Stretchable Structural Color Filters Based on a Metal–Insulator–Metal Structure

Abstract

make structural-based color filters a promising choice for potential future opticsbased applications.In the area of flexible electronics, a number of flexible color filters have recently been reported utilizing either thin-film layer stacks or nanostructures. [15][16][17][18] These flexible filters are generally fabricated on plastic substrates such as polyethylene terephthalate (PET) that are hundreds of micrometers in thickness, feature millimeter to centimeterscale bending radii, and demonstrate little change in transmittance after repeated mechanical bending. Flexible filters can be suitable for a wide range of potential uses where an unusual form factor is required, or even integration with wearable devices. As an example, there have been previous reports of sensors either reliant on optical phenomena or containing simple optical elements that are demonstrably flexible enough to adhere to human skin. [19][20][21] Such devices would require any integrated components to have similar or better mechanical properties in excess of those possessed by current flexible color filters. One important factor to consider is conformal adhesion to a complex surface. Decreasing the film thickness generally results in decreased bending stiffness, allowing for greater adhesion to the surface. [22][23][24][25] To accomplish this, the thickness of the substrate layer can be decreased. Indeed, increased conformity while preserving filter effectiveness would be highly conducive for applications like on-skin pulse oximeters or wearable/implantable imagers where such characteristics are necessary. [26][27][28] Based on these requirements, in addition to flexibility an ideal color filter would also need to simultaneously be ultrathin and stretchable for sufficient mechanical compatibility.Herein, we demonstrate ultrathin, stretchable, and flexible structural color filters based on a simple metal-insulator-metal (MIM) structure on a 1.3 µm ultrathin substrate. We first fabricate silver-silicon dioxide-silver (Ag-SiO 2 -Ag) structures on top of ultrathin parylene substrates and characterize their basic optical and mechanical characteristics. We next investigate how effective the color filters are at both passing the desired wavelengths of light and blocking the undesired wavelengths of light both before and after mechanical deformation. We also describe the angular sensitivity of the color filters and assess its overall impact on filter performance. Remarkably, we find Color filters play a big role in a large number of modern technologies such as displays, sensors, and photovoltaics. In particular, structural color filters possess a number of advantages like high tolerance to heat, resistance to photodegradation, and long-term stability that make them a promising choice for potential future optics-based applications. In the field of flexible electronics, there are many sensors either reliant on optical phenomena or containing simple optical elements that are demonstrably flexible enough to adhere to uneven, deformable surfaces. Such de...

Generation of Reflection Colors from Metal–Insulator–Metal Cavity Structure Enabled by Thickness-Dependent Refractive Indices of Metal Thin Film

“…Meanwhile, planar and multilayered structures provide an alternative opportunity in controlling and manipulating light–matter interactions. A metal–insulator–metal (MIM) cavity structure formed by thin continuous layers is of special interest because its fabrication is lithography free and involves only thin-film deposition. − The MIM structure is a Fabry–Perot (FP) cavity that enhances resonant absorption within the structure. Due to their advantages and promising applications, FP-cavity-based spectral filters have been extensively studied.…”

Perylene Diimide Incorporated Polyurethane Polymer as Potential Colour Filter Material with Non‐fluorescent Property†

“…Chemicals and synthesis 1,6,7,4,9, dianhydride (PTCDA, 98%, Beijing HWRK company), 6-amino-1-hexanol (98%, Energy Chemical), 2-octyldodecan-1-amine (95%, Beijing HWRK company), isocyanate-terminated polyethers (PET, a hydroxyterminated random copolymer of ethylene oxide and tetrahydrofuran, Meryer), methylene diphenyl diisocyanate (MDI, 98%, Meryer), hydrogenated MDI (HMDI, 90%, Aladdin), 1,4-butanedio (BDO, 99%, Heowns) were used as received. All the other solvents were purchased from Jiangtian Chemical Reagents Co., Ltd. and used without further purification unless otherwise specified.…”

“…The mechanical properties and heat resistance are important for the evaluation of the filters. [ 9‐12 ] In flexible display equipment, the filter needs to have more excellent tensile properties. What's more, the filter needs to undergo heat treatment in the preparation process, and the good thermal stability of the dye helps to avoid the formation of defects.…”

Large‐Scale, Panchromatic Structural Color Manipulation via Thermal Trimming

“…Over the last decade, structural color based on photonic structures has attracted extensive attention due to high resolution, [ 1,2 ] strong stability, [ 3–5 ] and easy production of compact monolithically integrated devices, [ 6,7 ] These attributes have rendered structural colors of great interest to printing, [ 1,2 ] display, [ 8,9 ] imaging, [ 10,11 ] decoration, [ 12,13 ] colorimetric sensing, [ 14–17 ] and more importantly, anti‐counterfeiting, [ 9 ] and encryption, [ 18–20 ] Many methods have produced vivid structural colors such as multilayer interference, [ 21–25 ] photonic crystals, [ 26 ] guided mode resonances, [ 27 ] plasmonic resonances, [ 12,28,29 ] and Mie scattering. [ 6,30 ] Especially, thin‐film‐based structural colors such as metal‐insulator‐me`tal (MIM) cavities, [ 8 ] lossy film cavities, [ 23 ] and multilayer [ 21 ] film systems have been implemented for the simplest fabrication and integration on a large scale.…”