The distorted octahedral complexes [SnCl4{ n BuSe­(CH2) n Se n Bu}] (n = 2 or 3), (1) and (2), obtained from reaction of SnCl4 with the neutral bidentate ligands and characterized by IR/Raman and multinuclear (1H, 77Se­{1H} and 119Sn) NMR spectroscopy and X-ray crystallography, serve as very effective single source precursors for low pressure chemical vapor deposition (LPCVD) of microcrystalline, single phase tin diselenide films onto SiO2, Si and TiN substrates. Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) imaging show hexagonal plate crystallites which grow perpendicular to the substrate surface in the thicker films, but align mostly parallel to the surface when the quantity of reagent is reduced to limit the film thickness. X-ray diffraction (XRD) and Raman spectroscopy on the deposited films are consistent with hexagonal SnSe2 (P3̅m1; a = b = 3.81 Å; c = 6.13 Å), with strong evidence for preferred orientation of the crystallites in thinner (0.5–2 μm) samples, consistent with crystal plate growth parallel to the substrate surface. Hall measurements show the deposited SnSe2 is a n-type semiconductor. The resistivity of the crystalline films is 210 (±10) mΩ cm and carrier density is 5.0 × 1018 cm–3. Very highly selective film growth from these reagents onto photolithographically patterned substrates is observed, with deposition strongly preferred onto the (conducting) TiN surfaces of SiO2/TiN patterned substrates, and onto the SiO2 surfaces of Si/SiO2 patterned substrates. A correlation between the high selectivity and high contact angle of a water droplet on the substrate surfaces is observed.

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A series of alkylchalcogenostibines have been synthesised and employed as precursors for the chemical vapour deposition of Sb2Te3 and Sb2Se3. Variations in substrate and temperature give different film morphologies, and patterned arrays can be deposited using substrate selectivity.

Poly(N-isopropylacrylamide) (PNIPAm) is widely used to fabricate cell sheet surfaces for cell culturing, however copolymer and interpenetrated polymer networks based on PNIPAm have been rarely explored in the context of tissue engineering. Many complex and expensive techniques have been employed to produce PNIPAm-based films for cell culturing. Among them, spin coating has demonstrated to be a rapid fabrication process of thin layers with high reproducibility and uniformity. In this study, we introduce an innovative approach to produce anchored smart thin films both thermo- and electro-responsive, with the aim to integrate them in electronic devices and better control or mimic different environments for cells in vitro. Thin films were obtained by spin coating of colloidal solutions made by PNIPAm and PAAc nanogels. Anchoring the films to the substrates was obtained through heat treatment in the presence of dithiol molecules. From analyses carried out with AFM and XPS, the final samples exhibited a flat morphology and high stability to water washing. Viability tests with cells were finally carried out to demonstrate that this approach may represent a promising route to integrate those hydrogels films in electronic platforms for cell culture applications.

We report a new method for electrodeposition of device-quality metal chalcogenide semiconductor thin films and nanostructures from a single, highly tuneable, non-aqueous electrolyte. This method opens up the prospect of electrochemical preparation of a wide range of functional semiconducting metal chalcogenide alloys that have applications in various nano-technology areas, ranging from the electronics industry to thermoelectric devices and photovoltaic materials. The functional operation of the new method is demonstrated by means of its application to deposit the technologically important ternary Ge/Sb/Te alloy, GST-225, for fabrication of nanostructured phase change memory (PCM) devices and the quality of the material is confirmed by phase cycling via electrical pulsed switching of both the nano-cells and thin films.

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† Electronic supplementary information (ESI) available: Details of substrate preparation and characterisation of the Bi 2 Te 3 thin lms; thermogravimetric analysis (TGA) of [BiCl 3 (Te n Bu 2) 3 ], SEM images of thin lms of Bi 2 Te 3 , Raman analysis of Bi 2 Te 3 thin lms, WDX compositional analysis of Bi 2 Te 3 thin lms, and microfocus and pole gure XRD analysis of micro-scale Bi 2 Te 3 arrays, lattice parameters rened for Bi 2 Te 3 grown on different substrates. See

The neutral complexes [GaCl 3 (E n Bu 2 )] (E = Se or Te), [(GaCl 3 ) 2 { n BuE(CH 2 ) n E n Bu}] (E = Se, n = 2; E = Te, n = 3), and [(GaCl 3 ) 2 { t BuTe(CH 2 ) 3 Te t Bu}] are conveniently prepared by reaction of GaCl 3 with the neutral E n Bu 2 in a 1:1 ratio or with n BuE(CH 2 ) n E n Bu or t BuTe(CH 2 ) 3 Te t Bu in a 2:1 ratio and characterized by IR/Raman and multinuclear ( 1 H, 71 Ga, 77 Se-{ 1 H}, and 125 Te{ 1 H}) NMR spectroscopy, respectively, all of which indicate distorted tetrahedral coordination at Ga. The tribromide analog, [GaBr 3 (Se n Bu 2 )], was prepared and characterized similarly. A crystal structure determination on [(GaCl 3 ) 2 { t BuTe(CH 2 ) 3 Te t Bu}] confirms this geometry with each pyramidal GaCl 3 fragment coordinated to one Te donor atom of the bridging ditelluroether, Ga−Te = 2.6356(13) and 2.6378(14) Å. The n Bu-substituted ligand complexes serve as convenient and very useful single source precursors for low pressure chemical vapor deposition (LPCVD) of single phase gallium telluride and gallium selenide, Ga 2 E 3 , films onto SiO 2 and TiN substrates. The composition and morphology were confirmed by SEM, EDX, and Raman spectroscopy, while XRD shows the films are crystalline, consistent with cubic Ga 2 Te 3 (F4̅ 3m) and monoclinic Ga 2 Se 3 (Cc), respectively. Hall measurements on films grown on SiO 2 show the Ga 2 Te 3 is a p-type semiconductor with a resistivity of 195 ± 10 Ω cm and a carrier density of 5 × 10 15 cm −3 , indicative of a close to stoichiometric compound. The Ga 2 Se 3 is also p-type with a resistivity of (9 ± 1) × 10 3 Ω cm, a carrier density of 2 × 10 13 cm −3 , and a mobility of 20−80 cm 2 / V·s. Competitive deposition of Ga 2 Te 3 onto a photolithographically patterned SiO 2 /TiN substrate indicates that film growth onto the conducting and more hydrophobic TiN is preferred.