Atomic layer deposition of TbF3 thin films

Lanthanide fluoride thin films have gained interest as materials for various optical applications, including electroluminescent displays and mid-IR lasers. However, the number of atomic layer deposition (ALD) processes for lanthanide fluorides has remained low. In this work, we present an ALD process for TbF3 using tris(2,2,6,6-tetramethyl-3,5-heptanedionato)terbium and TiF4 as precursors. The films were grown at 175-350 degrees C. The process yields weakly crystalline films at the lowest deposition temperature, whereas strongly crystalline, orthorhombic TbF3 films are obtained at higher temperatures. The films deposited at 275-350 degrees C are exceptionally pure, with low contents of C, O, and H, and the content of titanium is below the detection limit (Peer reviewe

Mapping the dependence of black carbon radiative forcing on emission region and season

Peer reviewe

Congruence between graduating nursing students' self-assessments and mentors' assessments of students' nurse competence

Self-assessment is widely used to assess competence in health care, although there is evidence of the weaknesses of self-assessment in the literature. In general, the process of self-assessment has been found to stimulate students' deep-level learning and problem-solving skills. Nursing students need to develop their self-assessment skills in order to identify their learning and ensure up-to-date outcomes and safe practice. This study aims to assess the congruence between graduating nursing students' self-assessment and their mentors' assessments concerning nurse competence with particular focus on nursing skills. The data were collected in November December 2011 in the last week of final clinical placement of nurse education. Completed questionnaires were received from 60 students and 50 mentors. From these, 42 student mentor pairs were matched for the sample of this study. Descriptive and inferential statistics were used in the data analysis. Comparisons between the assessments showed that students assessed their nurse competence as higher than their mentors (VAS 64.5 +/- 12.2 vs. 56.7 +/- 19.0). In nursing skills, the assessments were closer to each other (VAS 75.4 +/- 12.8 vs. 72.2 +/- 16.7); however, students' assessments still remained higher than those of mentors'. No congruent assessments were found between students and mentors. Compared to mentors' assessments, students overestimated their nurse competence. However, the results may be due to different understanding of nurse competence, and more research is needed on students' self-assessment by comparing students' assessments with those of peers, mentors and/or educators or knowledge tests. Nursing students should practise self-assessment during their nurse education. Mentors would also benefit practising in assessing students' nurse competence. (C) 2015 Australian College of Nursing Ltd. Published by Elsevier Ltd.Peer reviewe

Highly conductive and stable Co9S8 thin films by atomic layer deposition : from process development and film characterization to selective and epitaxial growth

Co9S8 is an interesting sulfide material with metallic conductivity that has shown promise for various energy applications. Herein, we report a new atomic layer deposition process producing crystalline, pure, and highly conductive Co9S8 thin films using CoCl2(TMEDA) (TMEDA = N,N,N ',N '-tetramethylethylenediamine) and H2S as precursors at 180-300 degrees C. The lowest resistivity of 80 mu omega cm, best uniformity, and highest growth rate are achieved at 275 degrees C. Area-selective deposition is enabled by inherent substrate-dependency of film nucleation. We show that a continuous and conductive Co9S8 film can be prepared on oxide-covered silicon without any growth on Si-H. Besides silicon, Co9S8 films can be grown on a variety of substrates. The first example of an epitaxial Co9S8 film is shown using a GaN substrate. The Co9S8 films are stable up to 750 degrees C in N-2, 400 degrees C in forming gas, and 225 degrees C in O-2 atmosphere. The reported ALD process offers a scalable and cost-effective route to high-quality Co9S8 films, which are of interest for applications ranging from electrocatalysis and rechargeable batteries to metal barrier and liner layers in microelectronics and beyond.Peer reviewe

Nickel Germanide Thin Films by Atomic Layer Deposition

This work presents preparation of nickel germanide (Ni2Ge) thin films by atomic layer deposition (ALD). The films were grown using NiCl2(tmpda) (tmpda = N,N,N',N',-tetramethyl-1,3-propanediamine) and tributylgermanium hydride serving as a new, efficient reducing agent. This is the first time ALD NixGey films are prepared directly upon the combination of two precursors and without any annealing treatment. NixGey is an important contact material for enabling Ge-based transistors and thus circumventing the scaling issues related to current microelectronics. The Ni2Ge process was examined at low temperatures of 160-200 degrees C. Self-limiting, saturative growth with a high growth rate of 0.91 angstrom/cycle was observed at 180 degrees C. The films were thoroughly analyzed in terms of morphology, crystallinity, composition, and resistivity. The Ni2Ge films were pure, with the sum of contaminants being less than 1 at. %. Owing to their high purity, the films exhibited low resistivity, suggesting suitability for contact applications.Peer reviewe

Mapping the dependence of black carbon radiative forcing on emission region and season

Peer reviewe

Disappearance of Biodiversity and Future of Our Foods

“I. Uluslararası Organik Tarım ve Biyoçeşitlilik Sempozyumu 27-29 Eylül Bayburt