TITANIUM-BASED FILMS FORMED BY CHEMICAL VAPOR DEPOSITION

摘要

A gaseous mixture of a titanium halide and silane is introduced to a plasma or thermal CVD reactor to induce a reaction such that a conformal and pure titanium film is deposided onto a semiconductor device within the reactor. The titanium halide has a chemical form of TiX4, where X is a halogen. Other gaseous mixtures of the titanium halide and silane are subjected to plasma or thermal CVD to induce a reaction to deposit titanium silicide films onto the semiconductor device. Hydrogen is sometimes added to the gaseous mixture as a reactant to reduce the silicon content in the resulting titanium silicide layer. Other gaseous combinations of the titanium halide, ammonia, hydrogen, a halogen and silane are subjected to plasma or thermal CVD to induce a reaction to deposit titanium silicide and titanium nitride films onto the semiconductor device. Successive CVD processes create bilayers of TiSix/TiN or Ti/TiN, and/or trilayers of TiSix/Ti/TiN onto the semiconductor device. The invention also includes processes and systems for depositing a titanium-based semiconductor film onto a workpiece surface. A gaseous flow is created and includes a titanium tetrahalide and a hydrogen-bearing gas that is reactive with the titanium halide. This flow is transformed through chemical vapor deposition to deposit the titanium-based film onto the surface. To anneal, the titanium halide is inhibited from the flow so as to remove residual halogen atoms from the surface. The invention provides for annealing of Ti, TiN films, as well as bilayers such as Ti/TiSi2. Plasma and/or thermal CVD are used.