Chemical Mechanical Polishing of a Ti-Si-N Nanocomposite and AFM Study on Its Nanostructure

Hyunseop Lee, Doo-In Kim, Haedo Jeong and Kwang Ho Kim

J. Korean Phys.Soc. 57,845 [doi: 10.3938/jkps.57.845 | PDF Download]

Ti-Si-N films were characterized as a nanocomposite, consisting of cubic titanium nitride (TiN) nanocrystallites embedded in an amorphous matrix of silicon nitride (Si3N4). Ti-Si-N films have been used as an anti-wear coating due to their mechanical properties and a diffusion barrier for copper metallization in semiconductor processing. The surface of Ti-Si-N is so rough that it is hard to characterize its nanostructure with an atomic force microscope (AFM). Therefore, Ti-Si-N surface should be polished and smoothened to reduce its roughness before AFM study. In this study, we investigated chemical mechanical polishing (CMP) process for preparing AFM study on Ti-Si-N nanostructure by using two different types of CMP slurries. Then the characterization of TiN embedded in Si3N4 matrix was conducted by tapping mode AFM and phase shift imaging.