2013 IEEE International Wireless Symposium (IWS), 2013
ABSTRACT The paper describes the fabrication process, the technology assessment and the experimen... more ABSTRACT The paper describes the fabrication process, the technology assessment and the experimental characterization of silver nanoparticle inkjet-printed microstrip structures on alumina substrates for RF and microwave applications. The present technology allows, through the adoption of innovative silver-based inks and a special piezoelectric-inkjet printer, the direct printing of microstrip prototypes on alumina substrates. The electrical characteristics of the manufactured strips have been modeled, starting from measured data, and several samples of line-stub impedance matching sections have been realized and measured to verify the repeatability of the line characteristic and printing alignment accuracy. More complex structures, including soldered components and ground wrap-around connection, have been realized and tested, showing good agreement between simulations and measurements.
In contemporary society we observe an everlasting permeation of electron devices, smartphones, po... more In contemporary society we observe an everlasting permeation of electron devices, smartphones, portable computing tools. The tiniest living organisms on Earth could become the key to address this challenge: energy generation by bacterial processes from renewable stocks/waste through devices such as microbial fuel cells (MFCs). However, the application of this solution was limited by a moderately low efficiency. We explored the limits, if any, of additive manufacturing (AM) technology to fabricate a fully AM-based powering device, exploiting low density, open porosities able to host the microbes, systems easy to fuel continuously and to run safely. We obtained an optimal energy recovery close to 3 kWh m(-3) per day that can power sensors and low-power appliances, allowing data processing and transmission from remote/harsh environments.
The scaling paradigm known as Moore's Law, with the shrinking of transistors and their do... more The scaling paradigm known as Moore's Law, with the shrinking of transistors and their doubling on a chip every two years, is going to reach a painful end. Another less-known paradigm, the so-called Koomey's Law, stating that the computing efficiency doubles every 1.57 years, poses other important challenges, since the efficiency of rechargeable energy sources is substantially constant, and any other evolution is based on device architecture only. How can we still increase the computational power/reduce the power consumption of our electronic environments? A first answer to this question comes from the quest for new functionalities. Within this aim, negative capacitance (NC) is becoming one of the most intriguing and studied phenomena since it can be exploited for reducing the aforementioned limiting effects in the downscaling of electronic devices. Here we report the evidence of negative capacitance in 80 nm thick ZnO thin films sputtered on Au interdigital electrodes (IDEs). Highly (002)-oriented ZnO thin films, with a fine-grained surface nanostructure and the desired chemical composition, are deposited at room temperature on different IDEs structures. Direct-current electrical measurements highlighted the semiconducting nature of ZnO (current density in the order of 1 × 10(-3) A/cm(2)). When turned into the alternating current regime (from 20 Hz to 2 MHz) the presence of NC values is observed in the low-frequency range (20-120 Hz). The loss of metal/semiconductor interface charge states under forward bias conditions, together with the presence of oxygen vacancies and piezoelectric/electrostriction effects, is believed to be at the basis of the observed negative behavior, suggesting that ZnO thin-film-based field-effect transistors can be a powerful instrument to go beyond the Boltzmann limit and the downscaling of integrated circuit elements required for the fabrication of portable and miniaturized electronic devices, especially for electric household appliances working in the low 50 Hz utility frequency.
... Stefano Bianco, Sanju Gupta, Member, IEEE, Paola Tiberto, Paola Martino, Alessandro Chiolerio... more ... Stefano Bianco, Sanju Gupta, Member, IEEE, Paola Tiberto, Paola Martino, Alessandro Chiolerio, Federica Celegato, Paolo Pandolfi, Alberto Tagliaferro ... Moreover, the island-like Co films morphology will enable the subsequent development of carbon nanotube arrays that may ...
ABSTRACT Acrylic based films containing thermo-chemically synthesized magnetite nanoparticles (NP... more ABSTRACT Acrylic based films containing thermo-chemically synthesized magnetite nanoparticles (NPs) were prepared by UV-curing. A stable dispersion of Fe3O4 NPs in n-hexane was added to polyethylene glycol diacrylate (PEGDA) oligomer or to hexanediol diacrylate (HDDA) oligomer, producing a blend whose viscosity matches the processing requirements for inkjet printing technology. Morphologic characterization is provided by means of Field Effect SEM on a representative nanocomposite section.By real-time FT-IR analysis it was shown that Fe3O4 NPs are able to initiate radical chain-grown polymerization under UV light, for what concerns the HDDA matrix. Tight cross-linked transparent polymeric films were obtained after 1 minute of UV irradiation.The magnetic properties of the produced films were studied by means of an Alternating-Gradient Force Magnetometer (AGFM) in the temperature range 10 – 300 K and up to 18 kOe. The isothermal magnetization curves of both HDDA and PEGDA -based nanocomposites showed that these hybrid systems must be described as interacting superparamagnets (ISP) characterized by inter-particle magnetic interactions dominating over intra-particle effects.
