Characterization of transient currents in HfO2 capacitors in the short timescale

We present a detailed experimental investigation of transient currents in HfO2 capacitors in the short timescale. We show that the transient currents flowing through the capacitor plates when the gate voltage is reset to zero after a low voltage stress period follow a power-law time dependence t−α (with α ≃ 1) over more than eight decades of time and down to the μs timescale. As transient currents in HfO2 are largely increased with respect to the SiO2 case, these results confirm that transient effects can be a severe issue for the successful integration of high-k dielectrics.