A Process‐Structure Investigation of Aluminum Oxide and Oxycarbide Thin Films prepared by Direct Liquid Injection CVD of Dimethylaluminum Isopropoxide (DMAI)

Abstract

We present the direct liquid injection CVD of aluminum oxide and oxycarbide thin films using dimethylaluminum isopropoxide at high process temperature (500-700 8C) with the addition of O 2 gas, and at low temperature (150-300 8C) with the addition of H 2 O vapor. Very smooth films with typical roughness values lower than 2 nm are obtained. The thin films are composed of an amorphous material. The composition evolves as a function of temperature from that of a partial hydroxide to a stoichiometric oxide at low deposition temperature (150-300 8C), and from that of a stoichiometric oxide to a mixture of an oxide with an (oxy) carbide at higher temperature (500-700 8C).

Atomic scale structure of amorphous aluminum oxyhydroxide, oxide and oxycarbide films probed by very high field27Al nuclear magnetic resonance

“…S1, ESI †). 17 In contrast, the films obtained from DLI ATI show a columnar growth of agglomerated nodules. 20 This microstructure contrasts strikingly with the one observed for films grown using evaporated ATI suggesting that the solvent (cyclohexane) used in DLI plays an important role in the nucleation and growth of the film.…”

“…14 Alternatively to evaporated ATI, another CVD process to synthesize amorphous alumina films was investigated by using the direct liquid injection (DLI) technology with ATI or dimethylaluminum isopropoxide (DMAI). [17][18][19][20] DMAI is an alumina CVD precursor which has several advantages over ATI such as a significantly higher vapor pressure; it is liquid at room temperature, has a long shelf-life and allows processing of alumina films at T d as low as 150 1C. 17,18,21 Scanning electron microscopy (SEM) and elemental analyses (electron probe micro analysis, EPMA and X-ray photoelectron spectroscopy, XPS) of the amorphous alumina films revealed different microstructures and chemical compositions depending on both the nature of the precursor and the deposition temperature.…”

“…Note that the reported C concentration is for C atoms bonded to Al only, excluding measured aliphatic C-C and C-H residues. 17,18 For EPMA, each sample was measured at least 6 times in different locations to check the homogeneity of the composition. Samples measured with XPS were eroded by about 100 nm prior to the measurement.…”

Nanocomposite thin film of Ag nanoparticles embedded in amorphous Al 2 O 3 on optical sensors windows: Synthesis, characterization and targeted application towards transparency and anti-biofouling

“…The authors group has developed various chemical vapor deposition, CVD processes for the production of amorphous alumina, a-Al 2 O 3 films [13][14][15]. Such films, processed from aluminum tri-isopropoxide, ATI contain a large percentage of penta-coordinated Al 3+ ions, as was demonstrated by 27 Al nuclear magnetic resonance, NMR spectroscopy [16].…”

Amorphous Alumina Films Efficiently Protect Ti6242S against Oxidation and Allow Operation above 600 °C

“…In short, Ti6242S coupons are placed on a stainless steel holder in the center of the quartz tube where the temperature is uniform, with a total reaction pressure of 5 Torr and a temperature of 500 °C unless otherwise mentioned. DMAI (>99%, Air Liquide) is transported to the deposition area with a direct liquid injection (DLI) technology (Kemstream), following a protocol described in details in [12]. The protocol consists in preparing a 0.2 M solution of DMAI in anhydrous cyclohexane (99.5%, H 2 O<10 ppm, Sigma-Aldrich) without any contact with the air.…”