Single diffusion break isolation for gate-all-around field-effect transistor devices
Devices and methods are provided for forming single diffusion break isolation structures for integrated circuit devices including gate-all-around FET devices such as nanosheet FET devices and nanowire FET devices. For example, a semiconductor integrated circuit device includes first and second gate-all-around field-effect transistor devices disposed in first and second device regions, respectively, of a semiconductor substrate. A single diffusion break isolation structure is disposed between the first and second device regions. The single diffusion break isolation structure includes a dummy gate structure disposed on the semiconductor substrate between a first source/drain layer of the first gate-all-around field-effect transistor device and a second source/drain layer of the second gate all-around field-effect transistor device. The single diffusion break isolation structure is configured to electrically isolate the first and second source/drain layers.
1. A semiconductor integrated circuit device, comprising:
a first gate-all-around field-effect transistor device disposed in a first device region of a semiconductor substrate;
a second gate-all-around field-effect transistor device disposed in a second device region of the semiconductor substrate; and
a single diffusion break isolation structure disposed between the first and second device regions;
wherein the single diffusion break isolation structure comprises a dummy gate structure disposed on the semiconductor substrate between a first source/drain layer of the first gate-all-around field-effect transistor device and a second source/drain layer of the second gate all-around field-effect transistor device, wherein the single diffusion break isolation structure is configured to electrically isolate the first and second source/drain layers;
wherein the single diffusion break isolation structure comprises:
a gate sidewall spacer that surrounds and defines a dummy gate region; and
a layer of insulating material disposed in the dummy gate region;
wherein the gate sidewall spacer comprises first embedded sidewall spacers that are in contact with the first and second source/drain layers, wherein the first embedded sidewall spacers comprise a dielectric material comprising silicon and nitrogen, and second embedded sidewall spacers that are in contact with the first and second source/drain layers, wherein the second embedded sidewall spacers comprise oxidized epitaxial silicon material, wherein the second embedded sidewall spacers are disposed between the first embedded sidewall spacers and do not extend into the dummy gate region.
2. The device of claim 1 , wherein the second embedded sidewall spacers comprise oxidized end portions of epitaxial silicon channel layers which remain after removing portions of the epitaxial silicon channel layers from within the dummy gate region such that the dummy gate region is devoid of portions of the epitaxial silicon channel layers.
3. The device of claim 1 , wherein the layer of insulating material disposed in the dummy gate region comprises silicon oxide.
4. The device of claim 1 , wherein the first and second gate-all-around field-effect transistor devices comprise nanosheet field-effect transistor devices.
5. The device of claim 1 , wherein the first and second gate-all-around field-effect transistor devices comprise nanowire field-effect transistor devices.
6. The device of claim 1 , wherein the layer of insulating material completely fills the dummy gate region.
7. The device of claim 1 , wherein the layer of insulating material and the first embedded sidewall spacers comprise different materials.
8. The device of claim 7 , wherein the layer of insulating material comprises silicon oxide and wherein the first embedded sidewall spacers comprise silicon nitride.
9. The device of claim 1 , wherein the layer of insulating material and the first embedded sidewall spacers comprise a same material.
10. The device of claim 1 , wherein the layer of insulating material and the first embedded sidewall spacers comprise silicon nitride.
11. The device of claim 1 , wherein the first embedded sidewall spacers comprise one of SiN, SiBCN, SiBCN, and SiCON.
12. The device of claim 1 , wherein the layer of insulating material comprises one of silicon nitride, silicon oxynitride, SiCOH, SiCH, and SiCNH.