Optically-controlled digital electrodeposition of thin-film metals for fabrication of nano-devices

Precise micro-scale patterning of metal thin-films with semiconductor materials is a critical step in the fabrication of any micro-devices. Conventional metal patterning methods such as photolithography, laser-induced direct printing techniques, and micro-contact printing methods all have different disadvantages such as high capital equipment cost and low throughput efficiency. In this article, an optically-controlled digital electrodeposition (ODE) method for direct patterning of metal thin-films on a semiconductor substrate has been demonstrated. This method allows for dynamic patterning of custom micro-scale silver structures with high conductivity of 2 x 10(7) S/m in large scale within 10 seconds and could reach a smallest line width of 2.7 mu m. The entire process is performed at room temperature and atmospheric pressure conditions, while requiring no photolithographic steps or metal nanoparticle inks. Utilizing this direct structural formation technique, a bottom-up protocol for rapidly assembling nanowire-based field-effect transistors has been demonstrated, which shows that this novel technique could potentially become an alternative, low-cost and flexible technology for fabricating integrated nano-devices. (C) 2015 Optical Society of Americ