Activation Free Electroless Ni for High Aspect Ratio Submicron Vias for Microchip Application

Electroless (EL) processes have been explored for multiple applications in chip manufacturing over last decade. This paper presents the application of EL Ni for via fill. The inherent seam and void in traditional TiN/W processes for high-aspect-ratio vias pose reliability issues. The approach discussed in this article demonstrates that EL Ni is a feasible alternative to TiN/W for high-aspect-ratio vias. The EL Ni fill provides a void-and seam-free fill; it also presents some unique challenges.