EGaIn‐Assisted Room‐Temperature Sintering of Silver Nanoparticles for Stretchable, Inkjet‐Printed, Thin‐Film Electronics. Issue 29 (29th May 2018)

• Record Type: Journal Article
• Authors: Tavakoli, Mahmoud; Malakooti, Mohammad H.; Paisana, Hugo; Ohm, Yunsik; Green Marques, Daniel; Alhais Lopes, Pedro; Piedade, Ana P.; de Almeida, Anibal T.; Majidi, Carmel
• Is Part Of: Advanced materials. Volume 30:Issue 29(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-05-29
• Subjects: conductive ink -- epidermal electronics -- hydrographic transfer -- printed electronics -- stretchable electronics; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201801852
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Coating inkjet‐printed traces of silver nanoparticle (AgNP) ink with a thin layer of eutectic gallium indium (EGaIn) increases the electrical conductivity by six‐orders of magnitude and significantly improves tolerance to tensile strain. This enhancement is achieved through a room‐temperature "sintering" process in which the liquid‐phase EGaIn alloy binds the AgNP particles (≈100 nm diameter) to form a continuous conductive trace. Ultrathin and hydrographically transferrable electronics are produced by printing traces with a composition of AgNP‐Ga‐In on a 5 µm‐thick temporary tattoo paper. The printed circuit is flexible enough to remain functional when deformed and can support strains above 80% with modest electromechanical coupling (gauge factor ≈1). These mechanically robust thin‐film circuits are well suited for transfer to highly curved and nondevelopable 3D surfaces as well as skin and other soft deformable substrates. In contrast to other stretchable tattoo‐like electronics, the low‐cost processing steps introduced here eliminate the need for cleanroom fabrication and instead requires only a commercial desktop printer. Most significantly, it enables functionalities like "electronic tattoos" and 3D hydrographic transfer that have not been previously reported with EGaIn or EGaIn‐based biphasic electronics. Abstract : Stretchable thin‐film electronics that can be transferred to 3D surfaces or human skin are created by a versatile, fast, and cost‐effective processing method. The circuits are composed of inkjet‐printed traces of silver nanoparticles (AgNPs) that are coated with a eutectic gallium indium (EGaIn) liquid alloy. The EGaIn coating dramatically reduces the resistivity of the AgNP traces and enables stretchable functionality.