Field effect transistor devices with self-aligned source/drain contacts and gate contacts positioned over active transistors
A method of forming a transistor device is provided. The method includes forming a plurality of gate structures including a gate spacer and a gate electrode on a substrate, wherein the plurality of gate structures are separated from each other by a source/drain contact. The method further includes reducing the height of the gate electrodes to form gate troughs, and forming a gate liner on the gate electrodes and gate spacers. The method further includes forming a gate cap on the gate liner, and reducing the height of the source/drain contacts between the gate structures to form a source/drain trough. The method further includes forming a source/drain liner on the source/drain contacts and gate spacers, wherein the source/drain liner is selectively etchable relative to the gate liner, and forming a source/drain cap on the source/drain liner.
1. A method of forming a transistor device, comprising:
forming a plurality of gate structures including a gate spacer and a gate electrode on a substrate, wherein the plurality of gate structures are separated from each other by a source/drain contact;
reducing the height of the gate electrodes to form gate troughs;
forming a gate liner on the gate electrodes and gate spacers;
forming a gate cap on the gate liner;
reducing the height of the source/drain contacts between the gate structures to form a source/drain trough;
forming a source/drain liner on the source/drain contacts and gate spacers, wherein the source/drain liner is selectively etchable relative to the gate liner; and
forming a source/drain cap on the source/drain liner.
2. The method of claim 1 , wherein source/drains are in the substrate, and each of the source/drain contacts is in electrical contact with one of the source/drains.
3. The method of claim 1 , further comprising forming a patterned lower mask layer on at least a portion of the gate caps and gate liners, wherein a portion of the source/drain caps and source/drain liners are exposed.
4. The method of claim 3 , further comprising removing the exposed portion of the source/drain caps, and removing a portion of the source/drain liners.
5. The method of claim 1 , further comprising forming a patterned lower mask layer on at least a portion of the source/drain caps and source/drain liners, wherein a portion of the gate caps and gate liners are exposed.
6. The method of claim 5 , further comprising removing the exposed portion of the gate caps, and removing a portion of the gate liners.
7. The method of claim 1 , wherein the source/drain liners are a metal oxide selected from the group consisting of aluminum oxide (AlO), hafnium oxide (HfO), zirconium oxide (ZrO), titanium oxide (TiO), tantalum oxide (TaO), niobium oxide (NbO), and combinations thereof.
8. The method of claim 7 , wherein the gate liners are a metal oxide selected from the group consisting of aluminum oxide (AlO), hafnium oxide (HfO), zirconium oxide (ZrO), titanium oxide (TiO), tantalum oxide (TaO), niobium oxide (NbO), and combinations thereof, and the gate liners are a different metal oxide from the source/drain liners.
9. The method of claim 8 , wherein the gate caps are a hardmask material selected from the group consisting of silicon nitride (SiN), silicon oxynitride (SiON), silicon carbide (SiC), silicon carbonitride (SiCN), silicon boronitride (SiBN), silicon borocarbide (SiBC), silicon boro carbonitride (SiBCN), and combinations thereof.
10. The method of claim 9 , wherein the source/drain caps are a hardmask material selected from the group consisting of silicon nitride (SiN), silicon oxynitride (SiON), silicon carbide (SiC), silicon carbonitride (SiCN), silicon boronitride (SiBN), silicon borocarbide (SiBC), silicon boro carbonitride (SiBCN), and combinations thereof, and the gate caps are a different hardmask material from the source/drain caps.
11. The method of claim 10 , wherein the gate spacers are a silicon based dielectric material selected from the group consisting of silicon oxy boro carbon nitride (SiOBCN), silicon oxy carbo nitride (SiOCN), silicon boro carbonitride (SIBCN), silicon carbonitride (SiCN), and combinations thereof.
12. A method of forming a transistor device, comprising:
forming a plurality of gate structures including a gate spacer and a gate electrode on a substrate, wherein the plurality of gate structures are separated from each other by a source/drain contact;
reducing the height of the gate electrodes to form gate troughs;
forming a gate liner on the gate electrodes and gate spacers;
forming a gate cap on the gate liner;
reducing the height of the source/drain contacts between the gate structures to form a source/drain trough;
forming a source/drain liner on the source/drain contacts and gate spacers, wherein the source/drain liner is selectively etchable relative to the gate liner;
forming a source/drain cap on the source/drain liner;
forming a patterned lower mask layer on the source/drain caps and gate caps, wherein a source/drain trench exposes a portion of each of the source/drain caps in a staggered arrangement; and
removing the exposed portions of the source/drain caps, and the underlying portions of the source/drain liners.
13. The method of claim 12 , further comprising forming a source/drain lead in each of the source/drain trenches.
14. The method of claim 13 , further comprising forming at least one gate trench in the lower mask layer that exposes a portion of at least one of the gate caps; and
removing the exposed portion of the at least one gate cap, and the underlying portion of the gate liner.
15. The method of claim 14 , further comprising forming a gate contact in the at least one gate trench.