A bilayer diffusion barrier of ALD-Ru/ALD-TaCN for direct plating of Cu

Soo Hyun Kim, Hyun Tae Kim, Sung Soo Yim, Do Joong Lee, Ki Su Kim, Hyun Mi Kim, Ki Bum Kim, Hyunchul Sohn

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

Diffusion barrier performances of atomic layer deposited (ALD)-Ru thin films between Cu and Si were improved with the use of an underlying 2 nm thick ALD-TaCN interlayer as diffusion barrier for the direct plating of Cu. Ru was deposited by a sequential supply of bis(ethylcyclopentadienyl)ruthenium [Ru (EtCp) 2] and NH3 plasma and TaCN by a sequential supply of (NEt2) 3 Ta= Nbut (tert-butylimido-trisdiethylamido-tantalum), and H2 plasma. Sheet resistance measurements, X-ray diffractometry, and Auger electron spectroscopy analysis showed that the bilayer diffusion barriers of ALD-Ru (12 nm)/ALD-TaCN (2 nm) and ALD-Ru (4 nm)/ALD-TaCN (2 nm) prevented the Cu diffusion up to annealing temperatures of 600 and 550°C for 30 min, respectively. This is because of the excellent diffusion barrier performance of the ALD-TaCN film against the Cu, due to its amorphous structure. A 5 nm thick ALD-TaCN film was even stable up to annealing at 650°C between Cu and Si. Transmission electron microscopy investigation, combined with energy-dispersive spectroscopy analysis, revealed that the ALD-Ru/ALD-TaCN diffusion barrier failed by the Cu diffusion through the bilayer into the Si substrate. This is due to the ALD-TaCN interlayer preventing the interfacial reaction between the Ru and Si.

Original languageEnglish
Pages (from-to)H589-H594
JournalJournal of the Electrochemical Society
Volume155
Issue number8
DOIs
Publication statusPublished - 2008 Jul 11

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Renewable Energy, Sustainability and the Environment
  • Surfaces, Coatings and Films
  • Electrochemistry
  • Materials Chemistry

Fingerprint Dive into the research topics of 'A bilayer diffusion barrier of ALD-Ru/ALD-TaCN for direct plating of Cu'. Together they form a unique fingerprint.

  • Cite this

    Kim, S. H., Kim, H. T., Yim, S. S., Lee, D. J., Kim, K. S., Kim, H. M., Kim, K. B., & Sohn, H. (2008). A bilayer diffusion barrier of ALD-Ru/ALD-TaCN for direct plating of Cu. Journal of the Electrochemical Society, 155(8), H589-H594. https://doi.org/10.1149/1.2940447