Ductile inorganic semiconductors for deformable electronics

Abstract

Traditionally, it is relatively easy to process metal materials and polymers (plastics), while ceramic and inorganic semiconductor materials are hard to process, due to their intrinsic brittleness caused by directional covalent bonds or the strong electrostatic interactions among ionic species. The brittleness of semiconductor materials, which may degrade their functional performance and cause catastrophic failures, has excluded them from many application scenarios. The exploration on room-temperature ductile semiconductors has been a long pursuit of mankind for fabricating deformable and more robust electronics. Guided by this goal, researchers have already found that the plasticity of brittle semiconductors can be enhanced by size effects, which include fewer pre-existing micro-cracks and increased dislocation activity, charge characteristics, and defect density. It has also been explored that a few quasi-layered/van der Waals semiconductors can have exceptional room-temperature metal-like plasticity, enabled by the relatively weak interlayer bonding and easy interlayer gliding. More recently, intrinsic exceptional plasticity has been found in a group of all-inorganic perovskites (CsPbX₃, X = Cl, Br and I), which can be morphed into distinct morphologies through multislip at room temperature, without affecting their functional properties and bandgap energy. Based on the above research status, in this review, we will discuss and present the relevant works on the plasticity found in inorganic semiconductors and the proposed deformation mechanisms. The potential applications and bottlenecks of plastic semiconductors in manufacturing next-generation deformable electronic/optoelectronic devices and energy systems will also be discussed.