High-Uniformity, Shape-Controlled Silicon Nanowires for Enhanced Performance in Optoelectronic Devices.

Silicon nanowires (Si NWs) have attracted considerable interest owing to their distinctive properties, which render them promising candidates for a wide range of advanced applications in electronics, photonics, energy storage, and sensing. However, challenges in achieving large-scale production, high uniformity, and shape control limit their practical use. This study presents a novel fabrication approach combining nanoimprint lithography, nanotransfer printing, and metal-assisted chemical etching to produce highly uniform and shape-controlled Si NW arrays. By optimizing the process parameters, Si NWs with various diameters (100, 200, and 400 nm) are successfully fabricated on 6-inch wafers, achieving high uniformity confirmed through statistical and surface reflection analyses. Furthermore, a conformal coating of titanium nitride on the uniform Si NWs enables broadband absorption with average absorption of 75% in the wavelength range from 250 to 2500 nm, demonstrating their potential for next-generation optoelectronic devices. These findings provide valuable insights for the scalable production of Si NWs and their integration into high-performance electronic systems.