Measurement of Angular Emission Trajectories for Magnetron-Sputtered Tantalum
Authors: Wickersham, C.E.; Zhang, Zhiguo
Source: Journal of Electronic Materials, Volume 34, Number 12, December 2005 , pp. 1474-1479(6)
Abstract:Sputtering target crystallographic orientation affects film deposition uniformity through the emission trajectories of the sputtered atoms. Understanding the relationship between the crystallographic orientation of the sputtering target and the emission trajectory for the sputtered atoms is important for being able to accurately model film thickness uniformity and step coverage. This paper describes the measurement of atom sputter trajectory from a tantalum single crystal. A quartz crystal monitor is used to detect sputter atom flux as a function of angle. The angular sputter emission measurements are consistent with emission from tantalum single crystals along the <111> close-packed direction as well as the second close-packed <100> direction. Best fit of the experimental data occurs when the ratio of the emission probabilities in the <111> and <100> directions (P<111>/P<100>) is 1.4, and the ratio of the major and minor axis for the sputter emission ellipsoid (the b/a ratio) is 1.5.
Document Type: Research Article
Publication date: December 2005