Semiconductor device having a metal gate recess
Provided is a semiconductor device (e.g., transistor such as a FinFET or planar device) having a a liner layer and a metal layer (e.g., Tungsten (W)) in a trench (e.g., via CVD and/or ALD). A single chamber (e.g., an extreme fill chamber) will be utilized to separately etch back the liner layer and the metal layer. In general, the liner layer may be etched back further than the metal layer to provide for larger contact and lower resistance. After etching is complete, a bottom-up fill/growth of metal (e.g., W) will be performed (e.g., via CVD in a W chamber or the like) to increase the presence of gate metal in the trench.
1. A semiconductor device having a metal gate recess, comprising:
a set of trenches formed over a substrate;
a liner layer formed in the set of trenches, the liner layer being formed over a work function metal layer, and the work function metal layer being formed over a high k-layer that is formed over the substrate;
a tungsten (W) layer formed over the liner layer, the liner layer and the W layer being etched to different levels within the trench; and
a bottom-up grown W layer formed in the set of trenches after the etching.
2. The semiconductor device of claim 1 , the liner layer comprising titanium nitride (TiN).
3. The semiconductor device of claim 1 , the liner layer and the W layer being etched in a single etch chamber.