A 0.7-μm-pitch double level Al interconnection technology for 1-Gbit DRAMs using SiO2 mask Al etching and plasma enhanced chemical vapor deposition SiOF

Takashi Yokoyama, Yoshiaki Yamada, Koji Kishimoto, Tatsuya Usami, Hideaki Kawamoto, Kazuyoshi Ueno, Hideki Gomi

Research output: Contribution to journalArticle


A 0.7-μm-pitch double level aluminum (Al) interconnection technology on a 1-μm-high step is established for 1-Gbit dynamic random access memories (DRAMs). A SiO2 film which has a high resistance to Al etching was used as the mask layer. 0.35-μm-width Al wirings were fabricated even on a 1-μm-high step. 0.2-μm-spaces (aspect ratio=2.5) between the taper shaped Al lines were filled, for the first time, by a plasma enhanced chemical vapor deposition (PECVD) fluorine doped silicon oxide (SiOF) film (ε=3.9). The SiOF film capped with the PECVD SiO2 film has enough stability for the process integration. It was confirmed that these technologies can be applied to a double level Al interconnection using a 0.3-μm-diameter tungsten (W) plug.

Original languageEnglish
Pages (from-to)1140-1144
Number of pages5
JournalJapanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers
Issue number3 SUPPL. B
Publication statusPublished - 1998 Mar 1



  • Al etching
  • DRAM
  • Photoresist
  • SiO
  • SiOF
  • Step height

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

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