Integrating metal-organic frameworks (MOFs) in microelectronics has disruptive potential because of the unique properties of these microporous crystalline materials. Nanoscale patterning is a fundamental step in the implementation of MOFs in miniaturised solid-state devices. Conventional MOF patterning methods suffer from a low resolution and poorly defined pattern edges. Here, we demonstrate for the first time resist-free, direct X-ray and e-beam lithography of MOFs. This process avoids etching damage and contamination, and leaves the porosity and crystallinity of the patterned MOFs intact. The resulting highquality patterns have a record sub-50 nm resolution, far beyond the state of the art in MOF patterning and approaching the mesopore regime. The excellent compatibility of X-ray and e-beam lithography with existing microfabrication processes, both in research and production facilities, provides an avenue to explore the integration of MOFs in microelectronics further. This approach is the first example of direct lithography of any type of microporous crystalline network solid, and marks an important milestone in the processing of such materials.

In this work, the influence of the iron oxide acid−base properties on the adsorption of model epoxy compounds was examined. To study this, iron oxide layers with a different surface hydroxyl fractions were prepared in controllable and reproducible conditions. The surfaces were characterized by X-ray photoelectron spectroscopy (XPS). An expression for the hydroxyl fraction of the oxide films was deduced, starting from the measured XPS intensities. Two model epoxy compounds characteristic of an epoxy/amide system were adsorbed on the oxides:  N,N‘-dimethylsuccinamide and N-methyldiethanolamine. Additionally, an amine molecule without alcohol groups, N,N‘-diethylmethylamine, was adsorbed to investigate the role of alcohol functionalities on the amine adsorption mechanism. The interaction between the oxide layers and the nitrogenous model compounds were studied by examination of the O 1s and N 1s XPS photopeaks. The data showed that the amine and amide nitrogen adsorbed via two different bonding modes:  via Lewis-like acid−base interactions and via Bronsted-like interactions or protonation. A direct correlation was found between the protonation level of the adsorbed nitrogenous molecules and the hydroxyl fraction in the outer oxide layer. Additionally, it was noted that the protonation level depended on the mobility and flexibility of the adsorbed molecules. It was also observed that the presence of alcohol groups in the amine molecular chain had a beneficial effect on the number of adsorbed amine molecules.

Robust and scalable thin film deposition methods are key to realize the potential of metal-organic frameworks (MOFs) in electronic devices. Here, we report the first integration of the chemical vapor deposition (CVD) of MOF coatings in a custom reactor within a cleanroom setting. As a test case, the MOF-CVD conditions for ZIF-8 are optimized to enable smooth, pinhole-free, and uniform thin films on full 200 mm wafers under mild conditions. The single-chamber MOF-CVD process and the impact of the deposition parameters are elucidated via a combination of in situ monitoring and ex situ characterization. The resulting process guidelines will pave the way for new MOF-CVD formulations and a plethora of MOF-based devices. Apart from their applications in catalysis, 1 gas storage, 2 and separation processes, 3 metal-organic frameworks (MOFs), with their unprecedented specific surface areas and chemical modularity, show tremendous potential for integration in microelectronics. 4,5 As sensor coatings, their tunable composition and crystalline structure can be exploited for the selective adsorption of target molecules. 6-9 The low dielectric constant resulting from their porosity makes MOFs prime candidates for high-performance insulators in future logic processors. 10,11 To capitalize on the 10-6 cm 2 , were estimated using a CCD camera. All instruments were controlled using custom software. The generated current density (J) histograms were fitted using Gaussian functions for determining the peak center and width.

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Vapour-phase deposition of copper dicarboxylate metal–organic framework thin films with an out-of-plane orientation and accessible porosity.