Asymmetric Metal/α-InSe/Si Crossbar Ferroelectric Semiconductor Junction.

A ferroelectric semiconductor junction is a promising two-terminal ferroelectric device for nonvolatile memory and neuromorphic computing applications. In this work, we propose and report the experimental demonstration of asymmetric metal/α-InSe/Si crossbar ferroelectric semiconductor junctions (c-FSJs). The depletion in doped Si is used to enhance the modulation of the effective Schottky barrier height through the ferroelectric polarization. A high-performance α-InSe c-FSJ is achieved with a high on/off ratio > 10 at room temperature, on/off ratio > 10 at an elevated temperature of 140 °C, retention > 10 s, and endurance > 10 cycles. The on/off ratio of the α-InSe asymmetric FSJs can be further enhanced to >10 by introducing a metal/α-InSe/insulator/metal structure.