Transparent Conductive Printable Meshes Based on Percolation Patterns

Abstract

Transparent conductive meshes were fabricated by inkjet printing on flexible substrate using a percolation pattern created by random removal of conducting bonds from a regular square two-dimensional lattice. With this approach, a higher gain in optical transmittance than electrical conductivity loss is achieved above the percolation threshold. As a result of this, a figure of merit for the percolation pattern is improved with respect to a regular square mesh. The transmittance (T), sheet resistance (R), and figure of merit (F) on percentage of removed bonds for square lattices were measured. The gain of the figure of merit was observed in the range of removed bonds from 5% to 15%. Our best samples exhibit T = 84%, R = 1.3 Ω/sq, and F = 130 × 10–3 Ω–1 (highest F value and lowest R value) and T = 93%, R = 8 Ω/sq, and F = 65 × 10–3 Ω–1 (highest T value). This demonstrates an excellent transparent conductive film (TCF) performance and is significantly better than any continuous TCF. The percolation meshes demonstrate good mechanical stability and the absence of a Moiré effect. A distinctive feature of this method is its universality and capability of being adapted to any symmetrical or asymmetrical pattern and deposition technique.

Multipass Inkjet Printing of Lead Halide Perovskite Pixels onto Flexible Substrates

“…Such foils are flexible to bending but withstand distortion under stress. We studied pristine PET foil as delivered (Melinex ST505, 125 μm thick) with different amounts of oxygen plasma cleaning as well as PET foils spin-coated with PS, PMMA, and PEDOT:PSS in our lab to vary the surface energy of ink and substrate. , Finally, we tested a commercial foil with a 20 μm-thick layer of mesoporous silica (JS-220 Novele from NovaCentrix), which had shown superb printing behavior in an earlier study …”

“…26,27 Finally, we tested a commercial foil with a 20 μm-thick layer of mesoporous silica (JS-220 Novele from NovaCentrix), which had shown superb printing behavior in an earlier study. 2 We found that PET foils were somewhat curled as obtained, which caused problems for spin coating. Hence, we preheated the PET foils carefully before coating them to remove residual strain, with the exception of silica-coated PET foil, which was already flat.…”

“…Emerging from the flexible electronics family is the challenging technology of flexible displays, borne from the shortcomings of rigid glass-based substrates that cannot be rolled up or folded and are subject to shattering. In such displays, polymer substrates are most commonly used due to their flexibility, transmissivity, low surface roughness, etc. , Herein, we study the deposition of high-performance methylammonium lead iodide (MAPbI 3 ) perovskite light emitters on flexible polyethylene terephthalate (PET) substrates modified with various surface coatings.…”

“…In such displays, polymer substrates are most commonly used due to their flexibility, transmissivity, low surface roughness, etc. 1,2 Herein, we study the deposition of high-performance methylammonium lead iodide (MAPbI 3 ) perovskite light emitters on flexible polyethylene terephthalate (PET) substrates modified with various surface coatings.…”