Study of Transient Current Dependent on Different Traps in HfZrO FeFET with Thin HfO 2 Insertion

The trapping/de-trapping behaviors are investigated in HfO 2 -based ferroelectric field-effect transistor (FeFET) with 2 Å HfO 2 insertion layer at the Hf 0.5 Zr 0.5 O 2 /SiO 2 interface. The transient current related to the trapping/de-trapping process of carriers is measured and corresponding time constant spectrum is extracted, revealing three distinct traps: DP 1 ( τ = 0.2 s), DP 2 ( τ = 1 s), and DP 3 ( τ = 6 s). The activation energies of different traps are compared and analyzed for samples with and without HfO 2 insertion. The activation energies of DP 2 and DP 3 slightly increase after a 2 Å HfO 2 layer insertion. In accordance with the dependence of transient current and time constant spectrum on the gate and drain filling voltage, two types of traps are identified: DP 1 is at the Si/SiO 2 interface and DP 2 and DP 3 are within the HfZrO film.