Tyndall National Institute - Book Chapters

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Mesoporous materials as templates for semiconductor nanowires assembly
(IOS Press, 2003) Holmes, Justin D.; Morris, Michael A.; Ryan, Kevin M.; European Commission; Intel Corporation; Intel Ireland Ltd.
In this chapter is described a novel approach for synthesizing mesoporous silicas with tunable pore diameters, wall thickness and pore spacings that can be used as templates for the assembly of semiconductor nanowire arrays. Silicon and germanium nanowires, with size monodisperse diameters, can readily be formed within the mesoporous silica matrix using a supercritical fluid inclusion technique. These nano-composite materials display unique optical properties such as intense room temperature ultraviolet and visible photoluminescence. The implication of these mesoporous nanowire materials for future electronic and opto-electronic devices is discussed.
Probing of nanocontacts inside a transmission electron microscope
(Springer-Verlag Berlin Heidelberg, 2007) Erts, Donats; Lohmus, Ants; Holmes, Justin D.; Olin, Hakan
In the past twenty years, powerful tools such as atomic force microscopy have made it possible to accurately investigate the phenomena of friction and wear, down to the nanometer scale. Readers of this book will become familiar with the concepts and techniques of nanotribology, explained by an international team of scientists and engineers, actively involved and with long experience in this field. Edited by two pioneers in the field, 'Fundamentals of Frictions and Wear at the Nanoscale' is suitable both as first introduction to this fascinating subject, and also as a reference for researchers wishing to improve their knowledge of nanotribology and to keep up with the latest results in this field.
Energy-efficient reprogramming of heterogeneous wireless sensor networks
(InTechOpen, 2010-12) Harte, Seán; Rollo, Stefano; Popovici, Emanuel M.; O'Flynn, Brendan; Seah, Winston; Kheng Tan, Yen; Science Foundation Ireland
Addressing non-linear hardware limitations and extending network coverage area for power aware wireless sensor networks
(InTech, 2011-06) Walsh, Michael; Hayes, Martin J.; Tarannum, Suraiya; Science Foundation Ireland; Irish Research Council for Science Engineering and Technology
Organometallic-metallic-cyclotriphosphazene mixtures: solid state method for metallic nanoparticle growth
(Nova Science Publishers, 2013-04) Díaz, Carlos; Valenzuela, María Luisa; O'Dwyer, Colm; Roger Dong; Fondo Nacional de Desarrollo Científico, Tecnológico y de Innovación Tecnológica
We review a recent general solid state method to obtain metallic, metal oxide and phosphate nanoparticles and crystals by pyrolysis at 800°C using organometallic derivatives of cyclo and polyphosphazene precursors containing diverse organometallic fragments linked to polymeric or oligomeric phosphazenes. When the preparation of the molecular precursor is not possible or results in low yield, an alternative method using solid state mixtures of the type MLn/N3P3[O2C12H8]n, where MLn can be a single metallic salt, and a coordination compound or an organometallic, is possible. For AuCl(PPh3)/[NP(O2C12H8)]n mixtures, single crystal cubic Au nanoparticles form, whose morphology, crystal shape, size and distribution strongly depends on deposition quantity and the mixture molar ratio. Nanoparticles as small as 3.5 nm are observed if the mixture is prepared in a crucible and varied geometries of microcrystals found when the mixture was deposited on Si or SiO2 wafers, including single-crystal gold fullerene structures. Extension to Ag, Pd and Re-containing precursor mixtures such as Ag(PPh3)(CF3SO3)/ [NP(O2C12H8)]3, PdCl2/N3P3[O2C12H8]3, and KReO4/N3P3[O2C12H8]3 allows microcrystal formation during pyrolysis. A thermally induced phase demixing mechanism describes the evolution of the crystal growth, aided microphase separation of the polymer mixture. This microphase demixing is shown to be an overarching mechanism involved in the nano to micro scale growth of crystals. A probable mechanism of the atomic and molecular-level chemistry is also proposed based on decomposition of the macromolecular polymeric, trimer and oligomeric precursors for the initial stages.
