Atomic layer chemical vapor deposition of ZrO2-based dielectric films: Nanostructure and nanochemistry

A 4 nm layer of ZrOx (targeted x∼2) was deposited on an interfacial layer (IL) of native oxide (SiO, t∼1.2 nm) surface on 200 mm Si wafers by a manufacturable atomic layer chemical vapor deposition technique at 300 °C. Some as-deposited layers were subjected to a postdeposition, rapid thermal annealing at 700 °C for 5 min in flowing oxygen at atmospheric pressure. The experimental x-ray diffraction, x-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and high-resolution parallel electron energy loss spectroscopy results showed that a multiphase and heterogeneous structure evolved, which we call the Zr–O/IL/Si stack. The as-deposited Zr-O layer was amorphous ZrO2-rich Zr silicate containing about 15% by volume of embedded ZrO2 nanocrystals, which transformed to a glass nanoceramic (with over 90% by volume of predominantly tetragonal-ZrO2 (t-ZrO2) and monoclinic-ZrO2 (m−ZrO2) nanocrystals) upon annealing. The formation of disordered amorphous regions within some of the nanocr...