Advanced Organic Polymer for the Aggressive Scaling of Low-k Materials

An advanced organic polymer material of k = 2.2 has been successfully integrated in Cu lines with dielectric spacing from 80 to 20 nm. Cu lines with both TaN/Ta barrier and no barrier were fabricated. Current?voltage (I?V) and time dependent dielectric breakdown (TDDB) measurements were performed to study the scalability of this material. In the case of TaN/Ta barrier, no TDDB degradation was observed at 100 ?C as the dielectric spacing changed from 80 to 30 nm. In the case of no barrier, TDDB performance at 100 ?C was better than that of SiO2 without a barrier. However, TDDB at 200 ?C showed a clear degradation. In contrast, no such degradation was present when TaN/Ta barrier was used.