Atomic/molecular layer deposition offers us an elegant way of fabricating crystalline copper(ii)terephthalate metal-organic framework (MOF) thin films on various substrate surfaces. The films are grown from two gaseous precursors with a digital atomic/molecular level control for the film thickness under relatively mild conditions in a simple and fast one-step process.

Crystalline inorganic-organic coordination network materials possess a property palette highly attractive for a number of frontier applications. In many prospective applications of these materials high-quality thin films would be required. Gas-phase thin-film techniques could potentially provide a number of advantages over the current liquid-phase techniques for depositing such state-of-the-art hybrid thin films. The strongly emerging atomic/molecular layer deposition (ALD/MLD) technique in particular enables the rational fabrication of inorganic-organic thin films in a digital atomic/molecular layer-by-layer manner through successive gas-to-surface reactions of inorganic and organic precursors but the resultant films have been amorphous. Here we demonstrate the in-situ ALD/MLD growth of well-crystalline calcium terephthalate (Ca-TP) coordination network thin films in a wide deposition temperature range. We moreover investigate the water absorption/desorption characteristics of the films and report attractive mechanical properties for both the dry and water-intercalated films.

International audienc

Here we report the growth of novel hybrid transition metal-organic thin-film materials consisting of manganese or cobalt as the metal component and terephthalate as the rigid organic backbone. The hybrid thin films are deposited by the currently strongly emerging atomic/molecular layer deposition (ALD/MLD) technique using the combination of metal β-diketonate, i.e. Mn(thd)3, Co(acac)3 or Co(thd)2, and terephthalic acid (1,4-benzenedicarboxylic acid) as precursors. All the processes yield homogeneous and notably smooth amorphous metal-terephthalate hybrid thin films with growth rates of 1-2 Å/cycle.The films are stable towards humidity and withstand high temperatures up to 300 or 400 °C under oxidative or reductive atmosphere, respectively. The films are characterized with XRR, AFM, GIXRD, XPS and FTIR techniques.