Fundamental Performance Limits and Haze Evaluation of Metal Nanomesh Transparent Conductors

Abstract

Metal nanomeshes are demonstrated as flexible transparent conductors with performance comparable to indium tin oxide. However, it is not known what the performance limits of these structures are in terms of transparency and sheet resistance. More importantly, the haze, which describes how much incident light is scattered by these structures, has not been studied. In this paper, the transmission, sheet resistance, and haze of metal nanomeshes are comprehensively studied to determine their fundamental performance limits as transparent conductors through simulations and experiments. Numerical simulations and analytical calculations are used to evaluate the tradeoffs and correlations between these three figures of merit. A strong correlation is found between haze and transmission, where structures with high transmission tend to have low haze and vice versa. Structures with a pitch above 1000 nm are beneficial for achieving transmission over 80% and larger thickness is favorable in reducing sheet resistance without significantly affecting transmission. Furthermore, metal nanomeshes are fabricated to verify simulation results. The haze may be primarily explained by Fraunhofer diffraction, but the spectral dependence of haze requires analysis with Mie scattering theory. The results should apply to all metal grid or grating‐like structures. The fundamental performance limits evaluated here are helpful for guiding engineering design and research prioritization.

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