Carbon nanotube composites for electronic interconnect applications
(InTech, 2013-05) Chowdhury, Tamjid; Rohan, James F.; Suzuki, Satoru; Irish Research Council for Science, Engineering and Technology
Frontiers of Cu electrodeposition and electroless plating for on-chip interconnects
(Springer, 2013-11-21) Rohan, James F.; Thompson, Damien; Kondo, Kazuo; Akolkar, Rohan N.; Barkey, Dale P.; Yokoi, Masayuki; Enterprise Ireland; IDA Ireland; Science Foundation Ireland; Collaborative Centre for Applied Nanotechnology
In the electronics industry, interconnect is defined as a conductive connection between two or more circuit elements. It interconnects elements (transistor, resistors, etc.) on an integrated circuit or components on a printed circuit board. The main function of the interconnect is to contact the junctions and gates between device cells and input/output (I/O) signal pads. These functions require specific material properties. For performance or speed, the metallization structure should have low resistance and capacitance. For reliability, it is important to have the capability of carrying high current density, stability against thermal annealing, resistance against corrosion and good mechanical properties.
FIB patterning of stainless steel for the development of nano-structured stent surfaces for cardiovascular applications
(Springer International Publishing, 2013-12-06) Schmidt, Michael; Nazneen, F.; Galvin, Paul; Petkov, Nikolay; Holmes, Justin D.; Wang, M. Z.; Higher Education Authority; Science Foundation Ireland; National Biophotonics and Imaging Platform Ireland
Stent implantation is a percutaneous interventional procedure that mitigates vessel stenosis, providing mechanical support within the artery and as such a very valuable tool in the fight against coronary artery disease. However, stenting causes physical damage to the arterial wall. It is well accepted that a valuable route to reduce in-stent re-stenosis can be based on promoting cell response to nano-structured stainless steel (SS) surfaces such as by patterning nano-pits in SS. In this regard patterning by focused ion beam (FIB) milling offers several advantages for flexible prototyping. On the other hand FIB patterning of polycrystalline metals is greatly influenced by channelling effects and redeposition. Correlative microscopy methods present an opportunity to study such effects comprehensively and derive structure–property understanding that is important for developing improved patterning. In this chapter we present a FIB patterning protocol for nano-structuring features (concaves) ordered in rectangular arrays on pre-polished 316L stainless steel surfaces. An investigation based on correlative microscopy approach of the size, shape and depth of the developed arrays in relation to the crystal orientation of the underlying SS domains is presented. The correlative microscopy protocol is based on cross-correlation of top-view scanning electron microscopy, electron backscattering diffraction, atomic force microscopy and cross-sectional (serial) sectioning. Various FIB tests were performed, aiming at improved productivity by preserving nano-size accuracy of the patterned process. The optimal FIB patterning conditions for achieving reasonably high throughput (patterned rate of about 0.03 mm2/h) and nano-size accuracy in dimensions and shapes of the features are discussed as well.
Energy storage: battery materials and architectures at the nanoscale
(Intech, 2014-02) Rohan, James F.; Hasan, Maksudul; Patil, Sanjay; Casey, Declan P.; Clancy, Tomás M.; Enterprise Ireland; European Commission
Smart energy management and conversion
(Wiley, 2014-05-04) Wang, Wensi; Rohan, James F.; Wang, Ningning; Hayes, Mike; Romani, Aldo; Macrelli, Enrico; Dini, Michele; Filippi, Matteo; Tartagni, Marco; Flandre, Denis
This chapter introduced power management circuits and energy storage unit designs for sub‐1 mW low power energy harvesting technologies, including indoor light energy harvesting, thermoelectric energy harvesting and vibration energy harvesting. The solutions address several of the problems associated with energy harvesting, power management and storage issues including low voltage operation, self‐start, efficiency (conversion efficiency as well as impact of power consumption of the power management circuit itself), energy density and leakage current levels. Additionally, efforts to miniaturize and integrate magnetic parts as well as integrate discrete circuits onto silicon are outlined to offer improvements in cost, size and efficiency. Finally initial results from efforts to improve energy density of storage devices using nanomaterials are introduced.
Molecular layer doping: non-destructive doping of silicon and germanium
(IEEE, 2014-06) Long, Brenda; Verni, Giuseppe A.; O'Connell, John; Holmes, Justin D.; Shayesteh, Maryam; O'Connell, Dan; Duffy, Ray
This work describes a non-destructive method to introduce impurity atoms into silicon (Si) and germanium (Ge) using Molecular Layer Doping (MLD). Molecules containing dopant atoms (arsenic) were designed, synthesized and chemically bound in self-limiting monolayers to the semiconductor surface. Subsequent annealing enabled diffusion of the dopant atom into the substrate. Material characterization included assessment of surface analysis (AFM) and impurity and carrier concentrations (ECV). Record carrier concentration levels of arsenic (As) in Si (~5Ã 10^20 atoms/cm3) by diffusion doping have been achieved, and to the best of our knowledge this work is the first demonstration of doping Ge by MLD. Furthermore due to the ever increasing surface to bulk ratio of future devices (FinFets, MugFETs, nanowire-FETS) surface packing spacing requirements of MLD dopant molecules is becoming more relaxed. It is estimated that a molecular spacing of 2 nm and 3 nm is required to achieve doping concentration of 10^20 atoms/cm3 in a 5 nm wide fin and 5 nm diameter nanowire respectively. From a molecular perspective this is readily achievable.
