POLITECNICO DI BARI
Dipartimento di Elettrotecnica ed Elettronica
1. DESIGN, FABRICATION AND CHARACTERIZATION OF OPTOELECTRONIC AND PHOTONIC DEVICES
M.N. Armenise, C. Ciminelli, F. Dell’Olio, C.E. Campanella, C.M. Campanella, N. Sasanelli
Collaborations: University of Glasgow; Opto-electronics section at the European Space Agency; Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut; Optical Characterization and Nanophotonics Laboratory, Boston University; Thales Alenia Space, Italy; Selex Sistemi Integrati; Centre for Integrated Photonics; Department of Information Science and Electronic Engineering, Zhejiang University; IIT Lecce; Technische Universität Wien; Università di Cagliari; Università di Napoli Federico II; Dipartimento di Chimica, Università di Bari.
2. TESTING, CHARACTERIZATION AND DESIGN OF SILICON DEVICES AND ICS
Collaborations: INFN Sez. di Bari e Pisa, CERN, Fbk-IRST, Brookhaven National Labs (USA)
3. DESIGN AND TEST OF ELECTRONIC INTEGRATED SYSTEMS: SENSORS AND INTERFACES
D. De Venuto
Collaborations: University of California at Berkeley, École Polytechnique Fédérale de Lausanne EPFL,Switzerland, IMEC Leuven, Belgium, NXP Semiconductors Eindhoven, The Netherlands, CNR, CNRS, IIT.
4. DESIGN OF AN ELECTRONIC MEDICAL DEVICE for ventricular late potentials detection
Collaborations: Università degli Studi di Bari
DESIGN, FABRICATION AND CHARACTERIZATION OF OPTOELECTRONIC AND PHOTONIC DEVICES
M.N. Armenise, C. Ciminelli, F. Dell’Olio, C.E. Campanella, C.M. Campanella, N. Sasanelli
Research activity of the Optoelectronics Laboratory is focused on modeling, design, fabrication, and characterization of active and passive integrated optical and optoelectronic devices, including photonic crystal-based devices, electro-optic, acousto-optic, and magneto-optic devices, dielectric waveguides, and components in semiconductor and ferroelectric materials. In particular the main research topics are:
I. Design of photonic devices for sensing and telecom applications. Guided-wave components have been studied and proposed in innovative architectures for filtering in DWDM applications, including grating-assisted vertical directional couplers and multi-frequency acousto-optic Bragg cells. Research efforts are focusing on the study of optical resonators for sensing applications.
Modelling and design techniques have been developed for optimizing the performance of a number of guided-wave optical sensors for gyroscope systems, considering both ring laser-based and passive ring resonator. Integrated optical architectures with very high sensitivity have been modelled, designed and simulated to be used in space applications. Physical effects and technological aspects have been taken into account. Prototypes of different configurations of the angular velocity sensor based on the passive ring resonator structure have been fabricated and tested showing a sensitivity of about 10 °/h. Design, optimization and fabrication of fully integrated angular velocity photonic sensors based on InP ring resonators are ongoing, together with the study of new configurations both based on coupled cavities exploiting the slow light effect and photonic crystals cavities.
Optical resonators, with different geometrical configurations such as ring, disk, sphere or Fabry-Perot, have a resonant response that can be strongly dependent on the refractive index of a specific part of the resonator geometry. Investigations are devoted to the study of devices to be used for revealing the presence of specific chemical elements. A prototype of a chemical sensor has been fabricated and characterized. Research activities concerning the detection and sizing of toxic nanoparticles and viruses have been developed. The interaction between a whispering gallery mode optical microresonator and nanoparticles has been modeled by employing the scattering laws and quantum electrodynamic principles in order to get an analytical formula of nanoparticles radius, by assuming an a priori knowledge of nanoparticle nature (i.e. shape and refractive index).
A new nanophotonic plasmon hollow light-guiding structure which is also an efficient microfluidic channel has been proposed and accurately modeled. We proved that the waveguide has a wide range of applications, especially in the field of gas sensing.
Innovative configurations of electric field integrated optical sensors are currently under development in the framework of a project founded by MIUR. The sensor allows the contextual measurement of two field components and it is very useful to improve the near-field characterization of radiating systems, such as antennas for radar or space applications. A channel waveguide to be realized by titanium thermal diffusion in lithium niobate has been optimized for the sensor fabrication.
II. Modelling and design of active optoelectronic devices. This activity includes the study of suitable models and the design of active devices such as semiconductor optical amplifier (SOA) and semiconductor lasers. Design of a InP based DFB laser, with specific reference to the issues derived from the integration with passive devices is ongoing.
