Indium (III) acetylacetonate In(acac)3 is a creamy powder melting at 187-189°C. The mass spectra of the indium (III) acetylacetonate In(acac)3 were investigated. The main decomposition pathways are similar to Ga(acac)3 and discussed in corresponding section [475]
Indium tris-acetylacetonate In(acac)3
with 5 mol % Sn (IV) bis-acetylacetonate dibromide dissolved in acetylacetone (0.2 M or 0.02 M) was applied for the growth of transparent conductive thin layers of Sn doped In2O3 (ITO) on glass substrates (Corning #1737) by Aerosol-Assisted CVD. Film electrical resistivity, carrier concentration, Hall mobility, and optical bandgap
were independent of thickness for ITO using the 0.2 M solution, with values of 1–2×10–4 Ω cm, 1–3×1021 cm–3, 20–50 cm2
V–1s–1, and 4.0∼4.1 eV, respectively. For ITO films prepared using the 0.02 M solution, the mobility decreased with increasing thickness over 50 nm, corresponding to a worsening of the film crystallinity [[i]]
[i] A. Suzuki, K. Maki, Chemical Vapor Deposition, Special Issue: Aerosol-Assisted CVD, Volume 12, Issue 10, pages 608–613, October, 2006
Indium acetylacetonate In(acac)3 and hydrogen sulphide (H2S) separate pulses were applied for the atomic layer CVD growth of indium sulfide In2S3 as buffer layers for high-efficiency Cu(In,Ga)Se2 thin-film solar cells. Optimal value deposition temperature was 220°C (in the range 160°-260°C), optimal thickness 30 nm (in the range 15–30 nm), the process efficiency was 16.4%. In2S3 buffer layers resulted in an improvement of the blue response of the cells compared with a standard CdS-processed cell, due to a high apparent band gap (2·7–2·8 eV), higher open-circuit voltages (up to 665 mV) and fill factor (78%), indicating high interface quality. [513]
Indium trifluoroacetylacetonate In(tfac)3 have been studied by mass spectrometry. The fragmentation of the molecular ion [M(tfac)3]+ happens mainly by ligand radical elimination giving ion [M(tfac)2]+ which subsequently is fragmenting via reactions involving loss of ligand fragments, similar to Ga(tfac)3[475]
Indium hexafluoroacetylacetonate In(hfac)3 is an air stable white microcrystalline solid at RT. It was synthesized in good yield by the salt elimination reaction from InCl3 and Na(hfac) followed by purification by sublimation, and characterized by NMR, IR and melting point data are as expected for In(hfac)3 .
In(hfac)3 was used as the indium precursor for the first successful CVD preparation of the chalcopyrite CuInSe2 thin layers using a glow discharge enhanced CVD process. Thin films with compositions around the Cu:In:Se stoichiometric ratio 1:1:2 were obtained; film structure was studied by X-ray camera technique and RBS.
In(hfac)3 was also reported to be used for the PECVD preparation of thin films of In and In-Cu alloys [515]
Indium tris (2,2,6,6-tetramethylheptane-3,5-dionate) [In(thd)3] has been characterised by 1H NMR spectroscopy, mass spectrometry and elemental analysis; its structure was determined by X-ray crystallography. [516]
[In(thd)3] suspended in dichloromethane CH2Cl2 was applied for the growth of thin crystalline films of In2O3 by aerosol-assisted CVD at 450 °C temperature. Poor solubility of [In(thd)3] was limiting the growth rate and thickness of the films. The films were analyzed by scanning electron microscopy (SEM), glancing angle X-ray diffraction (XRD) and energy dispersive analysis of X-rays (EDX). [516]
Indium tris(2,2,6,6-tetramethyl-3,5-heptanedionate) In(thd)3, combined with Zn(thd)2 (both dissolved
in 1,2-dimethoxyethane) was applied s In precursor for the deposition of In-doped ZnO films by aerosol-assisted MOCVD. By using ultrasound source (2.56 MHz), the solution of a precursor mixture was transformed into an aerosol, transported into the deposition
zone (with N2 + O2 carrier gas) and applied for the AACVD depositions at 350–600 °C. The influences of the substrate, deposition temperature, and doping level on the layer structural, electrical and optical properties were studied by Hall measurements,
XRD, SEM, AFM, UV–Vis and FT-IR spectroscopies. Best electrical properties were achieved for the epitaxial layers grown on R-plane sapphire. In-doped ZnO films had higher resistivity compared to Ga- and Al- doped. [[i]]
[i] S. Kuprenaite, T. Murauskas, A. Abrutis, V. Kubilius, Z. Saltyte, V. Plausinaitiene, Surf. Coat. Technology, Vol. 271, 2015, p. 156-164, https://doi.org/10.1016/j.surfcoat.2014.12.052 , https://www.sciencedirect.com/science/article/abs/pii/S0257897214011967
Properties of In-, Ga-, and Al-doped ZnO films grown by aerosol-assisted MOCVD: Influence of deposition temperature, doping level and annealing