Gallium Hydride Complexes Stabilised by Multidentate Alkoxide Ligands: Precursors to Thin Films of Ga₂O₃ at Low Temperatures

Abstract

The donor‐functionalised alkoxides {Me3−xN(CH2CH2O)x} (Lx; x=1, 2) have been used to form gallium hydride complexes [{GaH2(L1)}2] and [{GaH(L2)}2] that are stable and isolable at room temperature. Along with a heteroleptic gallium tris(alkoxide) complex [Ga(L1)3] and the dimeric complex [{GaMe(L2)}2], these compounds have been used as single‐source precursors for the deposition of Ga2O3 by aerosol‐assisted chemical vapour deposition (AACVD) with toluene as solvent. The resulting films were mostly transparent, indicating low levels of carbon contamination, and they were also mainly amorphous. However, [Ga(L1)3] did contain visibly crystalline material deposited at a substrate temperature of 450 °C, by far the lowest ever observed for the CVD of gallium oxide.

Alternative Precursors for the Synthesis of Binary Sb2E3 and Bi2E3 (E = S, Se, Te) Nanoparticles by the Hot Injection Method

“…In contrast, the amino‐functionalized bismuth alkoxide Bi[OC(CH 2 NMe 2 ) 3 ] 3 shows a six‐coordinate bismuth atom with a fac , fac ‐BiO 3 N 3 coordination sphere . Moreover, the structures of several other main‐group metal complexes containing the amino alkoxide ligand have been reported, including that of Ga(OCH 2 CH 2 NMe 2 ) 3 . Unfortunately, the poor quality of the crystals only allowed for the description of the atom connectivity, but showed the formation of a monomeric tris(alkoxide), which was somewhat surprising since, on the basis of mass spectrometric studies, the compound was reported previously to adopt a dimeric, oxygen‐bridged structure, as was also observed for the corresponding indium tris(alkoxide) In(OCH 2 CH 2 NMe 2 ) 3 .…”

Synthesis and Structural Characterization of β‐Ketoiminate‐Stabilized Gallium Hydrides for Chemical Vapor Deposition Applications

“…Initial characterisation of 8 was carried out by 1 H NMR spectroscopy, with the formation of the hydride being indicated by the absence of any NH proton of the pro‐ligand and by the presence of a very broad singlet at 5.83 ppm. This peak broadening is due to the two quadrupolar gallium nuclei, 69 Ga and 71 Ga, with I= 3 / 2 and is characteristic of hydrogen atoms forming terminal bonds to gallium 23c. 32 IR spectroscopic analysis showed a broad band at 1867 cm −1 , characteristic of a GaH stretch 23a…”

Investigations into the structure, reactivity, and AACVD of aluminium and gallium amidoenoate complexes

“…However, the acid-base reaction between HAME Dip and [GaH 3 (NMe 3 )] resulted in no observable hydrogen evolution and eventually, decomposition of the gallium hydride to gallium metal occurred. Despite [GaH 3 (NMe 3 )] being a successful synthon for the isolation of other {Ga-H} containing precursors we have reported previously, such as [GaH(NMe 3-x {CH 2 CH 2 O} x ) 2 ], 48,49 the aminestabilized gallane employed was not found to react with the aminoenoate pro-ligand. Despite the various temperature and solvent conditions attempted (which included keeping the reaction mixture at 0 °C for 12 hours, or using various solvents including toluene, hexane and diethyl ether), a gallium hydride bis-amidoenoate complex could not be isolated via this route.…”