1. Low Temperature Two-Step Atomic Layer Deposition of Tantalum Nitride for Cu Diffusion Barrier
- Author
-
Do-Geun Kim, Jae-Wook Kang, Jong-Kuk Kim, Jung-Dae Kwon, Kee-Seok Nam, Se-Hun Kwon, Jong-Joo Rha, and Seong-Jun Jeong
- Subjects
Materials science ,Diffusion barrier ,Renewable Energy, Sustainability and the Environment ,Inorganic chemistry ,Tantalum ,chemistry.chemical_element ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Tantalum pentafluoride ,Atomic layer deposition ,chemistry.chemical_compound ,Tantalum nitride ,chemistry ,Electrical resistivity and conductivity ,Materials Chemistry ,Electrochemistry ,Thin film ,Deposition (chemistry) - Abstract
A cubic δ-TaN thin film with an electrical resistivity of 400 μΩ cm was successfully obtained by suppressing the formation of Ta 3 N 5 using two-step atomic layer deposition independent of NH 3 dosage. The deposition cycle involved two chemical reaction steps: The formation of elemental tantalum (Ta) by reducing tantalum pentafluoride (TaF 5 ) with hydrogen plasma and the subsequent nitridation of the preformed Ta with NH 3 at 200―350°C. The microstructure of the preformed Ta was β-Ta phase with an electrical resistivity of 220 μΩ cm, which was formed without regard to the deposition temperature. At a deposition temperature of less than 250°C, cubic δ-TaN with a Ta/N ratio of I was achieved independent of the NH 3 dosage. However, at a deposition temperature of greater than 300°C, the resistivity of Ta―N-based thin film increased abruptly as the NH 3 dosage exceeded 16.08 × 10 19 molecules/cm 3 due to the formation of Ta 3 N 5 .
- Published
- 2009
- Full Text
- View/download PDF