The fabrication and processing of PLLA films employed solvent casting, uniaxial stretching, and thermal annealing to enhance their piezoelectric properties. The detailed methodology is described in our previous work . Briefly, PLLA was dissolved in chloroform and cast onto a flat glass substrate, allowing the solvent to evaporate, resulting in uniform polymer films. These films were then subjected to uniaxial stretching to 100% elongation and were thermally annealed at 80°C. This combination of solvent casting, stretching, and thermal annealing not only ensures the mechanical robustness of PLLA films but also prepares the material for enhanced piezoelectric functionality. By carefully controlling the processing parameters, it is possible to achieve the molecular alignment and crystallinity necessary for high-performance piezoelectric applications. These properties are critical for biomedical devices, where the ability to reliably convert mechanical stimuli into electrical signals underpins their effectiveness.