| Abstract
| - We have investigated the reaction of trimethylaluminum (TMA) with −CH3, −OH, and −COOH terminatedself-assembled monolayers (SAMs) adsorbed on Au, using time-of-flight secondary ion mass spectrometryand X-ray photoelectron spectroscopy. TMA is a well-known atomic layer deposition precursor that is employedcommercially to deposit compound semiconductors, alumina, and nitrides. We demonstrate that TMA can beemployed to deposit both alumina and aluminum on SAMs at room temperature. TMA reacts with −OH and−COOH terminated SAMs to form a surface-bound dimethyl aluminum complex but does not react with−CH3 terminal groups. If deposition is performed in a nitrogen-purged glovebox, an alumina film is grownon −CH3, −OH and −COOH terminated SAMs. The alumina film can be removed from −CH3 terminatedSAMs by rinsing with organic solvents. However if the base pressure of the deposition chamber is below10-8 Torr, a metallic Al overlayer is selectively deposited on −OH and −COOH terminated SAMs, and noreaction is observed on −CH3 terminated SAMs. Using these reactions, we demonstrate that alumina andaluminum can be selectively deposited on patterned SAMs. The possible reaction pathways involved in thefilm growth on these different surfaces are discussed.
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