Methyl-methacrylate based aluminum hybrid film grown via three-precursor molecular layer deposition

Molecular layer deposition (MLD) processes involving two precursors are commonly employed for the growth of conformal thin films. However, the use of two precursors limits the combinations of material properties that can be accessed during film synthesis. Here, we develop a robust, three-precursor MLD process for a hybrid film that incorporates a desirable acrylate, methyl-methacrylate (MMA), together with aluminum into its repeating structure. We report a film growth rate of 3.5 Å/cycle at 110 °C, constant growth per cycle between 100 and 130 °C, and good stability of the film when exposed to ambient. We propose reaction pathways for the incorporation of MMA into the film, and by using infrared spectroscopy and x-ray photoelectron spectroscopy, we identify the reaction pathway as a non-zwitterionic aminoacrylate reaction. This study offers new insight into the use of more than two precursors in the design of an acrylate-based MLD film and provides a framework that can be adopted for subsequent three-precursor film designs.