Semi-automatic conformal micro-scale printing with the ultra-precise dispensing (UPD) system

Conformal printing enables the integration of functional structures onto arbitrarily shaped surfaces and therefore has seen a drastic increase in research interest. ultra-precise dispensing (UPD) is a promising technology since it allows to print structures down to 1 mu m and thereby pushes the technological limits. However, it typically requires heavy manual intervention for conformal printing, reducing its usefulness and scalablility. In this work, we present a semi-automatic approach for conformal printing with the UPD system in which external measurements and subsequent automatic print path generation replace manual scripting and teaching. We compare the printing time and segmentation of three different projection algorithms, and quantify a tolerance window for the alignment. We then introduce the challenge of nozzle drift in long-duration print jobs, which can reach up to 10 s of mu m. Additionally, we evaluate three printing approaches in terms of line uniformity and show how it can be improved from 40% increased width at segment junctions to only 7% changes. The developed workflow for conformal printing substantially extends the field of application of UPD printing, and makes it an excellent choice for high-precision conformal printing with structure sizes down to 1 mu m.