Microstructure and Surface Topography Evolution of Ti and Ni Thin Structures

Abstract

This paper presents the results of a study of microstructure and surface topography of electron-beam deposited nano-scale (10–500 nm thick) thin films of Ti and Ni. The films are deposited on substrates with different moduli (Ni, NaCl, and Si). The microstructure of each film is characterized using transmission electron microscopy. The surface topography is also studied using atomic force microscopy. The microscopic observations show that the grain size and film roughness increase with increasing film thickness. The grain coarsening observed in Ni films was greater than that observed in Ti films. Furthermore, the effects of coarsening amplitude on (001) oriented NaCl crystals were much greater than those on stiffer (001) oriented silicon substrates. The implications of the results are then discussed for applications of thin films in biomedical engineering, microelectronics, and micro-electro-mechanical systems (MEMS).

Keywords:

• Thin films
• Ti
• Ni
• Microstructure
• Surface topography

Acknowledgments

The research was supported by the Division of Materials Research of the National Science Foundation. The authors are grateful to the NSF Program Manager, Dr. Ulrich Strom, for his encouragement and support. Appreciation is also extended to Profs. Bill Nix and Carl Thompson for useful technical discussions.