Sophie L. Benjamin

Bio: Sophie L. Benjamin is an academic researcher from Nottingham Trent University. The author has contributed to research in topics: Thin film & Chemical vapor deposition. The author has an hindex of 14, co-authored 39 publications receiving 589 citations. Previous affiliations of Sophie L. Benjamin include University of Southampton.

Medium and high oxidation state metal/non-metal fluoride and oxide–fluoride complexes with neutral donor ligands

Abstract: While most high and medium oxidation state (O.S. ≥ 3) metal and non-metal fluorides and oxide fluorides are strong Lewis acids, exploration of their coordination chemistry with neutral ligands has been limited and mostly non-systematic. This is despite the very different properties conferred on the acceptor centre by the small electronegative fluoride ligands compared to the heavier halides. This article sets out these key differences, discusses possible synthetic routes, the key characterisation techniques, and appropriate bonding models. Current knowledge of the coordination chemistry of d, f and p-block fluorides and oxide fluorides with neutral ligands (with donor atoms drawn from Groups 15 and 16 and including N-heterocyclic carbenes) is then presented and discussed, and the differences in properties compared to complexes containing the heavier halides are illustrated. The emphasis is on work published post 1990, but earlier work is also included as essential background and where no more recent information exists. Attention is drawn to unexplored areas meriting investigation and to possible applications of these complexes.

Chemical vapour deposition of antimony chalcogenides with positional and orientational control: precursor design and substrate selectivity

Abstract: A series of alkylchalcogenostibines, Me2SbSenBu, MeSb(SenBu)2, Sb(SenBu)3 and MeSb(TenBu)2, have been designed and synthesised as potential precursors for chemical vapour deposition (CVD) by reaction of nBuELi (E = Se, Te) with the appropriate halostibine, Me3−nSbCln (n = 1, 2, 3), and characterised by 1H, 13C{1H} and 77Se{1H} or 125Te{1H} NMR spectroscopy as appropriate. MeSb(SenBu)2 and MeSb(TenBu)2 are very effective single source precursors for the low pressure CVD of high quality crystalline thin films of Sb2Se3 and Sb2Te3, respectively, confirmed by scanning electron microscopy, energy dispersive X-ray spectroscopy, Raman spectroscopy and thin film X-ray diffraction. Hall conductivity, carrier mobility, carrier density and, in the case of Sb2Te3, Seebeck coefficient measurements reveal electronic characteristics comparable with Sb2E3 deposited by atomic layer deposition or molecular beam epitaxy, suggesting materials quality and performance suitable for incorporation into electronic device structures. Choice of substrate and deposition conditions were found to significantly affect the morphology and preferred orientation of Sb2Te3 crystallites, enabling deposition of films with either 〈1 1 0〉 or 〈0 0 1〉 alignment. Use of micro-patterned substrates allowed selective deposition of crystalline 2D micro-arrays of Sb2Te3 onto exposed TiN surfaces only.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Damascene copper electroplating for chip interconnections

Abstract: Damascene copper electroplating for on-chip interconnections, a process that we conceived and developed in the early 1990s, makes it possible to fill submicron trenches and vias with copper without creating a void or a seam and has thus proven superior to other technologies of copper deposition. We discuss here the relationship of additives in the plating bath to superfilling, the phenomenon that results in superconformal coverage, and we present a numerical model which accounts for the experimentally observed profile evolution of the plated metal.

Two-dimensional transistors beyond graphene and TMDCs

Abstract: Two-dimensional semiconductors (2DSCs) have attracted considerable attention as atomically thin channel materials for field-effect transistors. Each layer in 2DSCs consists of a single- or few-atom-thick, covalently bonded lattice, in which all carriers are confined in their atomically thin channel with superior gate controllability and greatly suppressed OFF-state current, in contrast to typical bulk semiconductors plagued by short channel effects and heat generation from static power. Additionally, 2DSCs are free of surface dangling bonds that plague traditional semiconductors, and hence exhibit excellent electronic properties at the limit of single atom thickness. Therefore, 2DSCs can offer significant potential for the ultimate transistor scaling to single atomic body thickness. Earlier studies of graphene transistors have been limited by the zero bandgap and low ON–OFF ratio of graphene, and transition metal dichalcogenide (TMDC) devices are typically plagued by insufficient carrier mobility. To this end, considerable efforts have been devoted towards searching for new 2DSCs with optimum electronic properties. Within a relatively short period of time, a large number of 2DSCs have been demonstrated to exhibit unprecedented characteristics or unique functionalities. Here we review the recent efforts and progress in exploring novel 2DSCs beyond graphene and TMDCs for ultra-thin body transistors, discussing the merits, limits and prospects of each material.

Characterization of basic physical properties of Sb 2 Se 3 and its relevance for photovoltaics

Abstract: Antimony selenide (Sb2Se3) is a promising absorber material for thin film photovoltaics because of its attractive material, optical and electrical properties. In recent years, the power conversion efficiency (PCE) of Sb2Se3 thin film solar cells has gradually enhanced to 5.6%. In this article, we systematically studied the basic physical properties of Sb2Se3 such as dielectric constant, anisotropic mobility, carrier lifetime, diffusion length, defect depth, defect density and optical band tail states.We believe such a comprehensive characterization of the basic physical properties of Sb2Se3 lays a solid foundation for further optimization of solar device performance.