Patterning of vertical nanowire transistor channel and gate with directed self assembly
Directed self-assembly (DSA) material, or di-block co-polymer, to pattern features that ultimately define a channel region a gate electrode of a vertical nanowire transistor, potentially based on one lithographic operation. In embodiments, DSA material is confined within a guide opening patterned using convention lithography. In embodiments, channel regions and gate electrode materials are aligned to edges of segregated regions within the DSA material.
1. An integrated circuit structure, comprising:
first and second vertical semiconductor channel structures above a substrate, the first and second vertical semiconductor channel structures each having a sidewall;
an insulating material above the substrate, the insulating material having an opening surrounding the first and second vertical semiconductor channel structures, the opening having a sidewall and a bottom;
a gate dielectric layer on the sidewall and bottom of the opening and on the sidewalls of the first and second vertical semiconductor channel structures; and
a gate electrode in the opening and on the gate dielectric layer, the gate electrode continuous around the first and second vertical semiconductor channel structures.
2. The integrated circuit structure of claim 1 , further comprising:
a semiconductor source structure below the first and second vertical semiconductor channel structures; and
a semiconductor drain structure above the first and second vertical semiconductor channel structures.
3. The integrated circuit structure of claim 1 , further comprising:
a semiconductor drain structure below the first and second vertical semiconductor channel structures; and
a semiconductor source structure above the first and second vertical semiconductor channel structures.
4. The integrated circuit structure of claim 1 , wherein the sidewall opening of the insulating material has a curved portion.
5. The integrated circuit structure of claim 4 , wherein the opening has a substantially oval shape.
6. The integrated circuit structure of claim 1 , wherein the first and second vertical semiconductor channel structures comprise silicon.
7. The integrated circuit structure of claim 1 , wherein the first and second vertical semiconductor channel structures comprise silicon and germanium.
8. The integrated circuit structure of claim 1 , wherein the first and second vertical semiconductor channel structures comprise germanium.
9. The integrated circuit structure of claim 1 , wherein the gate dielectric layer comprises a metal oxide selected from the group consisting of hafnium oxide and zirconium oxide.
10. The integrated circuit structure of claim 1 , wherein the gate electrode comprises a workfunction metal and a fill metal.