Long range mass transport driven by an electric field has many applications in the fields of nanoscience and technology. Liquid-phase mass transport ranging from the micrometer to the millimeter scale and its application to nanopatterning have been demonstrated on chromium (Cr) thin films using a DC electric field. Under the influence of an electric field, the metal seems to undergo a chemical reaction, and the resulting liquid material flows out radially in all directions. In this study, we have explored the effect of an alternating (AC) electric field on this kind of liquid-phase material transport. Within the scope of this work, mass transport has been studied on Cr films 30 nm thick using an alternating square waveform with frequencies ranging from 100 Hz to 1000 Hz in steps of 50 Hz. The dependence of the material’s formation, flow distance, and flow velocity on frequency, for a constant applied root mean square (RMS) voltage, was studied in detail. An analytical model is presented to explain the experimental results. This study, in particular the frequency parameter and the intermittent nature of the applied bias, will help us get a better control over the mass flow process, will lead to better resolutions for the electrolithography process.

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Electric field induced liquefaction of chromium (Cr) thin-films, being a surface-based process, is affected by the moisture content in the surroundings. The said process is an electrochemical reaction, which takes place on an electrically stressed Cr thin-film. The reaction results in a liquid region, which flows out radially from the tip of the cathode. A proper understanding of the phenomenon is warranted as it is applied for performing a nanolithography process, electrolithography (ELG). In this study we have focused on the effect of relative humidity (RH) on the material formation and transport on electrically stressed Cr thin-film. Varying the RH over a wide range, the phenomenon is studied using different levels of DC stress. The effect of the applied DC stress coupled with varying levels of RH showed trends which are explained qualitatively and quantitatively. The results indicate that RH could be a pivotal parameter affecting the above-mentioned phenomenon on electrically stressed Cr thin-films and could significantly alter the minimum feature size attainable by ELG. To demonstrate the effect of RH on ELG, lines were drawn at various humidity levels resulting in greater than 100% increase in the attainable line width when RH was increased by about 40%.

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This work demonstrates highly efficient solid‐state proton conduction in helical organic scaffolds inspired by the biomolecule gramicidin A. The scaffold, 1, derived from a pyridine‐2,6‐dicarboxamide (PDC) residue adopts a helical conformation that is stabilized by a network of strong bifurcated intramolecular H‐bonds between the polar residues that align the inner (concave) face of the molecule, while the aromatic units in 1 are oriented outwards. As a result, the helix attains an ambipolar nature just like gramicidin A. Two different solid forms of 1 could be isolated: a yellow solid from high‐polarity solvents and an orange solid from low‐polarity solvents. Single‐crystal X‐ray diffraction (SCXRD) studies showed that in the former, molecules of 1 are stacked in a homochiral fashion, while in the latter heterochiral stacks of 1 were present. The yellow form exhibited an almost ∼300‐fold higher conductivity (of up to 0.12 mS cm−1 at 95 °C and 95 % relative humidity) than the orange form as a result of closer intermolecular proximity and lower activation energy of 0.098 eV, thus indicating a Grotthus mechanism of proton transport. This study establishes the key role of bioinspired design and controlled stereo‐organization of such discrete uncharged organic molecules in achieving efficient solid‐state proton conduction.