LAUSR

Abstract Efficient manufacturing of composite structure is one of the key challenges in the fabrication of flexible devices. Laser direct writing provides a solution due to its area selectivity, controllability and rapid processing. In this study, one-step patterning of Cu/CuxO structure with tunable composition on flexible substrate has been realized with laser direct writing on Cu precursor film. An integrated humidity sensor that combines a CuxO-rich porous sensing structure with a conductive Cu-rich structure has been fabricated. The one-step-written device showed high sensitivity to human breathing. This work highlights the promise of this one-step mask-less laser writing as an efficient, rapid and low-cost composite structure fabrication process for flexible devices.