Simulation and experimental studies are carried out on single‐layer and double‐layer embedded metal meshes (SLEMM and DLEMM) to assess their performance as transparent electromagnetic interference (EMI) shielding. The structures consist of silver meshes embedded in polyethylene terephthalate (PET). As a transparent electrode, SLEMMs exhibit a transparency of 82.7% and a sheet resistance of 0.61 Ωsq−1as well as 91.0% and 1.49 Ωsq−1. This performance corresponds to figures of merit of 3101 and 2620, respectively. The SLEMMs achieve 48.0 dB EMI shielding efficiency (SE) in the frequency range of 8–18 GHz (X‐ and Ku‐bands) with 91% visible transmission and 56.2 dB EMI SE with 82.7% visible transmission. Samples exhibit stable performance after 1000 bending cycles with a radius of curvature of 4 mm and 60 tape test cycles. DLEMMs consist of fabricating SLEMM on opposite sides of the substrate where the distance can be varied using a spacer. Simulations are performed to investigate how varying spacer distance between two layers of metal meshes influences the EMI SE. DLEMMs are fabricated and achieved an EMI SE of 77.7 dB with 81.7% visible transmission. SLEMMs and DLEMMs may have a wide variety of applications in aerospace, medical, and military applications.
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.
more » « less- PAR ID:
- 10054398
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 6
- Issue:
- 9
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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