Orthogonal‐Stacking Integration of Highly Conductive Silicide Nanowire Network as Flexible and Transparent Thin Films

Abstract

Abstract Flexible and transparent conductive (FTC) thin films are indispensable elements in building high‐performance flexible or soft electronics and displays. Slim inorganic nanowires (NWs), with excellent conductivity and durability, are ideal one‐dimensional ingredients to weave a quasi‐continuous FTC network. However, a precise spatial arrangement of these ultrathin NWs, to form an optimal interconnected network, represents still a difficult challenge. In this work, a catalytic growth of orderly SiNW arrays, via an in‐plane solid‐liquid‐solid mechanism, and an orthogonal‐stacking integration of the SiNWs into a 2‐layer cross‐linked network, followed by a direct alloy formation and soldering of highly conductive SiNi alloy NWs upon a flexible polyimide polymer, is demonstrated. It is also shown that the flexibility of the SiNi FTC network can be significantly enhanced with an elastic spring design of the silicide NW channels, leading to an impressive transmittance of ≈90%, a moderately equivalent sheet resistance of 130 Ω sq−1 and a durable flexibility that can sustain repetitive bending to a 2 mm radius for >1000 cycles. These results highlight the unique capabilities of an optimal spatial arrangement, precise assembly/soldering and elastic geometry design of alloy NWs to enable a new generation of high‐performance FTC thin film material for future flexible electronics, displays, and bio‐interfaced sensors.

Keywords

• conductive thin films
• flexible electronics
• silicide nanowires
• transparent thin films