The use of atomic layer deposition (ALD) to form a nanolaminate dielectric of zirconium oxide (ZrO2), hafnium oxide (HfO2) and tin oxide (SnO2) acting as a single dielectric layer with a formula of Zrx Hfy Sn1-x-y O2, and a method of fabricating such a dielectric layer is described that produces a reliable structure with a high dielectric constant (high k). The dielectric structure is formed by depositing zirconium oxide by atomic layer deposition onto a substrate surface using precursor chemicals, followed by depositing hafnium oxide onto the substrate using precursor chemicals, followed by depositing tin oxide onto the substrate using precursor chemicals, and repeating to form the thin laminate structure. Such a dielectric may be used as a gate insulator, a capacitor dielectric, or as a tunnel insulator in non-volatile memories, because the high dielectric constant (high k) provides the functionality of a much thinner silicon dioxide film.