Title :
Effects of NH3-plasma nitridation on the electrical characterizations of low-k hydrogen silsesquioxane with copper interconnects
Author :
Liu, Po-Tsun ; Chang, Ting-Chang ; Yang, Ya-Liang ; Cheng, Yi-Fang ; Sze, Simon M.
Author_Institution :
Nat. Nano Device Lab., Hsinchu, Taiwan
fDate :
9/1/2000 12:00:00 AM
Abstract :
The interaction between copper interconnects and low-k hydrogen silsesquioxane (HSQ) film was investigated using a Cu/HSQ/Si metal insulation semiconductor capacitor and NH3 plasma post-treatment. Owing to serious diffusion of copper atoms in HSQ film, degradations of the dielectric properties are significant with the increase of thermal stress. The leakage current behavior in high field conduction is well explained by the Poole-Frenkel (P-F) mechanism. By applying NH3-plasma treatment to the HSQ film, however, the leakage current is decreased and P-F conduction can be significantly suppressed. In addition, the phenomenon of serious Cu penetration is not observed by means of electrical characteristic measurements and secondary ion mass spectroscopy (SIMS) analysis even in the absence of diffusion barrier layers. This indicates the copper diffusion in low-k HSQ film can he effectively blocked by NH3 plasma post-treatment
Keywords :
MIS capacitors; Poole-Frenkel effect; copper; dielectric thin films; diffusion; hydrogen compounds; integrated circuit interconnections; leakage currents; nitridation; plasma materials processing; secondary ion mass spectra; Cu-HSiO-Si; Cu/HSQ/Si MIS capacitor; NH3; NH3 plasma nitridation; Poole-Frenkel leakage current; copper diffusion; copper interconnect; electrical characteristics; high field conduction; hydrogen silsesquioxane film; low-k intermetal dielectric; multilevel metallization; secondary ion mass spectroscopy; thermal stress; Capacitors; Copper; Dielectrics and electrical insulation; Hydrogen; Leakage current; Plasma measurements; Plasma properties; Semiconductor films; Thermal degradation; Thermal stresses;
Journal_Title :
Electron Devices, IEEE Transactions on
