Thin Solid Films, Vol.462-63, 275-278, 2004
The use of electroless copper seed in electrochemical deposited copper interconnect
Copper (Cu) electroplating (EP) process requires a Cu seed to conduct the current. Conventional physical vapor deposition (PVD) seed suffers from poor step coverage while chemical vapor deposition (CVD) seed is cost-ineffective. We therefore propose the use of electroless (EL) technique as a Cu seed deposition method and demonstrate its integration with conventional Cu EP. The EL seed has excellent step coverage which when combined with the bottom-up fill capability of additives-based EP process, produces void-free fill. The EL seed-EP Cu film stack has good resistivity, roughness and acceptable (I 11) texture. However, some adhesion issues remain to be solved for this integration scheme. (C) 2004 Elsevier B.V. All rights reserved.