Metal-organic frameworks (MOFs) offer disruptive potential in micro- and optoelectronics because of their chemical versatility and high porosity. For instance, the low dielectric constant (low-k) resulting from their porosity makes MOFs competitive candidates for high-performance insulators in future microchips. Both the MOF and microelectronics communities have been striving towards integrating MOFs in microchips, which requires two key engineering steps: thin film deposition and lithographic patterning. However, conventional lithography techniques use a sacrificial layer, so-called photoresist, to transfer a pattern into the desired material. The use of photoresist complicates the process, and might induce contamination of the highly porous MOF films.
A group of researchers from KU Leuven (Belgium) coordinated by Rob Ameloot has used the deep X-ray lithography (DXRL) beamline at Elettra to demonstrate that MOFs can be patterned by X-ray lithography without the use of resist layer. The method is based on selective X-ray exposure of the MOF film, which induces chemical changes that enable its removal by a common solvent. This process completely avoids the resist layer, thus significantly simplifying patterning while maintaining the physicochemical properties of patterned MOFs intact.
Read more on the Elettra website