Tailoring dielectric relaxation in ultra-thin high-dielectric constant nanolaminates for nanoelectronics

The work reported here demonstrates the feasibility of controlling the dielectric properties-high dielectric constant (k) and substantially extended relaxation frequency-of thin film nanolaminates (NLs) consisting of alternating TiOx and Al2O3 sublayers with various sublayer thicknesses grown by atomic layer deposition. For 150 nm thick TiOx/Al2O3 NLs with sub-nanometer thick sublayers, few Angstrom change in sublayer thickness dramatically increases relaxation cut-off frequency by more than 3 orders of magnitude with high dielectric constant (k > 800). This unusual phenomenon is discussed in the framework of two-phase Maxwell-Wagner relaxation. (C) 2013 American Institute of Physics.