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Aerosol assisted chemical vapour deposition (AACVD) has been used to deposit thin films of ZnO from the single-source precursor [Zn(OC(Me)CHC(Me)N( i Pr)) 2 ] ( 1 ) affording highly transparent (>80%) and conductive films (sheet resistance ∼70 KΩ/sq). Extension of this AACVD method whereby related precursors of the type, [R 2 M(OC(Me)CHC(Me)N( i Pr))] (R = Et, M = Al ( 2 ); R = Me, M = Ga ( 3 )), isolated as oils, were added to the precursor solution allowed for the deposition of aluminium- and gallium-doped ZnO (AZO and GZO) films, respectively. Complexes 1 – 3 were characterised by elemental analysis, NMR and mass spectrometry. Films were deposited in under 30 min at 400 °C, from CH 2 Cl 2 /toluene solutions with a N 2 carrier gas. Herein we report the bulk resistivity, ρ , of AZO (0.252 Ω cm) and GZO (0.756 Ω cm) films deposited from this novel approach. All the films transparency exceeded 80% in the visible, X-ray diffraction (XRD) showed all films to crystallise in the wurtzite phase whilst X-ray photoemission spectroscopy (XPS) confirmed the presence of the Al and Ga dopants in the films, and highlighted the low C-contamination (<5%) this route offers. Investigation of a mechanism analogous to the Kirkendall effect confirmed that heating of GZO films at 1000 °C produced the spinel structure GaZn 2 O 4 . [ABSTRACT FROM AUTHOR]

The use of zinc triflate (trifluoromethanesulfonate), [Zn(OTf) 2 ] as a precursor in the aerosol assisted chemical vapour deposition of zinc oxide thin films is described. Aluminum doped zinc oxide (AZO) thin films are also shown to be deposited when aluminum acetylacetonate [Al(acac) 3 ] was introduced into the precursor solution, illustrating the versatility of this system. Film characterization techniques include glancing angle X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and optical and electrical measurements. AZO films with an Al content of 7 at.% were found to have favourable transparent conducting oxide properties with simultaneous high transparency (> 80%) in the visible light region and a low electrical resistivity (1.96 × 10 − 3 Ω cm). [ABSTRACT FROM AUTHOR]

A conventional solution-based route to a cyclic trimeric organozinc compound [{Zn(Et)( β-diketonate)}3] ( β-diketonate=OC(OMe)CHC(Me)O, 1) is described, with 1 structurally characterized for the first time. The ligand selection of bidentate β-diketonates is shown to be key to isolating a cyclic trimer. Additional reaction of β-diketonates with diethyl zinc were spectroscopically characterized as compounds of the type [{Zn(Et)( β-diketonate)} n] ( β-diketonate=OC(Me)CHC(Me)O, 2, OC(O tBu)CHC(Me)O, 3). Further studies have shown that selective oxidation of these species produces cubanes of the general formula [{Zn(OC(R)CHC(Me)O)2Zn(Et)OEt}2] (R=OMe, 4; Me, 5; O tBu, 6), allowing a high oxygen content whilst remaining structurally suitable for use as precursors. The successful deposition of thin films of zinc oxide through aerosol-assisted chemical vapor deposition (AACVD), using a novel precursor, is described and fully characterized. [ABSTRACT FROM AUTHOR]

The β-ketoimine ligand [(Me)CN(H){iPr}–CHC(Me)=O] (L1H) and the bis(β-ketoimine) ligands [(CH2)2{N(H)C(Me)–CHC(R)=O}2] (L2H2, R = Me; L3H2, R = C6H5) linked by ethylene bridges have been used to form aluminium and gallium complexes: [Al(L1)Et2] (1), [Ga(L1)2Cl] (2), [AlL2(OiPr)] (3) and [GaL3Me] (4). The complexes were characterised by NMR spectroscopy, mass spectroscopy, and single crystal X-ray diffraction, with the exception of 1 which was isolated as an oil. Compounds 1–4 have been used for the first time as single source precursors for the deposition of Al2O3 (1, 3) and Ga2O3 (2, 4) respectively. Thin films were deposited via aerosol assisted (AA)CVD with toluene as the solvent. [ABSTRACT FROM AUTHOR]

Vanadium(V) oxytrichloride was reacted with 2,4-pentanedione, diethyl malonate, and diethyl succinate under inert conditions, forming compounds: dichloro(oxo)(2,4-pentanedione) vanadium(V) [ 1 ], dichloro(oxo)(diethyl malonate) vanadium(IV) [ 2 ] and dichloro(oxo)(diethyl succinate) vanadium(IV) [ 3 ]. Compounds 1 – 3 are coordinated to the vanadium centre through the two carbonyl oxygen atoms of the bidentate ligand. It was determined by X-ray crystallography that the structures of the resulting complexes were significantly different, resulting in a monomeric complex ( 1 ), a tetrameric ring ( 2 ) and a 1D coordination polymer ( 3 ). Following the synthesis and isolation of 1 – 3 , they were tested as precursors for vanadium nitride and vanadium carbide by annealing under nitrogen and argon respectively at 1200 °C for 24 h. The resulting materials were characterised by: XRD, EDS, XPS and TEM. [ABSTRACT FROM AUTHOR]