Low temperature TiN deposition by ICP-assisted chemical vapor deposition

TiN films were deposited by inductively coupled plasma (ICP)-assisted CVD using a gas mixture of TiCl4, H2, Ar and N2 with a substrate temperature of 400 °C and room temperature. For ICP generation, r.f. power was applied using a dielectric-encapsulated coil antenna installed inside the deposition chamber. The ICP power was varied from 100 to 400 W. The deposition rate was as high as >1 μm/h in most deposition conditions. As the r.f. power was increased, the deposition rate decreased irrespective of the deposition temperature. It is believed that the decrease in the deposition rate at higher ICP powers is due to resputtering of the coatings as a result of ion bombardment as well as film densification. The hardness increased with increasing r.f. power, indicating the formation of a denser film at higher power. The decrease in the resistivity at high powers is related to the low Cl content in the film. The TiN film deposited by ICP-assisted CVD showed also a good step coverage on the trenches with a high aspect ratio.