Interfacial toughening of solution processed Ag nanoparticle thin films by organic residuals

Abstract

Reliable integration of solution processed nanoparticle thin films for next generation low-cost flexible electronics is limited by mechanical damage in the form of delamination and cracking of the films, which has not been investigated quantitatively or systematically. Here, we directly measured the interfacial fracture energy of silver nanoparticle thin films by using double cantilever beam fracture mechanics testing. It was demonstrated that the thermal annealing temperature and period affect the interfacial fracture energy. Also it was found that the interfacial fracture resistance can be maximized with optimized annealing conditions by the formation of organic residual bridges during the annealing process.

Enhancing Adhesion of Screen‐Printed Silver Nanopaste Films

“…The interfacial fracture energy, G c , of screen‐printed Ag nano­paste on the silicon substrate was quantitatively measured using the DCB fracture mechanics testing method …”

“…It also provided more accumulation space for organic residues at the interface. Moreover, the presence of the organic residues at the interface induced plastic deformation in the bonded layer, and bridging of the organic residues during film delamination. When the interface begins to separate, the energy required to debond interface increases due to the energy dissipated by stretching the organic bridges, which are stretched across the opening crack front .…”

“…Previous interfacial adhesion studies on printed metal nanoparticle films using peel, friction, and shear tests were indirect approaches without fundamental mechanisms. Although the adhesion properties using double cantilever beam (DCB) test have been reported, it was limited only to the spin‐coated silver ink for inkjet applications with impractical sintering times of a few hours. Considering the significant technological and industrial importance of screen‐printed metal nanopastes in electronic devices, it is essential to enhance the interfacial adhesion properties and to investigate the fundamental adhesion mechanisms.…”

Anomalous interface adhesion of graphene membranes

“…Supported on a substrate, the interfacial interaction between graphene and its substrate has been one of the key questions from both scientific and technological impetuses34. Up to now, a number of theoretical5678 and experimental9101112 methods have been employed to address the interface adhesion energy between graphene and different types of substrates and further explore the underlying mechanism. Strikingly, the available results with regard to the adhesion energies in graphene membranes show the evident thickness dependence.…”

Highly Conductive and Fatigue‐Free Flexible Copper Film Electrode Fabricated by a Facile Dry Transfer Technique

“…One is the weak adhesion strength of the interface between the metal thin film and flexible polymer substrates caused by the huge isomerism of materials. [24] On the other hand, owing to the poor heat resistance and unstable chemical properties of the polymer substrates, the deposition temperature is confined to a relatively low range, which is adverse to the crystallization of metal particles as well as the electrical performance. [25] The adhesive strength of the metalpolymer substrates can be improved by inserting a buffer interlayer, [26] varying the roughness of the interface, [27] and O 2 plasma treatment.…”