The application of the serpentine mesh layout in stretchable electronics provides a feasible method to achieve the desired stretchability by structural design instead of modifying the intrinsic mechanical properties of the applied materials. However, previous works using the serpentine layout mainly focused on the optimization of structural stretchability. In this paper, the serpentine mesh design concept is used to transform the high-performance but hard-to-stretch piezoelectric film into a stretchable form. The serpentine layout design strategies for the piezoelectric film, which aim at not only desired stretchability but also high utilization of the strain in the piezoelectric film during deformation, are discussed with experimental and computational results. A stretchable micromotion sensor with high sensitivity is realized using the piezoelectric film with a serpentine layout. Human voice recognition applications of the sensor, including speech pattern recognition with machine learning, are demonstrated with the sensor integrated with a wireless module. The stretchable micromotion sensor with a serpentine layout illustrates the broader application of serpentine layout design in the functional materials of stretchable electronics, which can further extend the range of available functional materials for novel stretchable electronic devices.

Research interest in VO2, one of the well‐known transition metal oxides featured by the metal–insulator transition, has resulted in a half‐century's accumulation of fundamentals toward a crystal clear description of the transition mechanism. To understand the interplay between extra electrons and lattice across the transition in VO2‐based integrated electronic devices, a heterostructure of VO2/CH3NH3PbI3 is constructed to investigate the structural evolution when hot electrons are injected from CH3NH3PbI3 to VO2 upon light irradiation. The decrease in the resistance of VO2 confirms the presence of extra electrons injected from CH3NH3PbI3 upon light irradiation. Then, Raman spectra are used to study the structural evolution of VO2 with temperature. The damping in the Raman intensity and the shift in Raman peak of VO2 near transition temperature implicate that the interplay between extra electron injection and lattice weakens the V–V vibration in VO2. This study provides a fundamental framework for understanding the interplay between extra charge and lattice in VO2.