講演情報
[17a-S2_201-7]Substrate-Dependent Ruthenium Electrodeposition for Interconnect Applications
〇(D)Zhitao Hu1, Kurioka Tomoyuki1, Yung-Jung Hsu1,2, Tso-Fu Mark Chang1, Katsuyuki Machida1, Hiroyuki Ito1, Miyake Yoshihiro1, Masato Sone1 (1.Science Tokyo, 2.NYCU)
キーワード：
ruthenium、electrochemical deposition、interconnect materials
As integrated circuit (IC) devices continue to scale, the stability of metal interconnects has become a critical performance bottleneck. Conventional copper (Cu) interconnects suffer from increased resistivity, poor electromigration reliability, and the need for thick diffusion barriers at nanoscale dimensions. Ruthenium (Ru) is considered a promising alternative due to its weak size-dependent resistivity and good electromigration resistance. However, Ru electrodeposition is strongly affected by hydrogen evolution and electrogenerated base, which reduce deposition efficiency and promote oxide formation.In this study, galvanostatic electrodeposition was used to investigate the substrate-dependent deposition behavior of Ru on IC-relevant metals. X-ray diffraction reveals the formation of crystalline RuO2 on Cu substrates (2θ ≈ 28°), while no RuO2 phase is detected on Ti or Ni under identical conditions. Among the tested substrates, Ti exhibits the highest current efficiency, likely due to suppressed hydrogen evolution. These results demonstrate that substrate selection critically influences phase formation and side reactions during Ru electrodeposition, providing insight for the integration of Ru interconnects into Si-based processes.