Jo sóc armat. Reivindicant la identitat cristiana i local

En este artículo nos proponemos analizar las motivaciones de un grupode participantes de las procesiones de Semana Santa conocidos como los “armats” deuna población de la costa catalana. Esta cofradía está formada por un grupo de unostreinta hombres. Van caracterizados com si fueran soldados romanos y acompañana la figura de Jesucristo en las procesiones que rememoran su muerte. La identidadfuerte del grupo, conseguida a partir de un funcionamiento ritualizado, consolidauna práctica de origen religioso en un contexto de reencantamiento de la vida, demultiplicidad de prácticas religiosas, del uso moderno de la tradición y de la reivindicaciónde la localidad en un momento de cambios fruto de la globalización

Temperature-dependent transition to progressive breakdown in thin silicon dioxide based gate dielectrics

The transition between well-defined soft and hard breakdown modes to progressive breakdown in ultrathin silicon dioxide based dielectrics is studied by means of the statistics of residual time (the time from first breakdown to device failure). By stressing metal-oxide-semiconductor test capacitors with an oxide thickness of 2.2nm under different gate bias and temperatures, it is demonstrated that low voltages and temperatures favor stable hard and soft breakdown modes, while high temperatures and voltages lead to a progressive breakdown controlled regime. Our results support the idea that no significant change of the involved physics occurs in the transition from one breakdown regime to the other. The continuous transition from one regime to the other permits one to clearly identify progressive breakdown as hard breakdown, which always requires a certain time to reach the device failure conditions

Mesoscopic approach to the soft breakdown failure mode in ultrathin SiO2 films

We present an analytic model for the soft breakdown failure mode in ultrathin SiO2 films based on the conduction theory through quantum point contacts. The breakdown path across the oxide is represented by a three-dimensional constriction in which, due to the lateral confinement of the electron wave functions, discrete transverse energy levels arise. In the longitudinal direction, such levels are viewed by the incoming electrons as effective potential barriers, which can be treated using the one-dimensional tunneling formalism. In addition, it is shown that our mesoscopic approach is also consistent with the hard breakdown conduction mode

Hydrogen release mechanisms in the breakdown of thin SiO2 films

The mechanism of hydrogen release from the anode Si/SiO2 interface that triggers defect generation and finally the dielectric breakdown of the oxide in metal-oxide-semiconductor structures is investigated. Extensive experimental charge-to-breakdown statistics are used to derive the defect generation efficiency as a function of gate voltage and oxide thickness in wide ranges. The presented results provide strong support to single-electron assisted Si-H bond breakage and discard multiple electron induced incoherent vibrational heating mechanisms

Multi-terminal transistor-like devices based on strongly correlated metallic oxides for neuromorphic applications

Memristive devices are attracting a great attention for memory, logic, neural networks, and sensing applications due to their simple structure, high density integration, low-power consumption, and fast operation. In particular, multi-terminal structures controlled by active gates, able to process and manipulate information in parallel, would certainly provide novel concepts for neuromorphic systems. In this way, transistor-based synaptic devices may be designed, where the synaptic weight in the postsynaptic membrane is encoded in a source-drain channel and modified by presynaptic terminals (gates). In this work, we show the potential of reversible field-induced metal-insulator transition (MIT) in strongly correlated metallic oxides for the design of robust and flexible multi-terminal memristive transistor-like devices. We have studied different structures patterned on YBa2Cu3O7−δ films, which are able to display gate modulable non-volatile volume MIT, driven by field-induced oxygen diffusion within the system. The key advantage of these materials is the possibility to homogeneously tune the oxygen diffusion not only in a confined filament or interface, as observed in widely explored binary and complex oxides, but also in the whole material volume. Another important advantage of correlated oxides with respect to devices based on conducting filaments is the significant reduction of cycle-to-cycle and device-to-device variations. In this work, we show several device configurations in which the lateral conduction between a drain-source channel (synaptic weight) is effectively controlled by active gate-tunable volume resistance changes, thus providing the basis for the design of robust and flexible transistor-based artificial synapses