Formation of FinFET gate spacer
AssigneeGlobalfoundries Inc.
InventorsDouglas Bonser, Catherine B. Labelle
Life of this patent
Estimating the term…
Abstract
Gate spacers are formed in FinFETS having a bottom portion of a first material extending to the height of the fins, and a top portion of a second material extending above the fins. An embodiment includes forming a fin structure on a substrate, the fin structure having a height and having a top surface and side surfaces, forming a gate substantially perpendicular to the fin structure over a portion of the top and side surfaces, for example over a center portion, forming a planarizing layer over the gate, the fin structure, and the substrate, removing the planarizing layer from the substrate, gate, and fin structure down to the height of the fin structure, and forming spacers on the fin structure and on the planarizing layer, adjacent the gate.
Claims20
A semiconductor device comprising:
- a fin structure on a substrate, the fin structure having a height and having top and side surfaces;
- a gate formed perpendicular to the fin structure over a portion of the top and side surfaces;
- and
- first and second spacers adjacent the gate, the first spacers being formed on the fin structure and the second spacers being formed on the substrate wherein:
- the first spacers are formed of a first material;
- and
- the second spacers comprise a first portion having a height the same as the fin structure and a second portion on top of and in contact with the first portion, the first portion being formed of a second material, different than the first material, and the second portion being formed of the first material.
A device comprising:
- a fin structure on a substrate, the fin structure having a first height and having top and side surfaces;
- a gate formed perpendicular to the fin structure over a portion of the top and side surfaces;
- and
- first gate spacers formed of a first material on the substrate, adjacent the gate, having the first height;
- second gate spacers formed of a second material on the first gate spacers and on the fin structure, adjacent the gate, having a second height, wherein the sum of the first height and the second height equals a height of the gate.
A semiconductor device comprising:
- a fin structure on a substrate, the fin structure having a first height of 10 nm to 60 nm and having top and side surfaces;
- a gate formed perpendicular to the fin structure over a portion of the top and side surfaces, the gate having a bottom portion having a height equal to the first height and a top portion having a second height, wherein a sum of the first height and the second height is 30 nm to 100 nm;
- first spacers formed of a first material comprising spin-on-glass or spin-on-dielectric on the substrate adjacent the bottom portion of the gate and having the first height second spacers formed of a second material comprising an oxide or a nitride on the first spacers and on the fin structure adjacent the top portion of the gate and having the second height, wherein
- a degree of selectivity between the first material and the second material is greater than or equal to about 3 to 1 for etching.
Dependencies are inferred from the claim text.