Semiconductor device replacement metal gate with gate cut last in RMG

A method for making a semiconductor structure, the method comprising:

• providing a starting semiconductor device having a fin structure patterned in a substrate, and a gate formed over the fin structure, the gate having a mid-region and an end-region;
• patterning a first trench in a mask over the mid-region of the gate and a second trench in the mask over the end-region of the gate;
• etching, using the mask, a first trench in the mid-region of the gate and a second trench in the end-region of the gate, the first trench and the second trench being separate trenches formed in different regions of the gate, the first trench comprising a bottom wall formed of the substrate and a plurality of sidewalls formed of a gate metal and a work function metal stack, and the second trench comprising a bottom wall formed of the substrate, a first sidewall formed of a gate spacer, and a second sidewall formed of the gate metal and the work function metal stack;
• and
• depositing a conformal low-k dielectric layer over the structure to fill the first trench and the second trench, and pinch off the first trench formed in the mid-region and the second trench formed in the end-region.