Fabrication of Foldable Metal Interconnections by Hybridizing with Amorphous Carbon Ultrathin Anisotropic Conductive Film

Abstract

With the advent of foldable electronics, it is necessary to develop a technology ensuring foldability when the circuit lines are placed on the topmost substrate rather than in the neutral plane used in the present industry. Considering the potential technological impacts, conversion of the conventional printed circuit boards to foldable ones is most desirable to achieve the topmost circuitry. This study realizes this unconventional conversion concept by coating an ultrathin anisotropic conductive film (UACF) on a printed metal circuit board. This study presents rapid large-area synthesis of hydrogenated amorphous carbon (a-C:H) thin films and their use as the UACF. Since the synthesized a-C:H thin film has electrical transparency, the metal/a-C:H hybrid board reflects the complexity of the underlying metal circuit board. The a-C:H thin film electrically connects the cracked area of the metal line; thus, the hybrid circuit board is foldable without resistance change during repeated folding cycles. The metal/UACF hybrid circuit board can be applied to the fabrication of various foldable electronic devices.

Interface Design for Stretchable Electronic Devices

“…It is based on the multilayer interface between metal thin film and the ultrathin anisotropic conductive film (UACF). [169,170] Pal et al reported an easy method to produce the UACF which is an ultrathin hydrogenated amorphous carbon film (Figure 15a). [169] The UACF had conductance limitation in the lateral direction up to 1.6 µm, but it had no tunneling barrier in the thickness direction.…”

“…[169,170] Pal et al reported an easy method to produce the UACF which is an ultrathin hydrogenated amorphous carbon film (Figure 15a). [169] The UACF had conductance limitation in the lateral direction up to 1.6 µm, but it had no tunneling barrier in the thickness direction. When the UACF was transferred on a complicated metal circuit, the UACF/metal hybrid circuit could reflect the high-resolution complexity and the high conductivity of the underlying metal circuit lines.…”

“…It is based on the multilayer interface between metal thin film and the ultrathin anisotropic conductive film (UACF). [ 169,170 ] Pal et al. reported an easy method to produce the UACF which is an ultrathin hydrogenated amorphous carbon film ( Figure a).…”

“…Reproduced with permission. [ 169 ] Copyright 2019, American Chemical Society. d) Scheme describing the connection of the cracked region by the UACF cover layer in the UACF/UACF/Au electrode.…”

2D Dual Anisotropic Conductive Janus Nanostrips Array Pellicle and Derivative 3D Janus‐structural Pipe Concurrently Endowed with Magnetism and Red‐green Two‐colored Fluorescence

“…With the continuous demand for integrated and portable nanodevices, functional materials with single-performance and large-size are gradually unable to meet the developing requirements of devices, and thus the realization of multiple properties in one material has been widely concerned by researchers, and the material with multiple properties has wide applications in many fields [1][2][3][4] Anisotropic materials can obtain different functions in different direction , [5,6] Anisotropic conductive film (ACF) has been used in many fields on account of their copacetic mechanical capacity, high electrical conductivity [7][8][9] and environmental pollution-free, [10] such as, storage battery [11,12] wearable pressure sensors, [13] filtration separation, [14] transparency electrode materials, [15] etc. ACF is classified into different types.…”