Metallic Nanomesh with Disordered Dual-Size Apertures As Wide-Viewing-Angle Transparent Conductive Electrode

Abstract

With the rapid development of display-related markets, transparent conductive films (TCFs) with wide viewing angles, high transmittance and low sheet resistance are in high demand. However, as a promising TCF material, metallic membranes with a submicrometer-sized periodicity pattern fabricated by currently available techniques always reveal the angle-dependent structure color which can be a major issue in the development of wide-angle viewing display-related applications. In this work, we demonstrate an Au nanomesh with disordered dual-size apertures as a novel TCF with wide viewing angles which is made via a modified nanosphere lithography technique. The as-prepared Au nanomesh film shows good optoelectronic properties (Rs = 160 Ω sq(-1), T = 80%; Rs = 8 Ω sq(-1), T = 57%) that are similar to the Au nanomesh with single size apertures, while the former exhibits excellent wide-angle viewing performance. There is no obvious change in the film when the viewing angle, the light incidence angle or the orientation of substrate vary in the range of 0-90°. In contrast, a rainbow color is observed with the film with ordered single-size apertures. Electrochromic devices based on the novel metallic film show more uniform color distribution than the devices based on metallic film with ordered single-size apertures under indoor natural light irradiation. These findings demonstrate the applicability of the Au nanomesh film with dual-size apertures in enhancing display quality of high-performance optoelectronic devices.

Transparent and conductive electrodes by large-scale nano-structuring of noble metal thin-films

“…It should be mentioned that the vacuum processing steps used in our approach makes it more expensive, however, these techniques are nonetheless industry standard methods and can thus be scaled up to reduce processing cost. We postulate the fabrication cost can be reduced further by employing cheaper polydisperse particle solutions with the added benefit that the randomized particle size and thus aperture size tends to reduce iridescence of the fabricated films [16]. We further postulate that the PSP hotplate treatment, rather than cooling during etching, may sufficiently stick the PSP to the substrate so that relatively cheap barrel ashing can substitute ICP-RIE.…”

“…Polystyrene particles (PSP) have previously been used as masks for TCFs [14][15][16][17] showing promising experimental results, e.g. a way to minimize the iridescence of these films by employing polydisperse particles [16] and a way to engineer highly efficient and wavelengthselective reflectors [17]. Theoretically, however, in those works transmission is either solely experimentally determined or estimated by a simple geometric model not considering surface plasmon absorption and no theoretical analysis is presented for the TCF sheet resistance.…”

Emerging Novel Metal Electrodes for Photovoltaic Applications

“…Besides the template fabricated through photolithography, the periodic or random arranged microspheres on substrate can also act as the template for the deposition of metal film with micrometer size holes, which allow the penetration of light . Thin film with the formation of cracks inside, in most cases, is normally regarded as poor quality.…”

“…[269,270] Besides the template fabricated through photolithography, the periodic or random arranged microspheres on substrate can also act as the template for the deposition of metal film with micrometer size holes, which allow the penetration of light. [271][272][273][274][275][276][277] Thin film with the formation of cracks inside, in most cases, is normally regarded as poor quality. However, Ren and co-workers and Kulkarni and co-workers have been able to engineer the uniform and large-area formation of random cracks in the film prepared from inorganic or organic colloidal solution, which can be used as template for the physical vapor deposition of transparent and conductive metal mesh.…”

Non-Iridescent Metal Nanomesh with Disordered Nanoapertures Fabricated by Phase Separation Lithography of Polymer Blend as Transparent Conductive Film

“…Au nanomesh with disordered dual-size apertures was fabricated by packing dual-size nanoparticle mixture as a shadow mask for Au deposition. The Au nanomesh film showed excellent angle independent reflection properties as well as good optoelectronic performance [28].…”