The rapid proliferation of flexible, wearable, and transparent electronics has driven a massive demand for high-performance device components. However, the development of such electronics is fundamentally hindered by conventional flexible substrates such as polymers, which suffer from poor thermal tolerance and chemical instability, thereby limiting the integration of high-quality crystalline materials. To overcome these bottlenecks, van der Waals (vdW) heteroepitaxy on muscovite mica—a platform known as “MICAtronics”—has emerged as a revolutionary solution. This plenary talk will explore the fundamental mechanisms and recent breakthroughs of this technology, highlighting three of its most remarkable characteristics.

First, muscovite mica serves as an outstanding flexible substrate with extraordinary environmental stability. When thinned to the micrometer scale, it exhibits excellent mechanical flexibility while retaining high optical transparency, chemical inertness, and extreme thermal stability, capable of withstanding processing temperatures up to 1300 K. These robust properties enable it to withstand harsh fabrication environments that typical polymer substrates cannot withstand.

Second, the vdW heteroepitaxy platform enables the direct epitaxial growth of a wide variety of functional materials. Unlike conventional epitaxy that requires strong chemical bonding and strict lattice matching, vdW epitaxy relies on weak intermolecular forces. This unique growth mechanism significantly relaxes lattice-matching constraints, enabling the epitaxially integrated growth of diverse 3D high-quality functional materials—ranging from transparent conducting oxides and ferroelectrics to semiconductors and magnetic materials—onto the 2D layered mica substrate.

Third, the weak vdW interaction at the film-substrate interface enables effortless mechanical separation. The epitaxial overlayers can be easily peeled off from the mica substrate, mitigating the substrate clamping effect and creating unconstrained, freestanding functional thin films. Crucially, because muscovite cleaves perfectly along its vdW gap without leaving surface dangling bonds, the mechanically separated films exhibit pristine, atomic-level flatness at the interface.

By unifying superior mechanical flexibility, broad material compatibility, and the ability to produce atomically flat freestanding films, van der Waals heteroepitaxy on muscovite provides an unparalleled foundation for soft technology. I look forward to discussing how this platform paves the way for advanced flexible sensors, actuators, and smart electronic systems.