Replacement metal gate dielectric cap
View Patent ↗A method for manufacturing a field effect transistor includes chelating a molecular mask to a replacement metal gate in a field effect transistor. The method may further include forming a patterned dielectric layer on a bulk dielectric material and a gate dielectric barrier in one or more deposition steps. The method may include removing the molecular mask and exposing part of the gate dielectric barrier before depositing a dielectric cap that touches the gate dielectric barrier and the replacement metal gate.
1. A semiconductor device, comprising:
a replacement metal gate stack for a field effect transistor, having:
a semiconductor substrate with a horizontal surface;
a bulk dielectric material on the horizontal surface;
a replacement metal gate with:
a gate metal having a metal top surface; and
a gate fill with a fill top surface;
a gate oxide on the horizontal surface and surrounding the gate metal;
at least one spacer on the horizontal surface and between the bulk dielectric material and the gate oxide;
a dielectric cap on the metal top surface and the fill top surface, and touching the at least one spacer; and
a seed layer between the at least one spacer and the dielectric cap.
2. The semiconductor device of claim 1 , wherein the seed layer includes aluminum.
3. The semiconductor device of claim 1 , further comprising a patterned dielectric layer directly on the bulk dielectric material.
4. The device of claim 3 , wherein the patterned dielectric layer is made from an oxide selected from a group consisting of silicon dioxide and hafnium oxide.
5. The semiconductor device of claim 1 , wherein a seed layer is between the bulk dielectric material and a patterned dielectric layer.
6. The semiconductor device of claim 5 , further comprising the patterned dielectric layer grown from the seed layer on the bulk dielectric material.