Articolo in rivista, 2022, ENG, 10.3390/mi13010057

Assessing the relationships between interdigital geometry quality and inkjet printing parameters

Federico Bertolucci, Nicolò Berdozzi, Lara Rebaioli, Trunal Patil, Rocco Vertechy, Irene Fassi

University of Bologna, Industrial Engineering Department, Bologna, Italy; University of Bologna, Industrial Engineering Department, Bologna, Italy; Consiglio Nazionale delle Ricerche, Institute of Intelligent Industrial Technologies and Systems for Advanced Manufacturing, Milan, Italy; Consiglio Nazionale delle Ricerche, Institute of Intelligent Industrial Technologies and Systems for Advanced Manufacturing, Milan, Italy; University of Bologna, Industrial Engineering Department, Bologna, Italy; Consiglio Nazionale delle Ricerche, Institute of Intelligent Industrial Technologies and Systems for Advanced Manufacturing, Milan, Italy

Drop on demand (DoD) inkjet printing is a high precision, non-contact, and maskless additive manufacturing technique employed in producing high-precision micrometer-scaled geometries allowing free design manufacturing for flexible devices and printed electronics. A lot of studies exist regarding the ink droplet delivery from the nozzle to the substrate and the jet fluid dynamics, but the literature lacks systematic approaches dealing with the relationship between process parameters and geometrical outcome. This study investigates the influence of the main printing parameters (namely, the spacing between subsequent drops deposited on the substrate, the printing speed, and the nozzle temperature) on the accuracy of a representative geometry consisting of two interdigitated comb-shape electrodes. The study objective was achieved thanks to a proper experimental campaign developed according to Design of Experiments (DoE) methodology. The printing process performance was evaluated by suitable geometrical quantities extracted from the acquired images of the printed samples using a MATLAB algorithm. A drop spacing of 140 µm and 170 µm on the two main directions of the printing plane, with a nozzle temperature of 35 °C, resulted as the most appropriate parameter combination for printing the target geometry. No significant influence of the printing speed on the process outcomes was found, thus choosing the highest speed value within the investigated range can increase productivity.

Micromachines (Basel) 13 (1), pp. 57–?

Keywords

Additive manufacturing, inkjet printing, interdigitated electrodes, image processing, Design of Experiments

CNR authors

Patil Trunal Kashinath, Fassi Irene, Rebaioli Lara

CNR institutes

STIIMA – Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato