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Al-doped ZnO films were grown on different orientation sapphire substrates (sapphire-R, C, M, A) at 400–600 °C via the atmospheric pressure aerosol-assisted MOCVD technique. The influence of deposition temperature and orientation of sapphire substrate on the microstructure, electrical and optical properties of ZnO-Al films was investigated. Epitaxial films grown on sapphire-R substrates exhibited the best electrical properties: carrier mobility was 50–60 cm2V−1s−1, resistivity <10−3Ω cm. The conditions of post-deposition treatment of films (gas atmosphere during film cooling after deposition, ex-situ annealing) had a marked influence on the electrical properties of films. [ABSTRACT FROM PUBLISHER]

Abstract: Films of chalcogenide Ge–Sb–Te materials were grown by pulsed liquid injection chemical vapor deposition (CVD) technique. Simple thermal CVD without additional process activation and CVD with remote activation of precursor decomposition process by a hot-wire were investigated and compared. Ge(NMe2)4, Sb(NMe2)3 and Te(i-Pr)2 precursors in a form of diluted solutions in toluene were used for depositions. Film composition was controlled by injection parameters, while the thickness was directly related with number of pulses. Hot-wire activated CVD process allows the growth of chalcogenide films of clearly better quality compared to films grown by standard thermal CVD. Uniform, smooth, crystalline Ge2Sb2Te5 films were grown at substrate/wire temperature 300°C/550°C and pressure⩽15Torr, using nitrogen as a carrier gas, on Si, Si/SiO2, Si/Si3N4 and glass substrates. Forty to forty five nanometer thick films on Si/SiO2 substrates showed reversible electrical and optical phase switching behavior. [Copyright &y& Elsevier]

In-, Ga- and Al-doped ZnO films were grown via the aerosol-assisted MOCVD technique using the following air-stable metal-organic precursors: Zn(thd) 2, In(thd) 3 , Al(thd) 3 and Ga(acac) 3 (thd = 2,2,6,6-tetramethyl-3,5-heptanedione, acac = acetylacetonate). Solution of a precursor mixture in 1,2-dimethoxyethane was transformed into an aerosol via ultrasound (2.56 MHz), and then the aerosol was transported into the deposition zone by N 2 + O 2 gas. The depositions were performed at 350–600 °C. The influences of the substrate, the deposition temperature, the doping element and the doping level on the structural, and the electrical and optical properties of the films were investigated using various characterisation techniques: XRD, SEM, AFM, UV–Vis and FT-IR spectroscopies, and Hall measurements. Epitaxial films on sapphire-R substrates exhibited the best electrical properties. Films doped by Ga and Al had lower resistivity compared to In-doped films. The best Ga- and Al-doped ZnO films (~ 150–200 nm thick) grown on sapphire-R at 400 °C exhibited a resistivity of ≈(7–8) × 10 − 4 Ω cm, a carrier concentration of ≈ 1.5 × 10 20 cm − 3 and a relatively high carrier mobility of ≈ 50–60 cm 2 V − 1 s − 1 . Because the low resistivity of Ga- and Al-doped films was mainly determined by the high carrier mobility, the optical transmittance (T) was high in both the visible (T > 90%) and the mid-IR spectral ranges (T ≈ 90% at λ = 2.5 μm). High transmittance in the mid-IR spectral range makes these films suitable for use as transparent electrodes in applications of the IR optoelectronic devices. Annealing of the films for 30 min at 400 °C in an Ar + H 2 (10%) mixture markedly increased the carrier concentration, which resulted in the increase in the optical band gap (up to ≈ 3.5 eV) and in the decrease in film resistivity and transparency in the mid-IR spectral range. Annealed Al- and Ga-doped films exhibited a resistivity of ≈(4 − 6) × 10 − 4 Ω cm. [ABSTRACT FROM AUTHOR]

Abstract: The influence of deposition conditions (pressure, growth rate, solution concentration, etc.) on the growth of ferroelectric PbTiO3 films by pulsed liquid injection MOCVD was examined. Pb(thd)2 and Ti(OiPr)2(thd)2 (thd=2,2,6,6-tetramethyl-3,5-heptanedionate) dissolved in toluene were used as precursors. Films were grown on LaAlO3 (001) substrates for deposition process optimisation. PbTiO3/La1− x Sr x MnO3/LaAlO3 heterostructures were elaborated at optimized deposition conditions. The microstructure of the heterostructures was characterized by X-ray Diffraction and by Raman spectroscopy. Pt/PbTiO3/La1− x Sr x MnO3/LaAlO3 structures were used for ferroelectric, dielectric and piezoelectric characterisations of PbTiO3 films. [Copyright &y& Elsevier]