III. Modelling, design, fabrication, and testing of photonic crystal devices. A new model based on Green's functions has been developed for analyzing wave propagation in 2D photonic bandgap nanocavities to determine both band diagrams and electromagnetic field distributions when the structure under investigation is illuminated by an external source, either a Hankel source or a plane wave coming from infinite distance. Numerical results have been compared with those obtained using other well-known methods, showing some significant advantages mainly in terms of CPU time without any loss of accuracy. The study and the design of novel nanoplasmonic cavities based on a 1D PhC are ongoing.
IV. Modelling, design, and optimization of optical data links for on-board data handling. An innovative high speed fiber optic data link has been modeled and designed. The system has been optimized to be included in a new complex processing architecture for SAR (Synthetic-Aperture Radar) applications that is under development at Thales Alenia Space-Italy in the framework of an ASI (Italian Space Agency) co-funded project.
1) C. Ciminelli, F. Dell’Olio, C.E. Campanella, M.N. Armenise, “Sub-micrometer plasmon hollow waveguides for chemical sensing applications”, Proc. of the 4th EOS Topical Meeting on Optical Microsystems (OμS’11), Capri (Na), 26-28 September 2011, pp. 107-108. (ISBN: 978-1-61839-481-1)
2) C. Ciminelli, F. Dell’Olio, M.N. Armenise, “Integrated optical sensor array for measuring amplitude and phase of electric fields in radiating systems”, Proc. of the 4th EOS Topical Meeting on Optical Microsystems (OμS’11), Capri (Na), 26-28 September 2011, pp. 39-40. (ISBN: 978-1-61839-481-1)
3) C. Ciminelli, F. Dell’Olio, M.N. Armenise, “Accurate Dynamic Model of DFB lasers”, Proc. of the 11th International Conference on Numerical Simulation of Optoelectronic Devices, Roma, 5-8 September 2011, paper MPD6, postdeadline paper. (ISBN 978-1-61284-877-8)
4) C. Ciminelli, F. Dell’Olio, C.E Campanella, M.N. Armenise, “Innovative integrated-optic resonator for angular rate sensing: design, fabrication and characterization,” in Sensors and Microsystems - AISEM 2010 proceedings, G. Neri et al., Eds. (Springer, 2011, ISBN 978-94-007-1323-9).
5) C. Ciminelli, C.M. Campanella, M.N. Armenise, “Design, Fabrication and Characterization of a New Hybrid Resonator for Biosensing Applications,” in Sensors and Microsystems - AISEM 2010 proceedings, G. Neri et al., Eds. (Springer, 2011, ISBN 978-94-007-1323-9).
6) C. Ciminelli, C.M. Campanella, M.N. Armenise, “Hybrid optical resonator for nanostructured virus detection and sizing”, Proc. of IEEE International Workshop on Medical Measurements and Applications Proceedings (MeMeA), 2011.
7) C. Ciminelli, C.M. Campanella, R. Pilolli, N. Cioffi, M.N. Armenise, “Optical sensor for nanoparticles”, Proc. of 13th International Conference on Transparent Optical Networks (ICTON), 2011. INVITED PAPER.
8) M.N. Armenise, C. Ciminelli, F. Dell'Olio, V.M.N. Passaro, “Advances in Gyroscope Technologies”, Springer Ed. Pub., 2011.
9) C. Ciminelli, “Introduction to photonic crystals and metamaterials”, «Selected topics on metamaterials and photonic crystals», World Scientific Edit., 2011. (Invited)
10) C. Ciminelli, C.M. Campanella, M.N. Armenise, “Hybrid Ring-Resonator Optical Systems for Nanoparticle Detection and Biosensing Applications,” in Sensors and Microsystems – AISEM 2011 proceedings, A. D’amico et al., Eds. (Springer, 2012, ISBN 978-1461409342).
TESTING, CHARACTERIZATION AND DESIGN OF SILICON DEVICES AND ICS
A. ICs for High Energy Physics and Medical Imaging applications.
A gamma-ray imaging system for medical applications with good spatial resolution and image contrast has been designed within the framework of a PRIN project. The system is aimed to an application in the field of the molecular imaging and scintimammography and is based on a two-dimensional array of silicon PIN photodiodes equipped with a scintillator layer of inorganic material (CsI). The specific activity of the Bari unit has been devoted to the design of the detector front-end electronics, whose structure consists in low-noise charge preamplifier or "charge sensitive amplifier" (CSA) followed by a "slow" shaper filter that reduces noise. Innovative solutions have been adopted for some building blocks of the circuits, such as, for instance, the baseline holder which sets the DC output level of the shaper.
