Maskless metal patterning by meniscus-confined electrochemical etching and its application in organic field-effect transistors

Dynamic Electrolyte Spreading during Meniscus-Confined Electrodeposition and Electrodissolution of Copper for Surface Patterning

“…The results show that the electrodissolution, when done at a higher voltage or for a longer time, will lead to a greater degree of spreading and, thereby, a higher deviation from the expected pattern size (from the assumption of a nonspreading meniscus). Our results are in consonance with the earlier literature observations where a larger pattern size was observed during the meniscus-confined electrodissolution when a higher voltage was applied or when the pipette containing the counter electrode was moved slowly over the surface . Therefore, for the generation of more accurate surface patterns, the rate of droplet spreading should be taken into account, or approaches should be devised to reduce the extent of spreading.…”

“…Our results are in consonance with the earlier literature observations where a larger pattern size was observed during the meniscus-confined electrodissolution when a higher voltage was applied or when the pipette containing the counter electrode was moved slowly over the surface. 22 Therefore, for the generation of more accurate surface patterns, the rate of droplet spreading should be taken into account, or approaches should be devised to reduce the extent of spreading. Further, by changing the surface properties, new patterns can be generated such as the annular ring-shaped pattern through dynamic spreading, shown here using a superhydrophobic surface.…”

“…), using microelectrodes coupled with small interelectrode distances, laser-assisted electrochemical approach, selective deposition through irradiated self-assembled monolayers, liquid meniscus-confined electrodeposition/electrodissolution, etc. − Among these localized electrochemical approaches, employing the liquid meniscus to confine the zone of electrodeposition or electrodissolution has recently been identified as a facile maskless approach for the micromachining of metals and semiconductors to form controlled patterns and 3D-structures. ,− Such patterns and structures are usually created by placing a small electrolyte droplet on the surface of interest with a counter electrode, often with a micropipette for continuous dispensing of the electrolyte. Depending on the polarity of the applied electric potential, the electrodeposition or electrodissolution occurs on the solid–liquid (SL) interfacial area confined by the liquid meniscus. ,, This causes the deposition or dissolution-induced microstructure change only under the droplet, while the area outside the meniscus remains unaltered which allows for controlled surface patterns and complex 3D microstructures. While the focus until now in these meniscus-confined approaches has been on creating different types of microstructures and developing tools for them, the effect of the surface properties and whether the electrochemical reactions have any impact on the meniscus shape has not been explored.…”

“…Depending on the polarity of the applied electric potential, the electrodeposition or electrodissolution occurs on the solid−liquid (SL) interfacial area confined by the liquid meniscus. 10,13,22 This causes the deposition or dissolution-induced microstructure change only under the droplet, while the area outside the meniscus remains unaltered which allows for controlled surface patterns and complex 3D microstructures. While the focus until now in these meniscus-confined approaches has been on creating different types of microstructures and developing tools for them, the effect of the surface properties and whether the electrochemical reactions have any impact on the meniscus shape has not been explored.…”

Smart batteries enabled by implanted flexible sensors

“…116 Of these technologies, photolithography performs an important role in sensing electrode design on the chip level. Two kinds of lithography techniques are studied: mask-based 117,118 and maskless 119,120 techniques. For large-scale production, maskbased lithography is mainly considered, including contact and noncontact modes.…”