Dielectric Passivation and Geometry Effects on the Electromigration Characteristics in Al - 1% Si Thin Film Interconnections = Dielectric Passivation and Geometry Effects on the Electromigration Characteristics in Al - 1% Si Thin Film Interconnections

다국어 초록 (Multilingual Abstract)

Dielectric passivation effects on the EM(electromigration) have been a great interest with recent ULSI and multilevel structure trends in thin film interconnections of a microelectronic device. SiO₂, PSG(phosphosilicate glass), and Si₃N₄ passivation materials effects on the EM resistance were investigated by utilizing widely used Al-1%Si thin film interconnections. A standard photolithography process was applied for the fabrication of 0.7 ㎛ thick, 3 ㎛ wide, and 200㎛~1600 ㎛ long Al-1%Si EM test patterns. SiO₂, PSG, and Si₃N₄ dielectric passivation with the thickness of 300 ㎚ were singly deposited onto the Al-1%Si thin film interconnections by using an APCVD(atmospheric pressure chemical vapor deposition) and a PECVD(plasma enhanced chemical vapor deposition) in order to investigate the passivation materials effects on the EM characteristics. EM tests were performed at the direct current densities of 3.2×10^6~4.5×10^6 A/㎤ and at the temperatures of 180 ℃, 210 ℃, 240 ℃, and 270 ℃ for measuring the activation energies(Q) and for accelerated test conditions. Activation energies were calculated from the measured MTF(mean-time-to-failure) values. The calculated activation energies for the electromigration were 0.44 eV, 0.45 eV, and 0.50 eV, and 0.66 eV for the case of nonpassivated-, Si3N4 passivated-, PSG passivated-, and SiO₂ passivated Al-1%Si thin film interconnections, respectively. Thus SiO₂ passivation showed the best characteristics on the EM resistance followed by the order of PSG, Si₃N₄, and nonpassivation. It is believed that the passivation sequences as well as the passivation materials also influence on the EM characteristics in multilevel passivation structures.

목차 (Table of Contents)

• Abstract
  
• Ⅰ. Introduction
  
• Ⅱ. Experiment
  
• Ⅲ. Results and discussion
  
• Ⅳ. Conclusion
  
• Acknowledgements
  
• References