Interdependence of resistance and optical transmission in conductive nanowire networks

Metallic nanowire networks show great potential for use in transparent conductive displays. The coupled relationship between the principal materials properties of interest for such applications, optical transmittance and sheet resistance, is known to be affected by both nanowire dimensions and area coverage. Existing theory to describe the observed interdependence requires consideration of both bulk and surface phases.

Here, we present an analysis of structural variables in these materials confirming that bulk considerations do not typically apply. Accordingly, we develop a model using statistical theory for random line networks that requires consideration of a surface phase only. The resultant simple expression relates sheet resistance and optical transmission of heterogeneous nanowire assemblies in terms of nanowire dimensions. Comparison of our model with experimental and simulation data from the literature shows excellent agreement. In closing, we provide theoretical insights into the observed influence on sheet resistance of poly-disperse nanowire lengths and of structural variability.