Method for Making a FINFET Including a Superlattice
A method for making a semiconductor device may include forming at least one fin field-effect transistor (FINFET) comprising a fin, source and drain regions adjacent opposite sides of the fin, and a gate overlying the fin. The fin may include at least one superlattice including a plurality of stacked groups of layers Each group of layers may include a plurality of stacked base semiconductor monolayers defining a base semiconductor portion, and at least one non-semiconductor monolayer constrained within a crystal lattice of adjacent base semiconductor portions.
1 . A method for making a semiconductor device comprising:
forming at least one fin field-effect transistor (FINFET) comprising a fin, source and drain regions adjacent opposite ends of the fin, and a gate overlying the fin;
the fin comprising at least one superlattice including a plurality of stacked groups of layers, each group of layers comprising a plurality of stacked base semiconductor monolayers defining a base semiconductor portion and at least one non-semiconductor monolayer constrained within a crystal lattice of adjacent base semiconductor portions.
2 . The method of claim 1 further comprising a substrate supporting the at least one FINFET; and wherein the fin comprises a pair of spaced apart superlattices and a semiconductor layer therebetween with groups of layers of each superlattice being stacked in a lateral direction.
3 . The method of claim 1 further comprising a substrate supporting the at least one FINFET; and wherein the fin comprises a single superlattice with groups of layers stacked in a vertical direction.
4 . The method of claim 1 wherein the substrate comprises an uppermost insulator layer supporting the at least one FINFET.
5 . The method of claim 1 wherein the gate comprises a gate dielectric layer and a gate electrode layer overlying the gate dielectric layer.
6 . The method of claim 1 wherein at least one group of layers of the at least one superlattice is substantially undoped.
7 . The method of claim 1 wherein the base semiconductor comprises silicon.
8 . The method of claim 7 wherein the at least one non-semiconductor monolayer comprises oxygen.
9 . The method of claim 1 wherein the at least one non-semiconductor monolayer comprises a non-semiconductor selected from the group consisting essentially of oxygen, nitrogen, fluorine, and carbon-oxygen.
10 . The method of claim 1 wherein the at least one non-semiconductor monolayer is a single monolayer thick.
11 . The method of claim 1 wherein all of the base semiconductor portions are a same number of monolayers thick.
12 . The method of claim 1 wherein at least some of the base semiconductor portions are a different number of monolayers thick.
13 . The method of claim 1 wherein opposing base semiconductor portions in adjacent groups of layers of the at least one superlattice are chemically bound together.
14 . The method of claim 1 wherein the at least one FINFET comprises a plurality of FINFETs.
15 . The method of claim 1 wherein the plurality of FINFETS have different channel conductivities.
16 . The method of claim 1 wherein forming the at least one FINFET comprises forming a plurality thereof defining an inverter.
17 . A method for making a semiconductor device comprising:
forming at least one fin field-effect transistor (FINFET) adjacent a substrate and comprising a fin, source and drain regions adjacent opposite ends of the fin, and a gate overlying the fin;
the fin comprising a pair of spaced apart superlattices and a semiconductor layer therebetween;
each superlattice comprising a plurality of groups of layers stacked in a lateral direction, each group of layers comprising a plurality of stacked base silicon monolayers defining a base silicon portion and at least one oxygen monolayer constrained within a crystal lattice of adjacent base silicon portions.
18 . The method of claim 17 wherein the substrate comprises an uppermost insulator layer supporting the at least one FINFET.
19 . The method of claim 17 wherein the at least one FINFET comprises a plurality of FINFETS having different channel conductivities.
20 . A method for making a semiconductor device comprising:
forming at least one fin field-effect transistor (FINFET) adjacent a substrate and comprising a fin, source and drain regions adjacent opposite ends of the fin, and a gate overlying the fin;
the fin comprising a superlattice including a plurality of groups of layers stacked in a vertical direction, each group of layers comprising a plurality of stacked base silicon monolayers defining a base silicon portion and at least one oxygen monolayer constrained within a crystal lattice of adjacent base silicon portions.
21 . The method of claim 20 wherein the substrate comprises an uppermost dielectric layer supporting the at least one FINFET.
22 . The method of claim 20 wherein the at least one FINFET comprises a plurality of FINFETS having different channel conductivities.