12 research outputs found
Solution processed SnO2:Sb transparent conductive oxide as an alternative to indium tin oxide for applications in organic light emitting diodes
Here we present the deposition of antimony-doped tin oxide thin films using the ambient spray pyrolysis technique and demonstrate their implementation as transparent electrodes (anodes) in red, green and blue Organic Light emitting diodes. The films were spray coated at 380 oC from SnCl4 and SbCl3 solution blends in methanol and ∼230 nm thick films were investigated by means of x-ray diffraction, AFM, UV-Vis absorption spectroscopy, 4-point probe, Hall Effect and Kelvin Probe. It was found that for optimum antimony doping in the precursor solution of ∼2 wt%, the as-deposited ATO films exhibit excellent characteristics such as low surface roughness of RRMS∼6.3 nm, high work function (∼ -5.03 eV), wide direct band gap (∼4.2 eV), high transparency in the visible spectrum in excess of 85 % on glass, low sheet resistivity (∼32 Ohms/sq), high charge carrier concentration (∼6.35 × 10^20 cm-3) and carrier mobility of ∼32 cm2 V-1 s-1. Furthermore, the electrical and optical performance i.e. the turn on voltage and external quantum efficiency of red, green and blue OLEDs fabricated on optimized SnO2:Sb films were identical to those of OLEDs fabricated on commercially available ITO (Rs∼15 Ohms/sq) and were found to be in excess of 11 %, 0.3 % and 13 % for red, green and blue OLEDs respectivel
The contribution of musculoskeletal disorders in multimorbidity: Implications for practice and policy
People frequently live for many years with multiple chronic conditions (multimorbidity) that impair health outcomes and are expensive to manage. Multimorbidity has been shown to reduce quality of life and increase mortality. People with multimorbidity also rely more heavily on health and care services and have poorer work outcomes. Musculoskeletal disorders (MSDs) are ubiquitous in multimorbidity because of their high prevalence, shared risk factors, and shared pathogenic processes amongst other long-term conditions. Additionally, these conditions significantly contribute to the total impact of multimorbidity, having been shown to reduce quality of life, increase work disability, and increase treatment burden and healthcare costs. For people living with multimorbidity, MSDs could impair the ability to cope and maintain health and independence, leading to precipitous physical and social decline. Recognition, by health professionals, policymakers, non-profit organisations, and research funders, of the impact of musculoskeletal health in multimorbidity is essential when planning support for people living with multimorbidity
High-mobility ZnO thin film transistors based on solution-processed hafnium oxide gate dielectrics
The properties of metal oxides with high dielectric constant (k) are being extensively studied for use as gate dielectric alternatives to silicon dioxide (SiO2). Despite their attractive properties, these high-k dielectrics are usually manufactured using costly vacuum-based techniques. In that respect, recent research has been focused on the development of alternative deposition methods based on solution-processable metal oxides. Here, the application of the spray pyrolysis (SP) technique for processing high-quality hafnium oxide (HfO2) gate dielectrics and their implementation in thin film transistors employing spray-coated zinc oxide (ZnO) semiconducting channels are reported. The films are studied by means of admittance spectroscopy, atomic force microscopy, X-ray diffraction, UV-Visible absorption spectroscopy, FTIR, spectroscopic ellipsometry, and field-effect measurements. Analyses reveal polycrystalline HfO2 layers of monoclinic structure that exhibit wide band gap (≈5.7 eV), low roughness (≈0.8 nm), high dielectric constant (k ≈ 18.8), and high breakdown voltage (≈2.7 MV/cm). Thin film transistors based on HfO2/ZnO stacks exhibit excellent electron transport characteristics with low operating voltages (≈6 V), high on/off current modulation ratio (∼107) and electron mobility in excess of 40 cm2 V-1 s-1
Solution processed lanthanum aluminate gate dielectrics for use in metal oxide-based thin film transistors
We report on ZnO-based thin-film transistors (TFTs) employing lanthanum aluminate gate dielectrics (LaxAl1-xOy) grown by spray pyrolysis in ambient atmosphere at 440 °C. The structural, electronic, optical, morphological, and electrical properties of the LaxAl1-xOy films and devices as a function of the lanthanum to aluminium atomic ratio were investigated using a wide range of characterization techniques such as UV-visible absorption spectroscopy, impedance spectroscopy, spectroscopic ellipsometry, atomic force microscopy, x-ray diffraction, and field-effect measurements. As-deposited LaAlOy dielectrics exhibit a wide band gap (∼6.18 eV), high dielectric constant (k ∼ 16), low roughness (∼1.9 nm), and very low leakage currents (2). TFTs employing solution processed LaAlOy gate dielectrics and ZnO semiconducting channels exhibit excellent electron transport characteristics with hysteresis-free operation, low operation voltages (∼10 V), high on/off current modulation ratio of >106, subthreshold swing of ∼650 mV dec-1, and electron mobility of ∼12 cm2 V-1 s-1
A review of the risks associated with children and young people’s social media use and the implications for social work practice
This paper explores what the research says about the risks to children and young people of using social media. Taking a systematic approach this literature search identified 16 peer reviewed articles, written in English since January 2010. Four areas of risk were identified: cyberbullying and online abuse, exposure to negative forms of user-generated content, the converging of offline and online networks, and developing interpretations of privacy. The research also highlighted how the extent of the risk depends upon the developmental stage and social circumstances. This review provides several implications for social work practice. Social workers must develop their understanding of different social media platforms in order to identify risks and maximise opportunities. Assessment approaches must be tailored to ensure social media use and its effect on those of different ages and backgrounds is considered. Finally they need to consider their role in educating about the risks of social media use