Atomic/molecular layer deposition of Ni-terephthalate thin films

We acknowledge the funding from Academy of Finland (Profi 3), and the use of the RawMatTERS Finland Infrastructure (RAMI) at Aalto University. The measured data of RIXS will be available for public after three years period following DOI: 10.15151/ESRF-ES-438677278.Atomic/molecular layer deposition (ALD/MLD) is currently strongly emerging as an intriguing route for novel metal–organic thin-film materials. This approach already covers a variety of metal and organic components, and potential applications related to e.g. sustainable energy technologies. Among the 3d metal components, nickel has remained unexplored so far. Here we report a robust and efficient ALD/MLD process for the growth of high-quality nickel terephthalate thin films. The films are deposited from Ni(thd)2 (thd: 2,2,6,6-tetramethyl-3,5-heptanedionate) and terephthalic acid (1,4-benzenedicarboxylic acid) precursors in the temperature range of 180–280 °C, with appreciably high growth rates up to 2.3 Å per cycle at 200 °C. The films are amorphous but the local structure and chemical state of the films are addressed based on XRR, FTIR and RIXS techniques.Peer reviewe