Polarization‐Enabled Piezoelectric Tellurium–Selenium (Te _x Se _{1– x} ) Thin Films for Memory Switching and Artificial Synaptic Functions

ABSTRACT Two‐dimensional materials with piezoelectricity and polarization‐enabled electromechanical responses provide a promising basis for multifunctional electronics, including memory devices and neuromorphic computing. In this work, we explore cryogenic physical vapor deposition (cryogenic PVD)–grown Te _x Se _1‐x thin films, a tellurium‐based compound with a tunable bandgap and enhanced non‐centrosymmetry, and examine their polarization‐associated electromechanical characteristics. A 10 nm Te _0.9 Se _0.1 film exhibits a clear switchable electromechanical response with a piezoelectric coefficient d ₃₃ of 33 pm/V, together with stable piezoresponse under ambient conditions. Introducing a Se ratio of 0.1 is found to enhance the polarization behavior and domain response while maintaining the crystalline quality of the Te _x Se _1‐x films. Memory devices based on Te _0.9 Se _0.1 show retention beyond 2000 s and remain switchable up to 1000 cycles, with an HRS/LRS ratio exceeding 10 ² under ± 20 V program/erase pulses when read at a drain voltage of 1 V. In addition, synaptic behavior is demonstrated with 92% image recognition accuracy at low energy consumption, suggesting potential for neuromorphic applications. These results highlight the potential of Te _x Se _1‐x films as a polarization‐enabled piezoelectric semiconductor system for future low‐power memory and computing applications.