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In this work we investigate the effects of different interface trap density distributions (Dit) on the electrical and power performances of a Gate-All-Around In0.53Ga0.47As/In0.52Al0.48As Nanowire Superlattice-FETs (GAA NW SL-FET) using Al2O3 and HfO2/La2O3 as gate dielectrics. This analysis shows that a high At content at the high-K/InGaAs interface causes degradation of the subthreshold characteristics and drive current, but also an improvement of the OFF-state leakage. However, even in the presence of traps, dynamic energy/power consumption of the Al2O3-based SL-FET is predicted to be at least 2× lower than all the ITRS requirements for the 9nm technology node, while HfO2/La2O3-based device is perfectly suitably for Low-Standby-Power application, at fixed supply voltage Vdd = 0.4 V.

A simulation study on the impact of interface traps (ITs) and strain on the I/V characteristics of co-optimized n- and p-type tunnel field-effect transistors (TFETs) realized on the same InAs/Al 0.05 Ga 0.95 Sb technology platform is carried out using a full-quantum simulator. In order to capture the effect of interface/border traps on the device electrostatics in a way consistent with the ballistic approach, the classical Shockley-Read-Hall theory has been properly generalized. Traps induce a significant reduction on the ON-current; however, the inclusion of a uniform strain induces a remarkable current enhancement able to completely recover the current degradation.

A TCAD-based approach is proposed to investigate the most relevant transport mechanisms of diamond-like carbon (DLC) films at different biases and ambient temperatures. Starting from the band structure and boundary conditions of a metal-insulator-metal (MIM) device, the most relevant trap levels have been determined against experiments along with the Poole-Frenkel conduction effect. The affinity of the DLC under study has been extracted from experiments on the corresponding metal-insulator-semiconductor (MIS) diode. A clear polarization effect has been found in the measured C-V curves at different frequencies. The latter has been modeled in the TCAD tool via the Debye equation leading to a nice agreement with experiments.

Four molding-compound composites with different silica micro-filler size and concentration have been measured on top of dedicated IC test structures. The leakage current of charge sensors has been monitored under different high-voltage stress during charging/discharging transients occurring in the mold. Physical insight of space charge distribution at high electric field and temperature has been obtained by TCAD analysis. The role played by the encapsulation composition on the device-package interaction has been investigated via TCAD simulations of the HTRB test of a Single-RESURF LDMOS.

A 2D TCAD-based approach is proposed to investigate the leakage current and breakdown regime of GaN/AlGaN/Si structures at different ambient temperatures. Deep-level traps originated by Carbon doping, impact-ionization generation and thermally activated Poole-Frenkel conduction have been modeled to assess the role of such physical mechanisms on the forward-bias leakage current. A good agreement with experimental data has been obtained by implementing conduction and valence mini-bands within the deeper transition layer created by conductive dislocation defects or by superlattice structures. A 2D isolation device has been investigated up to breakdown and, for the first time to our knowledge, we prove with 2D TCAD simulation that in GaN based devices both impact-ionization and Poole-Frenkel conduction effects must be taken into account to correctly match experimental data.

The paper reports the radiation response of TFETs due to the gate oxide and BOX separately, by means of the introduction of three setups of bias during irradiation. The dependency of shift of the threshold voltage due to the interface traps and shifts of the characteristics on bias during irradiation is investigated. Due to the particular doping structures of TFETs, the holes trapping in BOX is mainly induced under the P+ source region rather under the channel, which is inclined to induce the increase of the threshold voltage and the voltage at which band-to-band tunneling occurs. Under this circumstance, the degradation under unbiased case is even worse than under ON biased situation.