Transparent Electromagnetic Shielding Film Utilizing Imprinting-Based Micro Patterning Technology

Abstract

Utilization of methods involving component integration has accelerated, owing to the growth of the smart mobile industry. However, this integration leads to interference issues between the components, thereby elucidating the importance of the electromagnetic interference (EMI) shielding technology to solve such issues. EMI shielding technology has been previously implemented via the reflection or absorption of electromagnetic waves by using conductive materials. Nevertheless, to tackle the recent changes in the industry, a transparent and flexible EMI shielding technology is necessitated. In this study, a transparent and flexible EMI shielding material was fabricated by filling a conductive binder in a film comprising an intaglio pattern; this was achieved by using the ultraviolet (UV) imprinting technology to realize mass production. Subsequently, changes in the aperture ratio and shielding characteristics were analyzed according to the structure of the pattern. Based on this analysis, a square pattern was designed and a film with an intaglio pattern was developed through a UV imprinting process. Furthermore, it was confirmed that the transmittance, conductivity, and EMI shielding rate of the film were altered while changing the coating thickness of the conductive particles in the intaglio pattern. The final film prepared in this study exhibited characteristics that satisfied the required EMI shielding performance for electric and electronic applications, while achieving flexible structural stability and transparency.

Providing a Specified Level of Electromagnetic Shielding with Nickel Thin Films Formed by DC Magnetron Sputtering

“…The measurement results show a gradual approach of the values of S21 coefficient with the increase of the film thickness, to the results obtained for the metal sheet. The form of the obtained frequency dependencies is typical for continuous metal films and correlates with the literature data [39]. The main reason for the decrease in S21 coefficient with increasing frequency is an increase in the l/δ ratio, which clearly manifests itself for diamagnetic materials, for example, gold [40].…”

Nanopatterned Polymer Molds Using Anodized Aluminum Templates for Anti-Reflective Coatings

“…This method was performed with the second anodization under the same conditions as the first for 15 s. The morphology characterization of the AAO templates was conducted by FE-SEM. This soft molding technique combined with UV imprinting process exhibited an efficient fabrication of flexible nanostructures [ 31 ]. The method not only produces patterns with the advantage of continuous production over areas as large as several centimeters but is also a particularly high-speed manufacturing process.…”

High-Adhesion Ag Film with Enhanced Electromagnetic Shielding Performance via Post-Treatment of a Polydopamine Adhesive Layer

“…The arrival of 5G communication technology and the development of new electronic equipment that are light weight, thin, and flexible have led to the demand for electromagnetic interference shielding materials. − Due to the excellent conductivity, the metal coating on flexible polymer substrates not only has high electromagnetic shielding performance but also has the required characteristics of flexibility, thinness, and conformal shielding. − During applications, high adhesion also needs to be considered. Nowadays, the electroless deposition method is widely adopted to metalize polymer surfaces.…”