In Situ Atomic/Molecular Layer-by-Layer Deposition of Inorganic–Organic Coordination Network Thin Films from Gaseous Precursors

Abstract

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.

Lithium Aryloxide Thin Films with Guest‐Induced Structural Transformation by ALD/MLD

“…Regarding the crystallization of ALD/MLD samples, it is interesting to note that including the present findings, all the reported ALD/MLD processes for s‐block metals have yielded crystalline thin films over wide temperature windows, whereas the transition‐metal‐ and aluminium‐based processes, with the exception of Cu‐terephthalate, have resulted in amorphous thin films. The s‐block metals are known to form mainly ionic compounds with organic constituents .…”

“…Thus, understanding the conditions leading to well‐crystallized inorganic–organic thin films is a key requirement on the road to gas‐phase deposition of porous CP thin films. In our very recent ALD/MLD works, we have indeed been able to deposit in situ crystalline (but not necessarily porous) inorganic–organic thin films with several different precursor combinations . Well‐crystalline films were obtained with the s‐block metals Ca and Li over a wide temperature range when combined with 1,4‐benzenedicarboxylic acid as the organic component.…”

Atomic/Molecular Layer Deposition of s‐Block Metal Carboxylate Coordination Network Thin Films

“…Hybrid inorganic–organic thin films of aromatic carboxylic acid precursors have indeed been deposited by ALD/MLD, but the majority of the films have been amorphous . Very recently, we succeeded in growing the first in situ crystalline ALD/MLD thin films . In these crystalline hybrid thin films the metal constituents were copper, calcium, lithium and sodium, and in the first three cases the organic precursor was terephthalic acid.…”

Atomic/Molecular Layer Deposited Iron–Azobenzene Framework Thin Films for Stimuli‐Induced Gas Molecule Capture/Release

“…[25] In ALD/MLD the metal-organic material is grown from two mutually reactive gaseous precursors sequentially pulsed into the reactor chamber with an intermediate inert-gas purging step.L ike in the case of the parent ALD (atomic layer deposition) technology for simple inorganic materials,t his results in self-limited gas-surface reactions and consequently in the atomic/molecular level control of the growing thin-film material on the chosen substrate surface. [28][29][30][31] Herein we report the ALD/MLD growth of crystalline iron-azobenzene thin films in which the azobenzene moieties are an integral part of the crystal framework. [28][29][30][31] Herein we report the ALD/MLD growth of crystalline iron-azobenzene thin films in which the azobenzene moieties are an integral part of the crystal framework.…”