Self-Adaptive Dielectrics with Tunable Nonlinear Electrical Conductivity via Virus-Like Structures Composed of Metal Particles

Abstract

Self-adaptive dielectrics (SADs), with the characteristics of rapid charge dissipation in electric field distortion, is regarded as the future material for package insulation of advanced electronic devices. The current landscape of SADs is incapable to achieve tunable nonlinear electrical conductivity and threshold field strength due to the inherent Schottky barrier, significantly limiting the application scenarios of SADs. Here, a strategy is reported to construct a stepped Schottky barrier through virus-like structures, which are composed of subminiature metal particles and semiconductor microspheres. It is found that the metal particles can serve as the capture center to attract the free charge in the matrix, precisely instructing the charge transfer pathway. The barriers between metal particles and semiconductor filler, flexibly controlled by the composition of metal particles, endow with extra source of nonlinear conductivity. Under the optimal composition and size of metal particles, SADs exhibit prominent nonlinear electrical conductivity and reliable adaptive charge release characteristics under pulsed electric field. The work pioneers a breakthrough by overcoming the constraint that SADs are previously limited to the inherent Schottky barrier of semiconductor materials and enabling the unprecedented controllability and flexibility of nonlinear electrical characteristics by metal particles, contributing a distinctive perspective to the development of SADs.