Title :
A quarter-micrometer interconnection technology using a TiN/Al-Si-Cu/TiN/Al-Si-Cu/TiN/Ti multilayer structure
Author :
Kikkawa, Takamaro ; Aoki, Hidemitsu ; Ikawa, Eiji ; Drynan, John M.
Author_Institution :
NEC Corp., Sagamihara, Japan
fDate :
2/1/1993 12:00:00 AM
Abstract :
An interconnection structure using a TiN/Al-1% Si-0.5% Cu/TiN/Al-1% Si-0.5% Cu/TiN/Ti multilayer conductor was investigated as a quarter-micrometer interconnection candidate for 256-Mb DRAMs. It was found that intermetallic compounds such as TiAlx were formed at both grain boundaries of Al-Si-Cu and interfaces between Al-Si-Cu and TiN of the multilayer, resulting in both increase in Vickers hardness and suppression of stress relaxation. The multilayer conductor strip, which was covered with plasma-enhanced chemical vapor deposition silicon nitride (P-SiN), suppressed stress-induced voiding after heat treatment at 500°C. Electromigration tests for quarter-micrometer wide multilayer strips indicated the improvement in the mean time to failure and the increase of the standard deviation
Keywords :
aluminium alloys; chemical interdiffusion; copper alloys; electromigration; failure analysis; integrated circuit technology; metallisation; silicon alloys; titanium; titanium compounds; 0.25 micron; 500 degC; DRAMs; SiN; TiAlx; TiN-AlSiCu-TiN-AlSiCu-TiN-Ti multilayer structure; Vickers hardness; electromigration tests; grain boundaries; heat treatment; interconnection technology; intermetallic compounds; mean time to failure; multilayer conductor strip; plasma-enhanced chemical vapor deposition; stress relaxation suppression; stress-induced voiding; Chemical vapor deposition; Conductors; Grain boundaries; Intermetallic; Nonhomogeneous media; Plasma chemistry; Silicon; Stress; Strips; Tin;
Journal_Title :
Electron Devices, IEEE Transactions on