Another research line is related to the design of front-end electronics for Silicon Photomultiplier detectors (SiPM), in the framework of a V Group INFN project called DaSiPM. A first integrated prototype of the analog front-end channel, based on a current buffer structure and suitable to accomodate the large dynamic range and high speed carachteristics of the signal delivered by a SiPM, has been produced in a standard CMOS 0.35µm technology. The results of the front-end characterization show that the linearity of the chip is very good and therefore the proposed solution can be adopted in applications ranging from medical imaging to high energy physics. Based on this analogue front-end chain, an 8-channel ASIC has been designed and manufactured in a 0.35um CMOS process. The ASIC is intended to be used to read-out SiPM matrices or arrays to be employed in medical imaging applications. It encloses an ADC, taken from an analog library, a fast-OR circuit and a standard cell digital part, which implements different read-out procedures and allows to configure the analogue channels. The experimental characterization of the 8-channel ASIC proved the capability of the chip to correctly process the charge delivered by the detectors in response to an event and the accuracy in the extraction of the timing information of both single and multiple events, to be used, for instance, for subsequent coincidence analysis. A further 32-channel prototype of the front-end chip has then been designed and manufactured in the same 0.35um CMOS process. The ASIC includes some improvements in the fast-OR circuit and the ADC which has been ad-hoc designed to meet the speed requirements of different applications. The characterization of the 32-channel ASIC is currently in progress.
B. Design of low-voltage CMOS analog integrated structures.
In collaboration with different european companies, the study of analog basic building blocks for low-voltage CMOS integrated circuits has been carried out. Basically the considered structures are single low-distorsion OTAs to be inserted in analog filters for VDSL applications and high-gain OPAMP to be employed in fast and accurate ADCs. Also new structures for current mirrors intended for low voltage applications have been proposed, which are characterized by very good performance in terms of output resistance and compliance.
1) C. Marzocca, G. Matarrese, F. Corsi (2011). Design and characterization of a 32-channel front-end ASIC for Silicon Photo- Multiplier detectors. In: Proceedings of 4th IEEE Workshop on Advances in Sensors and Interfaces. Savelletri (Br), 28-29 giugno 2011
2) F. Corsi, C. Marzocca, G. Matarrese (2011). Amplificatore in transimpedenza per fotorivelatori. In: Elettronica Analogica. MILANO:The McGraw-Hill Companies, ISBN: 978-88-386-8740-2
3) F. Corsi, C. Marzocca, G. Matarrese (2011). Amplificatore cascode ripiegato. In: Elettronica Analogica. Milano:Mc-Graw Hill, ISBN: 978-88-386-8740-2
4) S. Marcatili, N. Belcari, M.G. Bisogni, G. Collazuol, G. Ambrosi, F. Corsi, M. Foresta, C. Marzocca, G. Matarrese, G. Sportelli, P. Guerra, A. Santos, A. Del Guerra (2011). Development and characterization of a modular acquisition system for a 4D PET block detector. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT, vol. A659, p. 494-498, ISSN: 0168-9002, doi: 10.1016/j.nima.2011.08.042
5) A. Argentieri, F. Corsi, M. Foresta, C. Marzocca, A. Del Guerra (2011). Design and characterization of CMOS multichannel front-end electronics for silicon photomultipliers. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT, ISSN: 0168-9002, doi: 10.1016/j.nima.2010.08.067
6) S. Marcatili, N. Belcari, M.G. Bisogni, G. Collazuol, G. Sportelli, E. Pedreschi, F. Spinella, M. Foresta, C. Marzocca, A. Del Guerra, (2011). A small animal PET prototype based on Silicon Photomultipliers. IL NUOVO CIMENTO C, vol. 34, p. 3-10, ISSN: 2037-4909
7) F. Ciciriello, F. Corsi, F. Licciulli, C. Marzocca, G. Matarrese (2011). Assessing the Time Resolution of an Integrated Fornt-End for Solid State Radiation Detectors. In: Nuclear Science Symposium Conference Record (NSS/MIC) 2011. Valencia, 23-29 Ottobre 2011, p. 1678-1682, ISBN: 978-1-4673-0119-0
8) M. Morrocchi, S. Marcatili, . Belcari, M. G. Bisogni, G. Collazuol, G. Ambrosi, F. Corsi, M. Foresta, Marzocca C, G. Matarrese, G. Sportelli, P.Guerra, A. Santos, A. Del Guerra (2011). Characterization and Test of a Data Aquisition System for PET. In: Nuclear Science Symposium Conference Record (NSS/MIC). Valencia, 23-29 Ottobre 2011, p. 621-625, ISBN: 978-1-4673-0119-0
9) G. De Luca, M.G. Bisogni, G. Collazuol, A. Argentieri, F. Corsi, Marzocca C, C. Piemonte, A. Del Guerra (2011). Signal Shape of a PET Detector based on LSO:Ce,Ca Crystals and SiPM. In: Nuclear Science Symposium Conference Record (NSS/MIC). Valencia , 23-29 Ottobre 2011, p. 613-616, ISBN: 978-1-4673-0119-0
10) P. Musico, L. Cosentino, F. Corsi, F. Cusanno, R. De Leo, P. Finocchiaro, A. Gabrielli, F. Garibaldi, F. Giorgi, F. Giuliani, M. Gricia, F. Licciulli, F. Loddo, M. Lucentini, Marzocca C, F. Meddi, E. Monno, A. Pappalardo, R. Perrino, A. Ranieri, M. Turisini (2011). The electronic system for a TOF PET prostate probe . In: Nuclear Science Symposium Conference Record (NSS/MIC) 2011. Valencia, 23-29 Ottobre 2011, p. 2436-2438, ISBN: 978-1-4673-0119-0
