Title :
Low contact resistance metallization for gigabit scale DRAM´s using fully-dry cleaning by Ar/H2 ECR plasma
Author :
Taguwa, Tetsuya ; Urabe, Koji ; Sekine, Makoto ; Yamada, Yoshiaki ; Kikkawa, Takamaro
Author_Institution :
ULSI Device Dev. Lab., NEC Corp., Kanagawa, Japan
fDate :
4/1/1997 12:00:00 AM
Abstract :
A fully-dry cleaning technique with Ar/H2 Electron Cyclotron Resonance (ECR) plasma was developed as a low contact resistance metallization technology for gigabit scale DRAM contacts. By combining with ECR TiN/Ti-CVD, extremely low contact resistances of 296 Ω and 350 Ω for 0.3-μm contact diameter with aspect ratio of 7 were realized on n+ and p+ diffusion layers, respectively. No leakage current was observed. By using this technology, a DRAM ULSI, which was planarized by Chemical Mechanical Polishing (CMP) and had deep contact holes with aspect ratio of 6, was successfully demonstrated
Keywords :
DRAM chips; ULSI; contact resistance; integrated circuit metallisation; polishing; surface cleaning; 0.3 micron; 296 ohm; 350 ohm; Ar; Ar-H2; ECR plasma; H2; ULSI; aspect ratio; chemical mechanical polishing; contact diameter; contact resistance; deep contact holes; fully-dry cleaning; gigabit scale DRAM; metallization; Argon; Chemical technology; Cleaning; Contact resistance; Cyclotrons; Electrons; Metallization; Plasmas; Random access memory; Resonance;
Journal_Title :
Electron Devices, IEEE Transactions on
