Bi₂Te₃-Based Thermoelectric Films Fabricated by Magnetron Sputtering

Bi₂Te₃-based materials are benchmark room-temperature thermoelectrics, widely used in refrigeration, waste heat recovery, and microdevice thermal management. Magnetron sputtering demonstrates significant potential as an effective strategy for the mass production of superior Bi₂Te₃ thin films, offering advantages such as dense microstructure, controllable composition, good repeatability, and compatibility with semiconductor processes. However, existing studies largely focus on individual factors affecting film properties, lacking a systematic understanding of the interrelationships among process parameters, microstructures, and thermoelectric performance. Poor comparability across studies due to varying deposition conditions further limits insight into key controlling mechanisms. Recent efforts have centered on three regulatory aspects in magnetron sputtering: (1) optimization of sputtering parameters (e.g., power, pressure, temperature, and target composition); (2) post-annealing treatment; and (3) doping modification. Notable progress has been made in enhancing thermoelectric performance through these approaches. This paper provides a comprehensive overview of recent advancements in the fabrication of Bi₂Te₃ thin films via magnetron sputtering, focusing on how process parameters, post-treatment, and doping affect microstructure, stoichiometry, and thermoelectric properties. The aim is to elucidate structure-performance correlations and guide the optimized preparation of high-performance films.