DESIGN AND TEST OF ELECTRONIC INTEGRATED SYSTEMS: SENSORS AND INTERFACES
D. De Venuto
A. Integrated sensors for perishables monitoring with RFID
Radio Frequency Identification (RFID) is a booming technology mainly used as replacement of barcodes, especially the last two years .[1-4] A majority of large groups and multinationals have already assessed the implementation of the technology. Nevertheless, few companies did adopt it. Indeed, according to  its cost remains a big issue for all organizations as the return on investment is rather difficult to predict in most cases. There are two options to stimulate the use of RFID: reduce the costs even further or add features that bring additional value. A decrease of the tag cost is what has been explored the most so far. It will have to go down to a price close to the barcode to become attractive for the users.
Additional functionality is inherently the largest differentiator for such a high-tech product as RFID from printed barcodes and it is of no surprise that security, active functionality, sensors are additional functionalities required by the potential customers. For instance, in a case or pallet-level tagging the addition of RFID tags will allow the players in the supply chain to follow up the shipments and more easily verify their orders. The introduction of sensor-enabled RFID tags will bring another dimension to supply chain of perishable products (as fresh produce, beverages and medical supplies): quality monitoring. Addition of various environmental sensors allows to keep track of relevant parameters such as temperature, light intensity, humidity, pH, gas compositions (in products with modified atmosphere packages). Such an integrated RFID+sensors system provides both information about the origin of the product and the conditions under which it has been transported, processed and stored. The end result is a history of the parameters monitored that can be used as decision making instruments in terms of acceptable quality.
Enabling such a product, however, requires unprecedented efforts in reducing the power consumption of each building block since the available power is very limited (in a typical use case, a 2mW.h battery is used for ~1500 sensing and logging events) requiring operation of a typical AD converter in uW range. The research activity in this area carried on by the Bari Team is devoted to design a low power readout electronic for the autonomous sensors system.
B. Biosignal sensing for brain-machine interface
Fast and efficient development of the various components of the neuro-BSN requires the development of novel designs and methods. From the brain-interface viewpoint, new sensor devices must be designed to meet the requirements of high signal-to-noise and stability as well as to deliver long-run and accurate monitoring needed by signal recognition algorithms in pathology characterization. Furthermore, to enhance the precision of brain monitoring, the requirement in term of the number of signal to be acquired is likely to increase for future generation brain disorder monitoring applications. In particular, the design of new electrode arrays for capturing brain electrical signals wirelessly connected to the wearable signal processing platform must be studied. Despite the availability of many commercial products, electrode-skin interface optimization and the low-noise and long term stability requirements are far from being solved. The design of new custom sensor requires in particular a rethinking of the front-end, to specifically address the difficulties with achieving a very high input impedance amplifier and to match the stringent power requirements. As such, the design of the acquisition subsystem will address an innovative ultra low-power analog-to-digital front-end for autonomous multi-sensing. To achieve the targeted autonomy of the sensing subsystem and provide the needed accuracy, the design of the acquisition/sampling section must be inspired by a new paradigm, able to optimize the number of measurements for the correct signal reconstruction with respect to the real amount of information of the signal. Since EEG signals are known to carry an information rate much less than what suggested by their bandwidth, in this project Compressed Sensing techniques will be adopted to reduce the amount of resources (and thus power) needed for the A/D conversion with respect to standard sampling. By reducing the sampling rate, the transmission rates from the sensing subsystem to the central processing platform will be also optimized, with a positive impact on real-time performance and power consumption. Once the data are digitized and transmitted to the wearable processing platform, heavy processing algorithms must be applied concerning filtering, knowledge extraction and reasoning. To meet the 1pj per operation target, which would enable an unprecedented autonomy for this class of ubiquitous computing platforms, the design of an ultra-energy-efficient heterogeneous multi-core platform must be addressed. An additional subordinate objective of this project is the design of a new class of programmable parallel architectures equipped with integrated non-volatile memory optimized for near-threshold CMOS implementation, with extensive design automation support for variability tolerance, self-repair and aggressive energy management.
