A new enhancement layer to improve copper interconnect performance
This study reports the effect of different barrier on Cu interconnect performance. A thin “enhancement” layer of Ru or Co film is deposited between a PVD Ta(N) liner barrier and a Cu seed layer to improve copper to barrier adhesion and copper gap fill. With the enhancement layer of either Ru or Co, no void is found in dual damascene structure with very thin seed. The electrical performance is improved with more than two times of EM lifetime is observed. The seedless electroplating on the enhancement layers capability will maximize the gap fill window. authors: Hung Yi Huang, C. H. Hsieh, S. M. Jeng, H. J. Tao, Min Cao, Y. J. Mii
Interconnect
On-chip Interconnect
On-chip interconnect today is based on copper/low-k wiring – in today’s chips, there can be more than 100 km of copper wires.
TSMC’s leading edge technologies use a novel copper gap-fill solution to enable the fabrication of smaller conductor lines. Newly-developed materials and processes allow significant reduction in line and via resistance to improve chip performance. A comprehensive suite of innovations on integration scheme, low-k material, and low-k process with selective deposition further enhance both performance (through capacitance reduction) and reliability. Beyond copper interconnect, explorations of single metallic elements, binary and ternary alloys, and 2D materials for future interconnect materials are underway both within TSMC and with our academic partners.
