摘要
Devices in the form of TiN/ferroelectric-HfZrO x (FE-HZO)/polycrystalline or epitaxial GeSn are used to investigate how the crystallinity of GeSn film affects the behaviors and reliability performance. FE-HZO on epitaxial GeSn film reveals higher ferroelectricity as evidenced by a larger remanent polarization (P r ) by 21% as compared with that formed on polycrystalline GeSn film. Devices with epitaxial GeSn film also demonstrate higher dipole switching speed, more robust endurance up to 10 6 cycles (±3.3 MV cm −1 , long pulse width of 1 ms) and better retained polarization up to 10 4 s. The essential factor that determines the more desirable ferroelectric behaviors and reliability lies in the higher quality of the interfacial layer between HZO and GeSn film which helps suppress defect generation and charge trapping. The research results also highlight the importance to improve the interfacial layer quality for enhanced performance of ferroelectric devices formed on polycrystalline semiconductor.