Interaction of Titanium with Silica After Rapid Thermal Annealing in Argon, Nitrogen, and Oxygen

The interaction of Ti with SiO 2 as a result of rapid thermal annealing in argon, nitrogen, and oxygen over a tempetature range of 600° to 1000° has been studied using the analytical techniques of Auger depth profiling, Rutherford backscattering, and X‐ray diffraction. After annealing in argon and nitrogen, Ti 5 Si 3 (with some oxygen) was formed at the Ti/SiO 2 interface at all temperatures in this range. For temperatures below 800° in Ar, an outer uniform layer of α‐Ti with randomly dissolved oxygen or Ti 2 O was formed. At temperatures above 800°, a Ti oxide (O/Ti ratio 1.6) was formed. Annealing in an oxygen ambient showed the formation of rutile with very little reaction of the Ti with SiO 2 . After annealing in nitrogen, a three‐layered structure of TiN/TiO x /Ti 5 Si 3 (with x ≤ 1) was formed, with the relative thickness of each layer dependent upon the annealing temperature. Discussion of the effect of the ambient on the various reactions and diffusion mechanisms is also presented.