Published online by Cambridge University Press: 21 February 2011
Re-emissions from surfaces receiving a ballistically transported molecular flux have, in the most general case, a spatial distribution with a combination of specular and diffuse components. The addition of specular transmission in the EVOLVE model allows combined specular-diffuse re-emission to be explicitly modeled. Previous modeling of the step-coverage of sputtered titanium nitride (TiN) films in contact structures produced good predictions with a sub-unity sticking coefficient, 0.6 in value, using a strictly diffuse formulation for material re-emission. New data of collimated sputtered TiN with contact aspect ratios exceeding 4.0 was modeled using the EVOLVE specular-diffuse formulation. The result was more accurate model predictions of experimental data and replacement of the ad hoc empirical parameter adjustment in previous modeling with a more detailed physical description.