Gold nanoparticles: synthesis, characterization, and bioconjugation
(CRC Press, Taylor & Francis, 2015-09) Rahme, Kamil; Holmes, Justin D.; Lyshevski, Sergey E.
Gold nanoparticles (Au NPs) with diameters ranging between 4-150 nm have been synthesized in water. The strong reducing agent sodium borohydride (NaBH4) was used to produce small Au NPs with diameter about 4 +_1 nm. 15 and 30 nm Au NPs were obtained by a slightly modified Turkevich and Frens method using sodium citrate as both reducing and stabilizing agent at high temperature. The attempt to produce Au NPs with diameter larger than 30-40 nm by the Turkevich method resulted in an increase in the polydispersity and the shape diversity of the final Au NPs, indicating the importance of the trial of new reducing agents in the production of Au NPs especially for diameters above 40 nm. Therefore, hydroxylamine-o-sulfonic acid (NH2SO4H) (HOS) was used here for the first time as a new reducing agent for HAuCl4 at room temperature to produce Au NPs with diameter of about 60, 90 and 150 nm. This new method using HOS is an extension of the approaches described to produce Au NPs with diameter above 40 nm by direct reduction. The obtained nanoparticles were characterized using uv-visible spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy (TEM). Further biocojuguation on 15, 30 and 90 nm Au NPs were performed by grafting covalently Apolipoprotein E (ApoE) and Bovine Serum Albumin (BSA) through an ethylene glycol-N-hydroxysuccinimide linker (NHS-PEG-S-S-PEG-NHS) making them very attractive for drug delivery and cell targeting. Finally, functionalized polyethylene glycol-based thiol polymers were also used to stabilize the pre-synthesized Au NPs-PEG-Protein.
Novel approaches for genuine single phase room temperature magnetoelectric multiferroics
(Wiley, 2016-05) Keeney, Lynette; Schmidt, Michael; Amann, Andreas; Maity, Tuhin; Deepak, Nitin; Faraz, Ahmad; Petkov, Nikolay; Roy, Saibal; Pemble, Martyn E.; Whatmore, Roger W.; Alguero, Miguel; Gregg, J. Marty; Mitoseriu, Liliana; Science Foundation Ireland
This chapter reviews approaches currently under investigation for the fabrication of single‐phase magnetoelectric multiferroics, from bulk ceramics to those in thin‐film form. It presents an approach of inserting magnetic ions into the Aurivillius phase, layer‐structured ferroelectric materials, whereby thin films of average composition Bi6Ti2.8Fe1.52Mn0.68O18 (B6TFMO) demonstrate room temperature ferroelectricity, ferromagnetism, and magnetoelectric coupling. The chapter also discusses the importance of careful microstructural analysis of the materials and the application of a statistical model to determine a confidence level that the observed effects are from genuine single‐phase magnetoelectric multiferroics. It reviews how careful phase analysis and statistical treatment of the data confirmed that the B6TFMO phase is a single‐phase multiferroic to a confidence level of 99.5%. Finally, it summarizes how direct evidence of magnetoelectric coupling in the B6TFMO thin films was obtained. This review demonstrates that with materials development and design, the development of room temperature multiferroic materials can be achieved.
Energy challenges for ICT
(InTechOpen, 2017-03-22) Fagas, Giorgos; Gallagher, John P.; Gammaitoni, Luca; Paul, Douglas J.; Seventh Framework Programme
The energy consumption from the expanding use of information and communications technology (ICT) is unsustainable with present drivers, and it will impact heavily on the future climate change. However, ICT devices have the potential to contribute significantly to the reduction of CO2 emission and enhance resource efficiency in other sectors, e.g., transportation (through intelligent transportation and advanced driver assistance systems and self-driving vehicles), heating (through smart building control), and manufacturing (through digital automation based on smart autonomous sensors). To address the energy sustainability of ICT and capture the full potential of ICT in resource efficiency, a multidisciplinary ICT-energy community needs to be brought together covering devices, microarchitectures, ultra large-scale integration (ULSI), high-performance computing (HPC), energy harvesting, energy storage, system design, embedded systems, efficient electronics, static analysis, and computation. In this chapter, we introduce challenges and opportunities in this emerging field and a common framework to strive towards energy-sustainable ICT.
