We investigated the aluminum wiring reliability of fluorinated amorphous carbon (a-C:F) interlayer dielectrics (ILD) using electromigration tests at the wafer level under accelerated stress conditions with current density ranging from 2 - 32 MA/cm~2 and a the substrate temperature of 300K. The a-C:F film is one of the low-k organic materials with a dielectric constant of 2.5. The thermal conductivity of the a-C:F film (0.108 W/m centre dot K). We found that joule heating effect is enhanced by the lower thermal conductivity of a-C:F and that the wiring lifetime for a -C:F ILD is about one order lower than that for SiO_2 ILD under high current stress. However, when the wiring lifetime is plotted as a function of the wiring temperature, the wiring lifetimes for both a-C:F ILD and SiO_2 ILD became almost the same. The degradation of the wiring lifetime for a-C:F ILD is explained by the increase of the wiring temeprature which is caused from joule heating. Moreover, the activation energy of the electromigration fro a -C:F ILD has the same value as that of SiO_2 ILD at a temperature.
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