AlScN: characteristics, micro/nano fabrication and multiple applications

Abstract Aluminum scandium nitride (AlScN), an emerging Ⅲ-nitride semiconductor material, has attracted significant attention in recent years due to its exceptional piezoelectric properties, high thermal stability, tunable bandgap, and excellent compatibility with micro/nano fabrication. This paper systematically reviews the crystal structure, fundamental properties, and property modulation mechanisms of AlScN. It also summarizes recent progress in micro/nano fabrication technologies, including deposition, etching, and device integration. Furthermore, the applications of AlScN in diverse fields such as micro-electromechanical systems (MEMS), RF communications, energy conversion, optoelectronics and sensors are discussed. Finally, current challenges and promising future research directions for AlScN are outlined.