Multilayer dielectric structures are provided having silicon nitride (SiN) and silicon oxynitride (SiNO) films for use as capping layers, liners, spacer barrier layers, and etch stop layers, and other components of semiconductor nano-devices. For example, a semiconductor structure includes a multilayer dielectric structure having multiple layers of dielectric material including one or more SiN layers and one or more SiNO layers. The layers of dielectric material in the multilayer dielectric structure have a thickness in a range of about 0.5 nanometers to about 3 nanometers.