The effects of heavy-ion test conditions and beam energy on device response are investigated. These effects are illustrated with two types of test vehicles; SRAMs and power MOSFETs. In addition, GEANT4 simulations have also been performed to better understand the results

The main em phasis of this study is the investigation of the gate degradation or rupture, aiming to determine the nature of the so-called SEGR phenomena. This article presents experimental data showing heavy ions induced gate degradation in power MOSFETs. In the experiments, backside and front-side irradiations are performed. The heavy ions ranges are tuned in such way to control whether they hit the gate or not, during backside irradiation. Gate-to-source current Igss (4)) is measured versus Heavy Ions (H.I.) fluence 4>. Post-irradiation-Gate-StressTest (PGST) allows to measure breakdown voltage VBD(4)) as being decreasing with (H.I.) fluence. Based on these experimental results, an hypothesis of substrate-generated "hot carriers" impact overlap may explain gate degradation until SEGR triggering. This last hypothesis is supported by statistical approach model of heavy ions multiple impact.

No abstract

<div> <div> <div> <p>The use of ionic liquid-based colloids at elevated temperatures is one of their most promising fields of application. However long term stability on the whole range of temperature is mandatory. First a detailed study on colloidal dispersions of iron oxide nanoparticles in EMIM TFSI is performed at room temperature in order to determine the best solid/liquid interface. The previously identified key parameters are tuned: the surface charge density and the nature of the counterions. Here a sulfonate based imidazolium ion is chosen. In a second step, the thermal stability of these nanoparticle dispersions is analysed on the short and long term up to 473 K (200◦C) combining dynamic light scattering (DLS), small angle X-ray/neutron scattering (SAXS/SANS) and thermogravimetric analysis (TGA). Ionic liquid-based colloidal dispersions of iron oxide nanoparticles in EMIM TFSI stable in the long term can be obtained at least up to 473 K and nanoparticle concentrations of 12 vol% (≈30wt%) </p> </div> </div> </div>