Bottom-Up Nanofabrication with Extreme-Ultraviolet Light: Metal-Organic Frameworks on Patterned Monolayers

Nanoscale Resist-Free Patterning of Halogenated Zeolitic Imidazolate Frameworks by Extreme UV Lithography

Advancements in patterning techniques for metal-organic frameworks (MOFs) are crucial for their integration into microelectronics. However, achieving precise nanoscale control of MOF structures remains challenging. In this work, a resist-free method for patterning MOFs is demonstrated using extreme ultraviolet (EUV) lithography with a resolution of 40 nm. The role of halogen atoms in the linker and the effect of humidity are analyzed through in situ and near-ambient pressure synchrotron X-ray photoelectron spectroscopy. In addition to facilitating the integration of MOFs, the results offer valuable insights for developing the highly sought-after positive-tone EUV photoresists.

Boronic acid functionalized of covalent organic framework for high performance capture of trace phthalates

In order to improve the enrichment performance of parent covalent organic frameworks (COFs), boronic acid functionalized of COF (COF-B(OH)2) was obtained by a simple standing method for the first time. The obtained COF-B(OH)2 exhibited the new characteristics that were not possessed by pure COF and was employed as the solid phase microextraction (SPME) coating material for highly efficient enrichment of trace endocrine disruptors phthalates (PAEs). Compared to pure COF, the synergistic effect of the newly emerged unique pore structure and boric acid interaction sites, and the large specific surface area and the abundant benzene ring structure inherited by original COF framework endowed COF-B(OH)2 with enhanced enrichment performance for PAEs. Combined with gas chromatography-mass spectrometry (GC-MS), COF-B(OH)2 exhibited the good linearity over a wide concentration of 0.1-3000 ng l-1 with good coefficients (R2, 0.9916-0.9998) for PAEs. The developed method was successfully employed for detection of trace PAEs in milk and water samples, demonstrating high recoveries (90.6-111.3 %). This work provides a sustainable approach to developing high-performance materials for enriching environmental pollutants.

Resistless EUV lithography: Photon-induced oxide patterning on silicon

In this work, we show the feasibility of extreme ultraviolet (EUV) patterning on an HF-treated silicon (100) surface in the absence of a photoresist. EUV lithography is the leading lithography technique in semiconductor manufacturing due to its high resolution and throughput, but future progress in resolution can be hampered because of the inherent limitations of the resists. We show that EUV photons can induce surface reactions on a partially hydrogen-terminated silicon surface and assist the growth of an oxide layer, which serves as an etch mask. This mechanism is different from the hydrogen desorption in scanning tunneling microscopy-based lithography. We achieve silicon dioxide/silicon gratings with 75-nanometer half-pitch and 31-nanometer height, demonstrating the efficacy of the method and the feasibility of patterning with EUV lithography without the use of a photoresist. Further development of the resistless EUV lithography method can be a viable approach to nanometer-scale lithography by overcoming the inherent resolution and roughness limitations of photoresist materials.

Advances in Metal-organic Frameworks (MOFs) based Biosensors for Diagnosis: An Update

Metal-organic frameworks (MOFs) have significant advantages over other candidate classes of chemo-sensory materials owing to their extraordinary structural tunability and characteristics. MOF-based biosensing is a simple and convenient method for identifying various species. Biomarkers are molecular or cellular processes that link environmental exposure to a health outcome. Biomarkers are important in understanding the links between environmental chemical exposure and the development of chronic diseases, as well as in identifying disease-prone subgroups. Until now, several species, including nanoparticles (NPs) and their nanocomposites, small molecules, and unique complex systems, have been used for the chemical sensing of biomarkers. Following the overview of the field, we discussed the various fabrication methods for MOFs development in this review. We provide a thorough overview of the previous five years of progress to broaden the scope of analytes for future research. Several enzymatic and non-enzymatic sensors are offered, together with a mandatory measuring method that includes detection range and dynamic range. In addition, we reviewed the comparison of enzymatic and non-enzymatic biosensors, inventive edges, and the difficulties that need to be solved. This work might open up new possibilities for material production, sensor development, medical diagnostics, and other sensing fields.