This is an open access article published by the IET under the Creative Commons Attribution -NonCommercial License (http://creativecommons.org/licenses/by-nc/3.0/)
The study presents the thickness effect of mesh metal films printed onto glass substrate on the shielding effectiveness (SE) of such transparent screens. Currently, standards in microelectronic technology use a metal film thickness of between ∼100 nm and few micrometres, depending on the available deposition and implementation techniques. This study demonstrates that the thickness of mesh metal films is a key parameter which needs to be adjusted precisely. A theoretical model based on SE, complex impedance and optical transparency has been developed for this purpose. At microwaves, a relevant selection of the metal thickness values from 0.1 to 2 µm changes the SE at low frequency (from 36 to 40 dB at 2 GHz, respectively) while maintaining it constantly at a higher frequency (close to 20 dB at 18 GHz). The optical transparency of such mesh screens is kept constant over the entire visible light spectrum (78%). Experimental data are in complete agreement with the theoretical values.
References
-
-
1)
-
2. Lu, Z., Wang, H., Tan, J., et al: ‘Microwave shielding enhancement of high-transparency, double-layer, submillimeter period metallic mesh’, Appl. Phys. Lett., 2014, 105, p. 241904, (doi: 10.1063/1.4904466).
-
2)
-
2. Hecht, D.S., Hu, L., Irvin, G.: ‘Emerging transparent electrodes based on thin films of carbon nanotubes, graphene, and metallic nanostructures’, Adv. Mater., 2011, 23, (13), pp. 1482–1513 (doi: 10.1002/adma.201003188).
-
3)
-
6. Corredores, Y., Besnier, P., Castel, X., et al: ‘Adjustment of shielding effectiveness, optical transmission and sheet resistance of conducting films deposited on glass substrates’, IEEE Trans. Electromagn. Compat., 2017, 59, (4), pp. 1070–1078, (doi: 10.1109/TEMC.2017.2654269).
-
4)
-
3. Liu, Y., Tan, J.: ‘Frequency dependent model of sheet resistance and effect analysis on shielding effectiveness of transparent conductive mesh coatings’, Prog. Electromagn. Res., 2013, 140, pp. 353–368, (doi: 10.2528/PIER13050312).
-
5)
-
4. Ulrich, R.: ‘Far-infrared properties of metallic mesh and its complementary structure’, Infrared Phys., 1967, 7, (1), pp. 37–55, (doi: 10.1016/0020-0891(67)90028-0).
-
6)
-
5. Whitbourn, L.B., Compton, R.C.: ‘Equivalent-circuit formulas for metal grid reflectors at a dielectric boundary’, Appl. Opt., 1985, 24, (2), pp. 217–220, (doi: 10.1364/AO.24.000217).
http://iet.metastore.ingenta.com/content/journals/10.1049/joe.2018.0070
Related content
content/journals/10.1049/joe.2018.0070
pub_keyword,iet_inspecKeyword,pub_concept
6
6
SE adjustment of planar mesh screen by fine-tuning metal thickness