ABSTRACT In this paper, we describe a novel methodology for fabricating conductive epoxy-polythio... more ABSTRACT In this paper, we describe a novel methodology for fabricating conductive epoxy-polythiophene network films by simultaneous photoinduced step-growth and cationic ring opening polymerization processes. For this purpose, formulations containing a bifunctional epoxy monomer, namely 1,6-hexanediol diglycidyl ether (HDGE) and different amount of thiophene ranged from 0 to 50 wt% in the presence of an iodonium salt, namely (4-methylphenyl)[4-(2-methylpropyl) phenyl]-iodonium, hexafluorophosphate were irradiated under UV light. In the process, while polythiophene was formed through electron transfer reaction between photochemically formed phenyliodinium radical cations followed by proton release and coupling reactions, cationic ring opening polymerization of HDGE initiated by the liberated protons resulted in the formation of epoxy network. Conductivity of the obtained films was evaluated by surface resistivity measurements by means of a standard two-point micro-contact method before and after iodine doping. It was found that iodine doping provided a significant improvement in the surface conductivity. This work conclusively provides a new approach for bonding conducting polymers with epoxy-based network films via photoinduced electron transfer reactions in a simple, fast, and efficient approach of importance in electronic and other applications.
... Email: Marco Sangermano (marco.sangermano@polito.it). * Politecnico di Torino, Dipartimento d... more ... Email: Marco Sangermano (marco.sangermano@polito.it). * Politecnico di Torino, Dipartimento di Scienza dei Materiali e Ingegneria Chimica, Corso Duca degli Abruzzi 24, 10125 Torino, Italy. Publication History. ... H. Singh, TA Hatton, GC Rutledge, Polymer 2004, 45, 5505. ...
... Enhanced imaging of magnetic structures in micropatterned arrays of Co dots and antidots. ...... more ... Enhanced imaging of magnetic structures in micropatterned arrays of Co dots and antidots. ... MFM data matrix only undergoes two manipulations in cascade: first, a limited number of scale/histogram normalizations (which correspond to operations on the image colour scale); ...
Magnetization and magnetoresistance of as quenched and joule-heated samples of the ternary alloy ... more Magnetization and magnetoresistance of as quenched and joule-heated samples of the ternary alloy Cu60Fe20Ni20 have been measured at room temperature. Magnetic measurements have been performed up to 700K. All studied samples display magnetic frustration on the nanometer scale; the size of the magnetically correlated regions can be estimated by properly combining magnetization and resistance data. Annealing promotes the magnetoresistive effect
2013 IEEE International Wireless Symposium (IWS), 2013
ABSTRACT The paper describes the fabrication process, the technology assessment and the experimen... more ABSTRACT The paper describes the fabrication process, the technology assessment and the experimental characterization of silver nanoparticle inkjet-printed microstrip structures on alumina substrates for RF and microwave applications. The present technology allows, through the adoption of innovative silver-based inks and a special piezoelectric-inkjet printer, the direct printing of microstrip prototypes on alumina substrates. The electrical characteristics of the manufactured strips have been modeled, starting from measured data, and several samples of line-stub impedance matching sections have been realized and measured to verify the repeatability of the line characteristic and printing alignment accuracy. More complex structures, including soldered components and ground wrap-around connection, have been realized and tested, showing good agreement between simulations and measurements.
In contemporary society we observe an everlasting permeation of electron devices, smartphones, po... more In contemporary society we observe an everlasting permeation of electron devices, smartphones, portable computing tools. The tiniest living organisms on Earth could become the key to address this challenge: energy generation by bacterial processes from renewable stocks/waste through devices such as microbial fuel cells (MFCs). However, the application of this solution was limited by a moderately low efficiency. We explored the limits, if any, of additive manufacturing (AM) technology to fabricate a fully AM-based powering device, exploiting low density, open porosities able to host the microbes, systems easy to fuel continuously and to run safely. We obtained an optimal energy recovery close to 3 kWh m(-3) per day that can power sensors and low-power appliances, allowing data processing and transmission from remote/harsh environments.
The scaling paradigm known as Moore's Law, with the shrinking of transistors and their do... more The scaling paradigm known as Moore's Law, with the shrinking of transistors and their doubling on a chip every two years, is going to reach a painful end. Another less-known paradigm, the so-called Koomey's Law, stating that the computing efficiency doubles every 1.57 years, poses other important challenges, since the efficiency of rechargeable energy sources is substantially constant, and any other evolution is based on device architecture only. How can we still increase the computational power/reduce the power consumption of our electronic environments? A first answer to this question comes from the quest for new functionalities. Within this aim, negative capacitance (NC) is becoming one of the most intriguing and studied phenomena since it can be exploited for reducing the aforementioned limiting effects in the downscaling of electronic devices. Here we report the evidence of negative capacitance in 80 nm thick ZnO thin films sputtered on Au interdigital electrodes (IDEs). Highly (002)-oriented ZnO thin films, with a fine-grained surface nanostructure and the desired chemical composition, are deposited at room temperature on different IDEs structures. Direct-current electrical measurements highlighted the semiconducting nature of ZnO (current density in the order of 1 × 10(-3) A/cm(2)). When turned into the alternating current regime (from 20 Hz to 2 MHz) the presence of NC values is observed in the low-frequency range (20-120 Hz). The loss of metal/semiconductor interface charge states under forward bias conditions, together with the presence of oxygen vacancies and piezoelectric/electrostriction effects, is believed to be at the basis of the observed negative behavior, suggesting that ZnO thin-film-based field-effect transistors can be a powerful instrument to go beyond the Boltzmann limit and the downscaling of integrated circuit elements required for the fabrication of portable and miniaturized electronic devices, especially for electric household appliances working in the low 50 Hz utility frequency.
