Substrate rotation effect over scaling roughness exponents in Zr thin films grown by GLAD technique

Abstract

In this work, roughness scaling behavior of glancing angle deposited Zr thin films by DC magnetron sputtering at different substrate rotation speeds, have been studied using height-height correlation function (HHCF) and power spectral density (PSD) function analysis, from atomic force microscopy scans. The Zr thin films exhibit a local roughness exponent close to the unity. However, the growth exponent increases with rotation speed from 0.9 to 1.1. The PSD plot exhibits a characteristic peak, indicating a mound-like growth. Distance between mounds (characteristic length) decreases as rotation increases, demonstrating a reduction of the shadowing effect. It is concluded that the increase of beta is due to the remission process. Incoming atoms lose more kinetic energy when colliding with a substrate in motion, which leads an increase in the sticking coefficient.