Inkjet printing metals on flexible materials for plastic and paper electronics

Inorganic printed electronics is now recognized as an area of tremendous commercial, potential and technical progress. Many research groups are actively involved worldwide in developing metal nanoparticle inks and precursors for printing inorganic/organic materials using different printing techniques. This review article focuses on inkjet printed metal structures and their applications. It comprises ink formulation, optimal droplet formation as well as adhesion of the printed patterns at the underlying substrate and post-treatment like sintering to be considered in the initial ink design. Besides some examples demonstrating aspects on ink formulation via patterning solid surfaces such as glass and silicon oxide, special emphasis will be placed on compatibility for usage in plastic and paper electronics. Printing of nanoparticles of copper, silver, gold etc. will be discussed and will be compared to printing of a variety of metal-organic precursor inks. Finally, a brief account on exemplary applications using the printed inorganic nanoparticles/materials is provided.