Resumen de Development and optimization of inkjet printing based technologies for hybrid printed circuit boards
Francsico Javier Arrese Carrasquer
The main goal of this doctoral thesis is the development and optimization of inkjet-based technologies for hybrid electronic circuits manufacturing, as well contribute on the development of the incoming low cost electronics. Regarding that, a novel solution for connecting regular SMDs and standard silicon SMD packages by inkjet printing is proposed. The novel connecting method allows the assembling at very low temperatures, and thus assures the compatibility with the incoming substrates. Electrical contact resistance and shear strength measurements performed by silver nanoparticle-based ink are comparable to benchmark connecting materials. In sum up, flexible hybrid circuit is successfully manufactured by silver nanoparticle-based ink on paper, where different SMDs size-shaped are assembled demonstrating the reliability and feasibility of the proposed method.
Another objective of the work is to apply and adapt the print-on-slope technique to assemble directly the silicon dies on PCB, proposing a novel strategy to overcome the drawbacks of the wire bonding in the Conductive AFM measurements. Then, a novel setup for conductive AFM mode 2D materials characterization was manufactured. The 2D connection on ramp-shape terminations gives a better functionality than current wire bonding connections. The AFM tip moves over the silicon die without physical obstruction, giving a unique solution at this novel method to characterize the material degradation.
In the field of multilayer hybrid PCB manufacturing, the goal is to prove the potentiality of different metal-insulator-metal structures inkjet-printed and evaluate their reliability and the electrical performance for low cost multilayer circuit based on paper substrate. In the light of the results, heterogeneous structures combining inorganic and organic dielectric material, where PVP fills the inorganic cracks and voids, possess a similar and outstanding feasibility in both paper and glass substrate without short-circuits.
The greatest achievement of this work is the development and optimization of a novel capillarity-assisted SMD assembling method for the manufacturing of hybrid circuits inkjet-printed. In addition, taking advantage of print-on-slope technique, direct assembling of silicon die integrated circuits to PCB is successfully applied. Moreover, heterogeneous structures inkjet-printed open new solutions for multilayer hybrid circuits.
