“…Several oxide NL combinations such as Al 2 O 3 /TiO 2 , Al 2 O 3 /ZnO, ZrO 2 /HfO 2 , ZrO 2 /Gd 2 O 3 , HfO 2 /Ta 2 O 5 , CeO 2 /HfO 2 , HfO 2 /LaAlO 3 , Al 2 O 3 /ZrO 2 , Al 2 O 3 /MgO, , Al 2 O 3 /HfO 2 , , and so forth have been investigated to achieve improved electrical and dielectric properties required for aforementioned applications. Among these, the Al 2 O 3 /TiO 2 /Al 2 O 3 (ATA) NL has emerged as the most preferred candidate for high- k applications, owing to its low cost, excellent thermal stability, and superior electrical and dielectric properties. , Initial studies on ATA NLs with layer thicknesses of the order of a few nanometers have reported k values less than that of TiO 2 ; , however, significantly enhanced k values were achieved when thicknesses of Al 2 O 3 and TiO 2 layers were reduced to the subnanometric regime. − Although dielectric constants of ∼1000 and 850 have been reported for atomic layer deposition (ALD)-grown ATA NLs with sublayer thicknesses ∼0.2 and 0.5 nm, these structures suffered from high dielectric losses of ∼10 and 2, respectively. , Furthermore, the observed high- k values for ATA NLs have been attributed to charge accumulation across the heterogeneous interfaces of insulating (Al 2 O 3 ) and semiconducting (TiO 2 ) sublayers due to the well-known Maxwell–Wagner (M–W) relaxation .…”