Aerosol‐Assisted Chemical Vapour Deposition of a Copper Gallium Oxide Spinel

Abstract

Copper‐based spinel oxide CuGa2O4 films have been deposited by means of a simple one‐pot solution‐based chemical vapour deposition (CVD) method. Aerosol‐assisted (AA) CVD of copper(II) 2,2,6,6,‐tetramethylheptan‐3,5‐dionate (thd), Cu(thd)2 and gallium(III) acetylacetonate, Ga(acac)3, in toluene resulted in the formation of transparent films with a slight yellow tinge at 300–500 °C. Scanning electron microscopy (SEM) indicated that the films had grown by means of an island growth mechanism. Energy‐dispersive X‐ray (EDX) analysis and X‐ray photoelectron spectroscopy (XPS) showed that CuGa2O4 had formed along with copper(I) oxide and gallium(III) oxide was observed at the surface of the film. Annealing the films under a range of conditions (air, N2, vacuum) resulted in oxidation and the formation of CuGa2O4 and copper(II) oxide, as shown by powder X‐ray diffraction (XRD). The films were further analysed by UV/Vis spectroscopy and atomic force microscopy. Similar AACVD depositions using copper(II) acetylacetonate, Cu(acac)2, and Ga(acac)3 in a range of solvents only resulted in the formation of gallium oxide owing to the lower solubility of the copper precursor than the gallium complex. AACVD is dependent on the precursor solubility hence Cu(thd)2 is a superior precursor to Cu(acac)2 owing to its increased solubility.

Ga2O3–Cu2O: synthesis, characterisation and antibacterial properties

“…There was no evidence for the formation of the spinel phase that has previously been isolated for AACVD synthesized Ga 2 O 3 and CuO composite lms when annealed under vacuum. 21 As a result, further discussion in this manuscript will focus solely on the amorphous asdeposited lms of pure Ga 2 O 3 and composite Ga 2 O 3 -Cu 2 O.…”

MODs vs. NPs: Vying for the Future of Printed Electronics

“…Inspired by the Ag atomic layer deposition field, Black et al used the metal-organic compound: [(hfac)(1,5-COD)Ag] (where hfac = hexafluoroacetylacetone) in their MOD ink. Acetylacetones [37] and their fluorinated counterparts are commonly found in vapour deposition techniques of metals and metal oxide, [38,39] but are rarely used in MOD ink chemistry. The hfac compound was dissolved in anhydrous toluene followed by the addition of isopropanol under inert conditions, producing a series of inks with varying organometallic/alcohol ink ratios.…”

Solution based CVD of main group materials

“…[156][157][158] Accessible through facile synthetic routes, 159 Recently, the use of these precursors for the deposition of spinel materials via AACVD has been reported. 162,163 However, attempts to synthesise compounds of the type [GaX(O 2 {R}) 2 ] (X = Cl, Me, H) for use in CVD failed and this further evidenced the thermodynamic stability of the homoleptic tris(b-diketonates) which formed instead. 164 Despite excellent solubility, the stability of gallium b-diketonates has meant that they are not ideal precursors for use in AACVD.…”