Picosecond UV laser induced scribing of polyethylene terephthalate (PET) films for the enhancement of their flexibility

• Local flexibility of PET films can be controlled by the laser scribing.
• The scribing depth of PET films can be adjusted by the Power of UV laser.
• Mechanical damages are controlled by the number and depth of scribing lines.

Flexible devices has received a great attention due to their high portability, lightness, and ease of shape reconfiguration. To achieve high flexibility, controlling the mechanical properties of the substrate materials is of importance. In this paper, we controlled the local flexibility of PET films via UV laser scribing. The bending test of the films revealed that their bending curvatures, the associated mechanical damages, and the required bending forces could be successfully tuned by controlling the number and the depth of the scribed lines. Our simple strategy of using laser scribing will find its usefulness in flexible device applications where high flexibility and mechanical stability are required.