Dynamic Tuning between a Reflecting Mirror and a Transmitting Window by Nano Sphere Lithography and Electrochemistry

In the ever-evolving landscape of technology, electronic devices such as displays, solar panels, and touchscreens have become indispensable to our daily lives. These devices rely on a critical component known as transparent conductive electrodes. In the past, indium tin oxide (ITO) was the common material for these electrodes. However, ITO has certain drawbacks. Its inherent oxide nature makes it brittle and susceptible to damage, and indium is a precious metal, with high cost. To overcome these challenges, researchers have explored novel nanostructures that serve as alternatives to traditional ITO electrodes. Yet, most of these nanostructures come with a drawback, i.e., they tend to possess fixed conductivity and transmittance values after production, lacking the ability for dynamic modulation.<br/>To address this limitation, in this work, we combines nanosphere lithography, indium tin oxide deposition, and the electrodeposition of silver to design and fabricate a dynamic tuning between a reflecting mirror and a transmitting window. To fabricate such a device, first of all, we spin-coated polystyrene nanopheres for a uniform mask. The corresponding spacing among nanospheres was further modified by reactive ion etching. Next, ITO was deposited to form a countinous hollow hole array. Then, the electroplating of silver was carried out. By contronling parameters of electrochemical reaction, we could fint tune the corresponding thickness of silver and the open of the hole array for actively manipulation of transmittance of the proposed devices. The electroplating behavior of th device and the transmittance for different thickness and morphology of the device were further predicted by two simulations. The first simulation focused on the transmittance of the proposed device by tuning the periodicity and the opening of the devices and the thicknesses of both ITO and silver. The second simulation involves the electrochemistry reaction. The potential variables included material parameters of electrodes and electrolytes, applied current, electrodeposition area, and thickness to anticipate the experimental outcomes.