A Ferroelectric Semiconductor Field-Effect Transistor

A ferroelectric semiconductor field-effect transistor (FeS-FET) was proposed and experimentally demonstrated for the first time. In this novel FeS-FET, a 2D ferroelectric semiconductor α-In₂Se₃ is used to replace conventional semiconductor as channel. α-In₂Se₃ is identified due to its proper bandgap, room temperature ferroelectricity, the ability to maintain ferroelectricity down to a few atomic layers and the feasibility for large-area growth. An atomic layer deposited (ALD) Al₂O₃ passivation method was developed to protect and enhance the performance of the α-In₂Se₃ FeS-FETs. The fabricated FeS-FETs exhibit high performance with a large memory window, a high on/off ratio over 10⁸, a maximum on-current of 671 μA/μm, high electron field-effect mobility with μ_FE= 312 cm²/Vs in forward sweep and μ_FE= 488 cm²/Vs in reverse sweep, and the potential to exceed the existing Fe-FETs for non-volatile memory applications.