologies in the literature.

IHP SiGe:C BiCMOS Technologies as a Suitable Backup Solution for the ATLAS Upgrade Front-End Electronics

In this study we present the results of radiation hardness studies performed on three different SiGe:C BiCMOS technologies from Innovation for High Performance Microelectronics (IHP) for their application in the Super-Large Hadron Collider (S-LHC). We performed gamma, neutron and proton irradiations on the bipolar section of these technologies, in order to consider ionization and atomic displacement damage on electronic devices. Results show that transistors from the IHP BiCMOS technologies remain functional after the radiation levels expected in the inner detector (ID) of the ATLAS Upgrade experiment. These technologies are one of the candidates to constitute the analog part of the Front-End chip in the ATLAS-upgrade experiment, in the S-LHC.

IHP SiGe:C BiCMOS technologies as a suitable backup solution for the ATLAS upgrade Front-End electronics

In this study we present the results of the radiation hardness studies performed on three different SiGe:C BiCMOS technologies from Innovation for High Performance Microelectronics (IHP) for their application in the Super-Large Hadron Collider (S-LHC). We performed gamma, neutron and proton irradiations on the bipolar module of the technologies, in order to consider all radiation damage mechanisms on the electronic devices. The results show that transistors from the IHP BiCMOS technologies remain functional after the radiation levels expected in the S-LHC. These technologies are one of the candidates to constitute the analog part of the Front-End chip in the ATLAS-upgrade experiment, inside the S-LHC.

Radiation Studies of Power LDMOS Devices for High Energy Physics Applications

We present radiation hardness studies performed on LDMOS devices included in a 0.25 μm SiGe BiCMOS technology from IHP Microelectronics. Results show degradation of devices performances only beyond 1 × 10¹⁵ n_eq/cm².

Performance of the SiGe HBT 8HP and 8WL technologies after high dose/fluence radiation exposure

An assessment of the radiation tolerance of the latest generation IBM silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) technologies (SiGe 8WL and SiGe 8HP) at extreme dose/fluence is reported. These BiCMOS technologies are of great interest for analog readout circuits in high energy physics detectors, especially the planned upgrade of the ATLAS detector for the upgraded Large Hadron Collider (sLHC) in Geneva, Switzerland. These third-generation, 130 nm SiGe HBTs show promise to operate at lower power than CMOS circuits provided that they can be shown to be sufficiently radiation tolerant. This study presents evidence of the radiation tolerance of these two candidate technologies with parametric measurements after irradiation up to a fluence of 1016 1 MeV equivalent neutrons/cm2 and a gamma dose of 100 Mrad (SiO2).

Radiation hardness evaluation of a 130 nm SiGe BiCMOS technology for the ATLAS electronics upgrade

Final results for a comprehensive radiation hardness evaluation of a high performance, low cost, 130nm SiGe BiCMOS technology are presented. After a survey of several available SiGe technologies, one was chosen in terms of performance, power consumption, radiation hardness, and cost and it is presented as a suitable technology for the front-end electronics of the Inner Detector and the Liquid Argon calorimeter. Gamma, neutron and proton irradiations have been performed up to target dose and fluence values, together with ELDRS assessment.

Evaluation of Two SiGe HBT Technologies for the ATLAS sLHC Upgrade

As previously reported, silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) technologies promise several advantages over CMOS for the front-end readout electronics for the ATLAS upgrade. Since our last paper, we have evaluated the relative merits of the latest generations of IBM SiGe HBT BiCMOS technologies, the 8WL and 8HP platforms. These 130nm SiGe technologies show promise to operate at lower power than CMOS technologies and would provide a viable alternative for the Silicon Strip Detector and Liquid Argon Calorimeter upgrades, provided that the radiation tolerance studies at multiple gamma and neutron irradiation levels, included in this investigation, show them to be sufficiently radiation tolerant.

Bias Conditions in Gamma Radiation Assurance Tests of Bipolar Technologies for HEP Applications

In common irradiation tests performed with electronics to be used in space applications, devices are kept with their terminals shorted together during the irradiation time. However, in HEP experiments, devices are generally biased during the irradiation periods. Therefore, unbiased irradiation tests are not realistic anymore. We have performed systematic experiments irradiating different bipolar transistors in the same conditions but with different bias configurations. We have found that bipolar transistors suffer much more damage when irradiated under unbiased conditions (floating terminals) than when biased during the irradiation. For this reason, unbiased irradiations would largely overestimate the irradiation damage in these devices. Grounding or shorting the devices during irradiation lead to slight more damages, and can be considered worst-case configurations. No irradiation bias effects have been observed for neutron irradiations.

Investigations into the impact of locally modified sensor architectures on the detection efficiency of silicon micro-strip sensors

The High Luminosity Upgrade of the LHC will require the replacement of the Inner Detector of ATLAS with the Inner Tracker (ITk) in order to cope with higher radiation levels and higher track densities. Prototype silicon strip detector modules are currently developed and their performance is studied in both particle test beams and X-ray beams. In previous test beam measurements of prototype modules, the response of silicon sensors has been studied in detailed scans across individual sensor strips. These scans found instances of sensor strips collecting charge across areas on the sensor deviating from the geometrical width of a sensor strip. The variations have been linked to local features of the sensor architecture. This paper presents results of detailed sensor measurements in both X-ray and particle beams investigating the impact of sensor features (metal pads and p-stops) on the sensor strip response.