... Stefano Bianco, Sanju Gupta, Member, IEEE, Paola Tiberto, Paola Martino, Alessandro Chiolerio... more ... Stefano Bianco, Sanju Gupta, Member, IEEE, Paola Tiberto, Paola Martino, Alessandro Chiolerio, Federica Celegato, Paolo Pandolfi, Alberto Tagliaferro ... Moreover, the island-like Co films morphology will enable the subsequent development of carbon nanotube arrays that may ...
ABSTRACT Acrylic based films containing thermo-chemically synthesized magnetite nanoparticles (NP... more ABSTRACT Acrylic based films containing thermo-chemically synthesized magnetite nanoparticles (NPs) were prepared by UV-curing. A stable dispersion of Fe3O4 NPs in n-hexane was added to polyethylene glycol diacrylate (PEGDA) oligomer or to hexanediol diacrylate (HDDA) oligomer, producing a blend whose viscosity matches the processing requirements for inkjet printing technology. Morphologic characterization is provided by means of Field Effect SEM on a representative nanocomposite section.By real-time FT-IR analysis it was shown that Fe3O4 NPs are able to initiate radical chain-grown polymerization under UV light, for what concerns the HDDA matrix. Tight cross-linked transparent polymeric films were obtained after 1 minute of UV irradiation.The magnetic properties of the produced films were studied by means of an Alternating-Gradient Force Magnetometer (AGFM) in the temperature range 10 – 300 K and up to 18 kOe. The isothermal magnetization curves of both HDDA and PEGDA -based nanocomposites showed that these hybrid systems must be described as interacting superparamagnets (ISP) characterized by inter-particle magnetic interactions dominating over intra-particle effects.
ABSTRACT In this paper, we describe a novel methodology for fabricating conductive epoxy-polythio... more ABSTRACT In this paper, we describe a novel methodology for fabricating conductive epoxy-polythiophene network films by simultaneous photoinduced step-growth and cationic ring opening polymerization processes. For this purpose, formulations containing a bifunctional epoxy monomer, namely 1,6-hexanediol diglycidyl ether (HDGE) and different amount of thiophene ranged from 0 to 50 wt% in the presence of an iodonium salt, namely (4-methylphenyl)[4-(2-methylpropyl) phenyl]-iodonium, hexafluorophosphate were irradiated under UV light. In the process, while polythiophene was formed through electron transfer reaction between photochemically formed phenyliodinium radical cations followed by proton release and coupling reactions, cationic ring opening polymerization of HDGE initiated by the liberated protons resulted in the formation of epoxy network. Conductivity of the obtained films was evaluated by surface resistivity measurements by means of a standard two-point micro-contact method before and after iodine doping. It was found that iodine doping provided a significant improvement in the surface conductivity. This work conclusively provides a new approach for bonding conducting polymers with epoxy-based network films via photoinduced electron transfer reactions in a simple, fast, and efficient approach of importance in electronic and other applications.
... Email: Marco Sangermano (marco.sangermano@polito.it). * Politecnico di Torino, Dipartimento d... more ... Email: Marco Sangermano (marco.sangermano@polito.it). * Politecnico di Torino, Dipartimento di Scienza dei Materiali e Ingegneria Chimica, Corso Duca degli Abruzzi 24, 10125 Torino, Italy. Publication History. ... H. Singh, TA Hatton, GC Rutledge, Polymer 2004, 45, 5505. ...
... Enhanced imaging of magnetic structures in micropatterned arrays of Co dots and antidots. ...... more ... Enhanced imaging of magnetic structures in micropatterned arrays of Co dots and antidots. ... MFM data matrix only undergoes two manipulations in cascade: first, a limited number of scale/histogram normalizations (which correspond to operations on the image colour scale); ...
Magnetization and magnetoresistance of as quenched and joule-heated samples of the ternary alloy ... more Magnetization and magnetoresistance of as quenched and joule-heated samples of the ternary alloy Cu60Fe20Ni20 have been measured at room temperature. Magnetic measurements have been performed up to 700K. All studied samples display magnetic frustration on the nanometer scale; the size of the magnetically correlated regions can be estimated by properly combining magnetization and resistance data. Annealing promotes the magnetoresistive effect
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