Impact of the polarization on time-dependent dielectric breakdown in ferroelectric Hf_0.5Zr_0.5O₂ on Ge substrates

In this work, polarization-dependent time-dependent dielectric breakdown in ferroelectric HZO Ge MOSCAPs is presented. First, ferroelectric HZO Ge MOSCAPs with and without in-situ NH₃ plasma interfacial layer treatment exhibit the two distinct remnant polarization (P_r). Secondly, the device with a larger P_r shows a higher gate leakage current and smaller time-to-breakdown (t_BD) compared to the device with a smaller P_r. Then, a physical model based on the high probability of the electron tunneling accelerating the formation of the percolation path is proposed. Finally, the device with large P_r shows a lower extrapolated operating voltage. However, more than 1.5 V of the extracted operation voltage for 1% failure of 10 year lifetime in the device with large P_r still can be obtained.