Optimization of Piezo-Driven Jet Valve Dispensing Process for the Geometrical Control of Printed Sensors Based on Silver and MXene Inks

Printed sensors offer unique benefits—highly customizable designs, low-cost prototyping, and a wide range of materials and properties—which can be exploited. Piezo-driven jet valve dispensing is a printing technique suitable for the fabrication of sensors and electronics directly on the surfaces (both 2-D and 3-D) of smart objects and devices but needs additional analysis and study. In this work, we studied the influence of printing parameters on the performance of the Nordson PICO Jetting system mounted on the Neotech PJ15X machine by depositing a silver ink, typically used for the fabrication of sensors and interconnections, and a Ti3C2TX ink, a very promising 2-D material in the sensing and electronics fields for its extraordinary physical, electrical, chemical, and mechanical properties. A tuning approach was proposed to tune the printing parameters correctly. The profiles of the cross sections of printed lines were evaluated, including the process variability, when the values of the printing parameters were changed. In the case of Ti3C2TX, the improper setting of the printing setup caused undesired spots and irregular lines. The optimal settings for the printing setup were found for each ink, reaching a variability in the profile of 1.5%.