Effect of H2O on TDDB for a range of ULK ILD materials with varying damage resistance for robust and weak liners
In this study we look at the correlation between TDDB lifetime, in the presence of intentionally introduced H2O and top surface damage for different ILD materials using a robust liner. The activation energy for the movement of loosely bound physi-adsorbed H2O has been obtained using AC loss measurements. We also explore the role of moisture in drawing Cu out of metal lines through an intentionally-fabricated thin/weak liner under prolonged stress at a relatively low voltage. AC loss, I-V, triangular voltage sweep (TVS) and TDDB measurements all provide evidence that Cu is migrating out of the lines into the ILD.