Drain-source current in organic thin-film transistors has been monitored in situ and in real time during the deposition of pentacene. The current starts to flow when percolation of the first monolayer (ML) occurs and, depending on the deposition rate, saturates at a coverage in the range 2-7 MLs. The number of active layers contributing to the current and the spatial distribution of charge carriers are modulated by the growth mode. The thickness of the accumulation layer, represented by an effective Debye length, scales as the morphological correlation length. These results show that the effective Debye length is not just a material parameter, but depends on the multiscale morphology. Earlier controversial results can be unified within this framework.

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The enabling technologies for the development of a flexible tag microlab for food monitoring during the logistic chain will be presented. The realisation of the system includes the integration of physical and chemical sensors with Radio Frequency IDentification (RFID) communication capabilities. The first ISO 15693 compliant semi-active tag prototype, including low power control electronics, RFID antenna, commercial sensors, memory and a thin film battery, is shown together with the development of novel ultra-low power hotplates required for this application and the process, based on the use of anisotropic conductive adhesive (ACA) flip chip technology, for gas sensors integration onto flexible substrates.

We have measured the radiation tolerance of poly-crystalline and single-crystalline diamonds grown by the chemical vapor deposition (CVD) process by measuring the charge collected before and after irradiation in a 50 m pitch strip detector fabricated on each diamond sample. We irradiated one group of sensors with 800 MeV protons, and a second group of sensors with 24 GeV protons, in steps, to protons cm−2 and protons cm−2 respectively. We observe the sum of mean drift paths for electrons and holes for both poly-crystalline CVD diamond and single-crystalline CVD diamond decreases with irradiation fluence from its initial value according to a simple damage curve characterized by a damage constant for each irradiation energy and the irradiation fluence. We find for each irradiation energy the damage constant, for poly-crystalline CVD diamond to be the same within statistical errors as the damage constant for single-crystalline CVD diamond. We find the damage constant for diamond irradiated with 24 GeV protons to be and the damage constant for diamond irradiated with 800 MeV protons to be . Moreover, we observe the pulse height decreases with fluence for poly-crystalline CVD material and within statistical errors does not change with fluence for single-crystalline CVD material for both 24 GeV proton irradiation and 800 MeV proton irradiation. Finally, we have measured the uniformity of each sample as a function of fluence and observed that for poly-crystalline CVD diamond the samples become more uniform with fluence while for single-crystalline CVD diamond the uniformity does not change with fluence.

Electromigration phenomena in metallic lines are studied by using a biased resistor network model. The void formation induced by the electron wind is simulated by a stochastic process of resistor breaking, while the growth of mechanical stress inside the line is described by an antagonist process of recovery of the broken resistors. The model accounts for the existence of temperature gradients due to current crowding and Joule heating. Alloying effects are also accounted for. Monte Carlo simulations allow the study within a unified theoretical framework of a variety of relevant features related to the electromigration. The predictions of the model are in excellent agreement with the experiments and in particular with the degradation towards electrical breakdown of stressed Al-Cu thin metallic lines. Detailed investigations refer to the damage pattern, the distribution of the times to failure (TTFs), the generalized Black's law, the time evolution of the resistance, including the early-stage change due to alloying effects and the electromigration saturation appearing at low current densities or for short line lengths. The dependence of the TTFs on the length and width of the metallic line is also well reproduced. Finally, the model successfully describes the resistance noise properties under steady state conditions.