| 초록 |
The space between Cu interconnects in integrated circuits have been continuously reduced to increase the packing density of semiconductors. The insulation of Cu wires with porous ultralow dielectrics (ULK, k ~ 2.2) has been undertaken to solve RC delay, but the tough challenges still remain. One of these challenges is plasma-induced damage (PID) during BEOL process which leads to shrinkage and dielectric loss. To improve the PID resistance, we have studied the 2 types of protection strategies: using pre-porous ULK with reactive cyclodextrin molecules and refilling the ULK nanopores with oligomeric polystyrene which called porosity last and pore-stuffing, respectively. The protection level was characterized by thickness, structures and topologies changes and compared to unprotected ULK. It is noteworthy that the PID was remarkably decreased after protection process. These approaches may pave the way to overcoming the integration limitation. |
