Scalable Printing of Metal Nanostructures Through Superluminescent Light Projection.

Direct printing of metallic nanostructures is highly desirable but current techniques cannot achieve nanoscale resolutions or are too expensive and slow. Photoreduction of solvated metal ions into metallic nanoparticles is an attractive strategy because it is faster than deposition-based techniques. However, it is still limited by the resolution versus cost tradeoff because sub-diffraction printing of nanostructures requires high-intensity light from expensive femtosecond lasers. Here, we have overcome this tradeoff by leveraging the spatial and temporal coherence properties of low-intensity diode-based superluminescent light. We present the superluminescent light projection (SLP) technique to rapidly print sub-diffraction nanostructures, as small as 210 nm and at periods as small as 300 nm, with light that is a billion times less intense than femtosecond lasers. We demonstrate printing of arbitrarily complex 2D nanostructured silver patterns over 30 μm × 80 μm areas in 500 ms time scales. The post-annealed nanostructures exhibit an electrical conductivity up to 1/12 th that of bulk silver. SLP is up to 480 times faster and 35 times less expensive than printing with femtosecond lasers. Therefore, it transforms nanoscale metal printing into a scalable format, thereby significantly enhancing the transition of nano-enabled devices from research laboratories into real-world applications. This article is protected by copyright. All rights reserved.