Automatic Transformation of Membrane-Type Electronic Devices into Complex 3D Structures via Extrusion Shear Printing and Thermal Relaxation of Acrylonitrile-Butadiene-Styrene Frameworks

This work demonstrates a means of automatic transformation from planar electronic devices to desirable 3D forms. The method uses a spatially designed thermoplastic framework created via extrusion shear printing of acrylonitrile-butadiene-styrene (ABS) on a stress-free ABS film, which can be laminated to a membrane-type electronic device layer. Thermal annealing above the glass transition temperature allows stress relaxation in the printed polymer chains, resulting in an overall shape transformation of the framework. In addition, the significant reduction in the Young's modulus and the ability of the polymer chains to reflow in the rubbery state release the stress concentration in the electronic device layer, which can be positioned outside the neutral mechanical plane. Electrical analyses and mechanical simulations of a membrane-type Au electrode and indium gallium zinc oxide transistor arrays before and after transformation confirm the versatility of this method for developing 3D electronic devices based on planar forms.