Titanium-based high-k dielectric films

Abstract

This disclosure provides (a) methods of making an oxide layer (e.g., a dielectric layer) based on titanium oxide, to suppress the formation of anatase-phase titanium oxide and (b) related devices and structures. A metal-insulator-metal ('MIM') stack is formed using an ozone pretreatment process of a bottom electrode (or other substrate) followed by an ALD process to form a TiOdielectric, rooted in the use of an amide-containing precursor. Following the ALD process, an oxidizing anneal process is applied in a manner is hot enough to heal defects in the TiOdielectric and reduce interface states between TiO2 and electrode; the anneal temperature is selected so as to not be so hot as to disrupt BEL surface roughness. Further process variants may include doping the titanium oxide, pedestal heating during the ALD process to 275-300 degrees Celsius, use of platinum or ruthenium for the BEL, and plural reagent pulses of ozone for each ALD process cycle. The process provides high deposition rates, and the resulting MIM structure has substantially no x-ray diffraction peaks associated with anatase-phase titanium oxide.