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Biodegradable metals as electrodes, interconnectors, and device conductors are essential components in the emergence of transient electronics, either for passive implants or active electronic devices, especially in the fields of biomedical electronics. Magnesium and its alloys are strong candidates for biodegradable and implantable conducting materials because of their high conductivity and biocompatibility, in addition to their well-understood dissolution behavior. One critical drawback of Mg and its alloys is their considerably high dissolution rates originating from their low anodic potential, which disturbs the compatibility to biomedical applications. Herein, we introduce a single-phase thin film of a Mg–Zn binary alloy formed by sputtering, which enhances the corrosion resistance of the device electrode, and verify its applicability in biodegradable electronics. The formation of a homogeneous solid solution of single-phase Mg–3Zn was confirmed through X-ray diffraction and transmission electron microscopy. In addition, the dissolution behavior and chemistry was also investigated in various biological fluids by considering the effect of different ion species. Micro-tensile tests showed that the Mg–3Zn alloy electrode exhibited an enhanced yield strain and elongation in relation to a pure Mg electrode. Cell viability test revealed the high biocompatibility rate of the Mg–3Zn binary alloy thin film. Finally, the fabrication of a wireless heater demonstrated the integrability of biodegradable electrodes and highlighted the ability to prolong the lifecycle of thermotherapy-relevant electronics by enhancing the dissolution resistance of the Mg alloy.

Abstract Multi‐dimensional electronic devices for sensing applications have received immense attention in the fields of bio‐interface electronics and soft robotics to achieve structural manifolds in recent years. The structural diversities of sensors are tuned based on the environments in which they encounter multipurpose and complex form factors of electronics. 3D electronics are one of the emerging sensor platforms characterized by structural adaptability and compatibility on free target surfaces, resulting in unprecedented improvement of spatial resolution. Herein, the recent progress made in the fabrication and usage of 3D electronic sensors that are classified into two groups based on the methodological concepts used for fabrication in bio‐interfaced electronics and soft robotics applications, is reviewed. The latest advances in the design and development of 3D printable and 2D to 3D shape‐deformable electronic sensors are reviewed with a focus on printable materials and deformation mechanisms, respectively. 3D printing techniques enable the facile fabrication of arbitrary and seamless electronics without the use of conventional microfabrication technologies. Deformable electronics cover their self‐tune architectures and functions depending on mechanical deformation based on buckling, origami, and kirigami fabrication strategies. Finally, the printed and deformable 3D sensors show their potential for use in next‐generation sensing platforms.