Special phenomena in multilayer deposition of functional particle inks

Abstract

The inkjet deposition of silver particles has been subject to many studies during the last years often taking in account the minimization of the line width and the realisation of conductive structures on temperature sensitive substrates. Beside fine lines on temperature sensitive substrates, inkjet printing of block shaped elements with a layer thickness of several microns on temperature resistant ceramics is of interest in printed electronics. In order to derive the required layer thickness several layers have to be printed on top of each other. As a consequence phenomena like particle flow, structured, uneven surfaces, loss of sharp edges and even pinholes and cracks occur. The study discusses theoretical aspects of ink substrate interaction and highlights the influence of the organic composition of the ink on the appearance of the printed multilayer structures as well as the effect of different ceramic substrates on the printing result. Several characteristic phenomena related to the multilayer deposition of particle inks are identified and solutions concerning ink formulation, choice of the substrate, and processing of the ink are presented.