Fractal dendrite-based electrically conductive composites for laser-scribed flexible circuits

Abstract

Fractal metallic dendrites have been drawing more attentions recently, yet they have rarely been explored in electronic printing or packaging applications because of the great challenges in large-scale synthesis and limited understanding in such applications. Here we demonstrate a controllable synthesis of fractal Ag micro-dendrites at the hundred-gram scale. When used as the fillers for isotropically electrically conductive composites (ECCs), the unique three-dimensional fractal geometrical configuration and low-temperature sintering characteristic render the Ag micro dendrites with an ultra-low electrical percolation threshold of 0.97 vol% (8 wt%). The ultra-low percolation threshold and self-limited fusing ability may address some critical challenges in current interconnect technology for microelectronics. For example, only half of the laser-scribe energy is needed to pattern fine circuit lines printed using the present ECCs, showing great potential for wiring ultrathin circuits for high performance flexible electronics.

An Ultra‐sensitive, Rapidly Responsive Strain Sensor Based on Silver Microflakes by Simple Process

“…The design of new materials including optimization of the design of the conductive fillers and polymer matrix. The former can reduce the tunnel distance between the conductive filler and the latter can help to reduce the tunnel potential under deformation . The addition of conductive polymers to the matrix provides additional carrier channels and significantly reduces contact resistance.…”

Synthesis of polypyrrole nanoparticles and their applications in electrically conductive adhesives for improving conductivity

“…[3][4][5][6] Besides being used as traditional joining materials, ECAs can be easily printed to high conductive circuits. Thus, ECAs composed of polymer matrices and conductive llers have various applications in printing exible circuits, 7,8 wearable and stretchable radio-frequency identication (FRID) devices, 9 capacitive touch panel modules 10 and so on. However, the disadvantage of ECAs is their high electrical resistance, which is usually caused by some lubricant residues (mostly fatty acids) on the surface of conductive llers during the preparation processes by milling.…”

React‐on‐Demand (RoD) Fabrication of Highly Conductive Metal–Polymer Hybrid Structure for Flexible Electronics via One‐Step Direct Writing or Printing

“…Recently, various printing techniques have been demonstrated to fabricate flexible electronics, such as inkjet printing, gravure printing, screen printing, transfer printing, extrusion printing, laser printing, and aerosol jet printing . In addition, based on the newly developed integrated 3D printing system, printed electronics can be fabricated in a 3D manner, exhibiting huge potential for the manufacturing of devices that require arbitrary constructs and unique functions .…”