Nanohaiku and nanohaiga: nanotechnologies meet art
(изток-запад [East-West], 2017-11) Georgiev, Yordan M.; Panova, Nedyalka; Gangnaik, Anushka S.; Ghoshal, Tandra; Nikolova, Antoaneta; Holmes, Justin D.
The present work combines science and arts in an innovative and intriguing way. Using Electron Beam Lithography (EBL) and Directed Self-Assembly (DSA) of Block Co-Polymers (BCP) in conjunction with the shortest poetic form, haiku, the paper attractively demonstrate the capabilities of these nanofabrication techniques and explores the interaction between the top-down EBL process and the bottom-up DSA approach. Silicon (Si) substrates and EBL with the hydrogen silsesquioxane (HSQ) negative tone resist were used for capturing examples of the tiniest haiku poems written and translated into six languages having four different character styles. Subsequently, the haiku nanostructures (“nanohaiku”) were used as guiding features between which the poly(styrene)-blockpoly(ethylene oxide) (PS-b-PEO) diblock copolymer is spin coated to create self-organised nanopatterns. The annealing was done in toluene solvent vapours at 50°C for 1.5 hours and then the samples were immersed in ethanol for 15 hours at 40°C to dissolve the PEO copolymer. In areas within and in-between the individual characters and syllables of the poems, unusual patterns were observed. We interpret them as self-assembled “nanohaiga” directed by the morphology and the linguistic geometry of the nanohaiku. Moreover, we demonstrate how the BCP pattern changes when interacting with the same verse translated into different languages. Thus we add to the haiku poem's own nanostructure and meaning a new visual identity, nanohaiga, combining for the first time poetry, visual art and advanced nanofabrication technologies.
Bioconjugated gold nanoparticles enhance siRNA delivery in prostate cancer cells
(Springer, 2019-05-17) Rahme, Kamil; Guo, Jianfeng; Holmes, Justin D.; Dinesh Kumar, Lekha; Science Foundation Ireland; Irish Research Council; Department of Science and Technology of Jilin Province; National Council for Scientific Research
Here we describe a simple way to create a gold nanoparticle (AuNP)-based non-viral delivery system to deliver siRNA into prostate cancer cells. Therefore, positively charged polyethylenimine (PEI)-capped AuNPs were synthesized in water and further conjugated with the targeting ligand (folic acid) for folate receptors (AuNPs-PEI-FA). The AuNPs-PEI-FA could effectively complex small interfering RNA (siRNA) through electrostatic interaction. Flow cytometry displayed that AuNPs-PEI-FA could specifically deliver siRNA into LNCaP cells, a prostate cancer cell line overexpressing prostate-specific membrane antigen (PSMA) that exhibits a hydrolase enzymatic activity with a folate substrate. In contrast, internalization of siRNA into PC-3 cells, a prostate cancer cell line not expressing PSMA or folate receptors, was not achieved using AuNPs-PEI-FA.siRNA. Following endolysosomal escape, the AuNPs-PEI-FA-.siRNA formulation resulted in significant endogenous gene silencing when compared to the nontargeted formulation, suggesting the potential of AuNPs-PEI-FA for targeted delivery of therapeutic siRNAs in the treatment of prostate cancer.