1) D. De Venuto, S. Carrara, B. Riccò: “High Resolution Electronics for Label free Capacitive DNA detection” in Sequence and Genome Analysis: Methods and Applications, Gabriel Fung, iConcept Ed. USA 2011 ISBN: 978-0980733051 (Hard Cover) / 978-1463789138 (Paperback)
2) D. De Venuto, S. Carrara, G. De Micheli: “pH sensing with temperature compensation in a Molecular Biosensor for Drugs Detection” Proc. Of The 12th IEEE International Symposium on Quality Electronic Design, Santa Clara, CA 14-16 March 2011.
3) D. De Venuto, E. Stikvoort: “ Low Power Smart Sensor for Accurate Temperature Measurements” Proc. Of 4th IEEE International Workshop on Advances in Sensors and Interfaces IWASI2011, June 28-29 2011 Savelletri di Fasano (Brindisi) Italy.
DESIGN OF AN ELECTRONIC MEDICAL DEVICE for ventricular late potentials detection
The ventricular late potentials (VLP) are high frequency (in relation to the bandwidth of the electrocardiographic signal) and very low intensity signals. The presence of VLPs in the electrocardiographic signal has been associated with damages in the ventricular myocardial tissues. The necrosis or ischemic death of myocardial cells causes the formation of high resistivity areas, where the propagation of cardiac action potential is delayed. This phenomenon affects the electrocardiographic signal with the presence of electrical activity, although of low intensity, between the end of the QRS complex and the initial part of the ST segment, where it should not be.
VLPs are localized at the end of QRS complex and in the initial part of the ST segment. Their intensity is at least two orders of magnitude smaller than the electrocardiographic signal, so they are usually "hidden" below the noise produced by the acquisition hardware and the electrical activity not related to the heart. For this reasons VLPs are not easily visible on the ECG.
Several statistical studies demonstrated a correlation between the presence of VLPs and the possibility of sudden cardiac death due to arrhythmia, often tachycardia. Patients with previous ischemic events are the most at risk. A correct VLPs detection makes the prevention of this serious malignant arrhythmias possible.
A classic electrocardiographic signal has amplitude of the order of a few mV and it contains most of the information at frequencies below 100 Hz. VLPs, if present, are considered non-stationary and non-gaussian signals with an amplitude between 1 and 20 µV.
The low amplitude and high frequency dispersion makes VLPs detection very difficult, often the signal is dominated by the noise. It is therefore necessary to process the signal to drastically reduce the noise level.
The research activity developed aimed to propose a method to detect VLPs in two different conditions: analyzing a few minutes of prerecorded ECG with the use of Signal Averaged Electrocardiography (SAECG), and examining the ECG during its acquisition for real-time diagnostic applications. The first analysis allows the identification of weaker VLPs, while the second can be used for real-time diagnostic purposes.
Another technique of denoising, the wavelet denoising, was used in order to obtain a better detection and to optimize the real time analysis. The simultaneous use of wavelet denoising and SAECG, in post-acquisition processing, yielded good results also with short-term ECG. However, the most innovative feature of the research activity regards the search for parameters, in the time-frequency domain, that confer robustness to the method, as the introduction of a parameter not influenced from the J point location (ENend). Finally, a bivariable separation between the time-frequency parameters improved the effectiveness of the method.
Despite VLP can be of great importance in the arrhythmic risk prevention, their detection is not yet widespread, due to the lack of suitable equipment. Our work is an attempt to solve this problem by providing a robust and reliable algorithm.
1) GIORGIO A (2011). ICT for telemedicine and health care innovation. RECENT PATENTS ON BIOMEDICAL ENGINEERING, vol. 4 n. 2, ISSN: 1874-7647
2) GIORGIO A (2011). Innovative medical devices for telemedicine applications. In: IN TECH WEB ED.. Telemedicine techniques and applications. In tech, ISBN: 979-953-307-008-6
3) GIORGIO A (2011). Dispositivo medico per il telemonitoraggio e la diagnosi di patologie psicosomatiche. In: Aitim 2011. Bologna, 30-31 maggio 2011