The present invention generally relates to filling of a feature by
depositing a barrier layer, depositing a seed layer over the barrier
layer, and depositing a conductive layer over the seed layer. In one
embodiment, the seed layer comprises a copper alloy seed layer deposited
over the barrier layer. For example, the copper alloy seed layer may
comprise copper and a metal, such as aluminum, magnesium, titanium,
zirconium, tin, and combinations thereof. In another embodiment, the seed
layer comprises a copper alloy seed layer deposited over the barrier
layer and a second seed layer deposited over the copper alloy seed layer.
The copper alloy seed layer may comprise copper and a metal, such as
aluminum, magnesium, titanium, zirconium, tin, and combinations thereof.
The second seed layer may comprise a metal, such as undoped copper. In
still another embodiment, the seed layer comprises a first seed layer and
a second seed layer. The first seed layer may comprise a metal, such as
aluminum, magnesium, titanium, zirconium, tin, and combinations thereof.
The second seed layer may comprise a metal, such as undoped copper.