Wearable technology supported home rehabilitation services in rural areas: emphasis on monitoring structures and activities of functional capacity. Handbook
(Publications of Karelia University of Applied Sciences B, 2019-10) Alamäki, Antti; Nevala, Elina; Barton, John; Condell, Joan; Munoz Esquivel. Karla; Nordström, Anna; Tedesco, Salvatore; Kelly, Daniel; Heaney. David; Tyndall National Institute, Cork Ireland; Ulster University; University College Cork; Västerbotten Läns Landsting; Umeå Universitet; Karelia University of Applied Sciences, Finland; European Regional Development Fund
The sustainability of modern healthcare systems is under threat. – the ageing of the population, the prevalence of chronic disease and a need to focus on wellness and preventative health management, in parallel with the treatment of disease, pose significant social and economic challenges. The current economic situation has made these issues more acute. Across Europe, healthcare expenditure is expected to rice to almost 16% of GDP by 2020. (OECD Health Statistics 2018). Coupled with a shortage of qualified personnel, European nations are facing increasing challenges in their ability to provide better-integrated and sustainable health and social services. The focus is currently shifting from treatment in a care center to prevention and health promotion outside the care institute. Improvements in technology offers one solution to innovate health care and meet demand at a low cost. New technology has the potential to decrease the need for hospitals and health stations (Lankila et al., 2016. In the future the use of new technologies – including health technologies, sensor technologies, digital media, mobile technology etc. - and digital services will dramatically increase interaction between healthcare personnel and customers (Deloitte Center for Health Solutions, 2015a; Deloitte Center for Health Solutions 2015b). Introduction of technology is expected to drive a change in healthcare delivery models and the relationship between patients and healthcare providers. Applications of wearable sensors are the most promising technology to aid health and social care providers deliver safe, more efficient and cost-effective care as well as improving people’s ability to self-manage their health and wellbeing, alert healthcare professionals to changes in their condition and support adherence to prescribed interventions. (Tedesco et al., 2017; Majumder et al., 2017). While it is true that wearable technology can change how healthcare is monitored and delivered, it is necessary to consider a few things when working towards the successful implementation of this new shift in health care. It raises challenges for the healthcare systems in how to implement these new technologies, and how the growing amount of information in clinical practice, integrates into the clinical workflows of healthcare providers. Future challenges for healthcare include how to use the developing technology in a way that will bring added value to healthcare professionals, healthcare organizations and patients without increasing the workload and cost of the healthcare services. For wearable technology developers, the challenge will be to develop solutions that can be easily integrated and used by healthcare professionals considering the existing constraints. This handbook summarizes key findings from clinical and laboratory-controlled demonstrator trials regarding wearables to assist rehabilitation professionals, who are planning the use of wearable sensors in rehabilitation processes. The handbook can also be used by those developing wearable sensor systems for clinical work and especially for use in hometype environments with specific emphasis on elderly patients, who are our major health care consumers.
An assessment of sputtered nitrogen-doped nickel oxide for all-oxide transparent optoelectronic applications: The case of hybrid NiO:N/TiO2 heterostructure
(B P International, 2022-02-12) Aivalioti, Chrysa; Papadakis, Alexandros; Manidakis, Emmanouil; Kayambaki, Maria; Androulidaki, Maria; Tsagaraki, Katerina; Pelekanos, Nikolaos T.; Stoumpos, Constantinos; Modreanu, Mircea; Crăciun, Gabriel; Romanitan, Cosmin; Aperathitis, Elias
ransition metal oxides present a unique category of materials due to their versatile optical, electrical and mechanical properties. Nickel oxide (NiO) is an intrinsic p-type oxide semiconductor. P-NiO with controllable and reproducible physico-chemical properties, if combined with transparency and low temperature (low-T) fabrication processes, can be fully exploited in many transparent and/or flexible devices for applications, like energy management (production, manipulation, storage), sensing, wearable and health care electronics, etc. Reproducibility, transparency and low-T fabrication processes of p-type NiO are the motivation of this work. Nitrogen is one of the dopants used for modifying the properties of NiO. Until now, nitrogen-doped NiO, has shown inferior properties than those of pure NiO. In this work, we present nitrogen-doped NiO (NiO:N) thin films with enhanced properties compared to those of the undoped NiO. The NiO:N films were grown by sputtering on room-temperature substrates in plasma containing 50% Ar and 50% (O2+N2) gases. The undoped NiO film was oxygen-rich, single-phase cubic NiO, having transmittance less than 20%. Upon doping with nitrogen, the films became more transparent (around 65%), had a wide direct band gap (up to 3.67 eV) and showed clear evidence of indirect band gap, 2.50-2.72 eV, depending on %(O2-N2) in plasma. The changes in the properties of the films such as structural disorder, energy band gap, Urbach states and resistivity were correlated with the incorporation of nitrogen in their structure. The optimum NiO:N film was used to form a diode with spin-coated, mesoporous on top of a compact, TiO2 film. The hybrid NiO:N/TiO2 heterojunction was transparent showing good output characteristics, as deduced using both I-V and Cheung’s methods. The diode’s transparency and characteristics were further enhanced upon thermal treatment and this was attributed to improved NiO:N properties with annealing. Transparent NiO:N films can be realized for all-oxide flexible optoelectronic devices.

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