Published online by Cambridge University Press: 21 February 2011
A strong correlation has been established between TiN substrate anneal ambient and electromigration performance of Al-based alloys. Excellent electromigration lifetimes were measured for AlSiCu (and AlCu) films on sputtered TiN substrates annealed in N2 and slowly cooled down in furnace. The films annealed in N2-O2 and N2-H2 showed poorer electromigration performance, in that order. Stronger Al (111) texture, larger median grain size and uniform grain size distribution have been responsible for the improved electromigration performance of the N2-annealed (furnace-cooled) films. On the contrary, Al alloy films on TiN substrates annealed in N2 (but air-cooled), N2-O2, or N2-H2 ambient showed weaker Al (111) textures and smaller median grain sizes.