The formation of thin amorphous cobalt titanium nitride (CoTiN) layers was investigated using a supercycle method of atomic layer deposition (ALD). The stoichiometry of the resultant ALD CoTiN films was controlled by changing the ratio of Co and TiN thicknesses. X-ray diffraction analysis and transmission electron microscopy observations showed that the microstructure of the ALD Co and TiN was transformed from polycrystalline to amorphous CoTiN. The stoichiometry of the CoTiN layer was affected by the growth characteristics of ALD Co and TiN on each surface. The results revealed that ALD TiN undergoes nucleation incubation on the ALD Co surface, whereas ALD Co does not undergo nucleation incubation on the ALD TiN surface. The properties of the amorphous CoTiN layers were evaluated by diffusion experiments and mechanical tests. Because of the lack of grain boundaries, the CoTiN efficiently blocks the diffusion of Cu at elevated temperatures and exhibits higher hardness compared with ALD Co.
Bibliographical noteFunding Information:
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education ( 2016R1D1A1B03935611 ), the Korean government ( MSIP: Ministry of Science, ICT and Future Planning ) ( 2016M2B2A9A02944647 ), and by Korea Evaluation Institute of Industrial Technology (KEIT) funded by the Ministry of Trade, Industry and Energy (MOTIE) (Project No. 10080642 ). Our sincere thanks go to Dow Chemical for their contribution to the preparation of the Co(AMD) 2 precursor.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry