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Articles you may be interested inInfluence of Ti substitution on the electrical properties of metal-ferroelectric (BiFeO3)-insulator (HfO2)-silicon structures for nonvolatile memory applications The electrical and switching properties of a metal-ferroelectric ( Bi 3.15 Nd 0.85 Ti 3 O 12 ) -insulator ( Y 2 O 3stabilized ZrO 2 )-silicon diode Appl. Phys. Lett. 97, 103501 (2010); 10.1063/1.3486464Characterization of Pt / Bi 3.15 Nd 0.85 Ti 3 O 12 / HfO 2 / Si structure using a hafnium oxide as buffer layer for ferroelectric-gate field effect transistors P-type channel metal-ferroelectric-insulator-silicon field-effect transistors (FETs) with a 300 nm thick SrBi 2 Ta 2 O 9 ferroelectric film and a 10 nm thick HfTaO layer on silicon substrate were fabricated and characterized. The prepared FeFETs were then subjected to 60 Co gamma irradiation in steps of three dose levels. Irradiation-induced degradation on electrical characteristics of the fabricated FeFETs was observed after 1 week annealing at room temperature. The possible irradiation-induced degradation mechanisms were discussed and simulated. All the irradiation experiment results indicated that the stability and reliability of the fabricated FeFETs for nonvolatile memory applications will become uncontrollable under strong irradiation dose and/or long irradiation time. V C 2014 AIP Publishing LLC. [http://dx.

A theoretical model was developed to investigate the ionizing radiation effect on the electrical characteristics of metal-ferroelectric-insulator-semiconductor (MFIS) structure capacitors under exposure to radiation and under post-irradiation conditions. In this model, the radiation-induced degradation in the ferroelectric layer, oxide layer and silicon dioxide interface were considered, and the radiation effect of the silicon substrate was also taken into account to accommodate the dose rate effect. The modeling results showed that both the capacitance versus applied voltage (C-V) curves and the surface potential versus applied voltage (Φ S(Si) -V) curves shifted significantly and the memory window became worse with increasing total dose. Moreover, the derived results indicated that the symmetry of the polarization versus applied voltage (P-V) curves degraded with the increase in total dose, which may explain the phenomena of radiationinduced fatigue and imprint. These results can provide some insights into the estimation of the radiation-induced degradation of MFIS structure devices and may be integrated into electronic design automation (EDA) software for ionizing radiation effect simulation.

Three-dimensional vertical double-gate (FinFET) devices with a high aspect ratio (Si-fin height/width = H fin / W fin = 86 nm/17 nm) and a gate nitrided oxide of 14 Å thickness have been successfully fabricated. Reliability characterizations, including hot-carrier injection (HCI) for NMOS FinFETs and negative bias temperature instability (NBTI) for PMOS FinFETs, are carried out in order to determine their respective lifetimes. The predicted HCI dc lifetime for a 50-nm gate-length NMOS FinFET device at the normal operating voltage (V cc ) of 1.1 V is 133 years. A wider fin-width (27 nm) PMOS FinFET exhibits promising NBTI lifetime such as 26.84 years operating at V cc = −1.1 V, whereas lifetime is degraded for a narrower fin-width (17 nm) device that yields 2.76 years of lifetime at the same operating voltage and stress conditions.Index Terms-FinFET, high aspect ratio, hot-carrier injection (HCI), lifetime, negative bias temperature instability (NBTI), reliability, vertical double-gate MOSFET.

Modeling of the hysteresis loop of ferroelectric thin films has been thought very difficult owing to its nonlinear and history-dependent electric field effects. Here we extend the Preisach model [Z. Phys. 94, 277 (1935)] by using the distribution function integral and superposition method. The model shows improved hysteresis loop that agrees reasonably well with the experimental data measured from the bismuth layer-structured ferroelectric thin films. Compared with the previous model, the current model provides polarization-field (P-E) loop with full and symmetric shape, suitable coercive field (Ec), and few undesirable parameters. The butterfly loop of perovskite-type ferroelectric thin films is also simulated. Additionally, the approach is able to describe the unsaturated loops obtained under various ac electric fields, which is very useful in circuit simulation of ferroelectric field effect transistor or ferroelectric capacitor.