Composite isolation structures for a fin-type field effect transistor
Structures for the isolation of a fin-type field-effect transistor and methods of forming isolation for a fin-type field-effect transistor. A first dielectric layer is formed that encapsulates a plurality of fins. A second dielectric layer is formed that surrounds the first dielectric layer and the plurality of fins. A surface of the second dielectric layer relative to a surface of the first dielectric layer. A liner is conformally deposited on the surface of the first dielectric layer and on the recessed surface of the second dielectric layer. A section of the liner is removed to expose the surface of the first dielectric layer. The exposed surface of the first dielectric layer is recessed to reveal a portion of each of the plurality of fins.
1. A structure comprising:
a plurality of fins;
a first dielectric layer having a surface arranged to reveal a first portion of each of the plurality of fins and to encapsulate a second portion of each of the plurality of fins beneath the surface;
a second dielectric layer surrounding the first dielectric layer and the plurality of fins, the second dielectric layer having a surface that is coplanar with a portion of the surface of the first dielectric layer;
a first liner including a section arranged horizontally on the surface of the second dielectric layer, the first liner composed of a dielectric material; and
a second liner including a vertical section that is arranged between the first dielectric layer and the second dielectric layer,
wherein the section of the first liner intersects the vertical section of the second liner, and the first liner is absent from the portion of the surface of the first dielectric layer.
2. The structure of claim 1 wherein the surface of the first dielectric layer is planar.
3. The structure of claim 2 wherein each of the plurality of fins includes an active region that is revealed above the surface of the first dielectric layer and an inactive region beneath the surface of the first dielectric layer.
4. The structure of claim 1 wherein the first portion of each of the plurality of fins is an active region, and the second portion of each of the plurality of fins is an inactive region.
5. The structure of claim 1 wherein the section of the first liner and the vertical section of the second liner cover a corner of the second dielectric layer located adjacent to the first dielectric layer.
6. The structure of claim 1 wherein a portion of the first dielectric layer is arranged between the plurality of fins and the vertical section of the second liner.