FORMING DEFECT-FREE RELAXED SiGe FINS
A method of forming defect-free relaxed SiGe fins is provided. Embodiments include forming fully strained defect-free SiGe fins on a first portion of a Si substrate; forming Si fins on a second portion of the Si substrate; forming STI regions between adjacent SiGe fins and Si fins; forming a cladding layer over top and side surfaces of the SiGe fins and the Si fins and over the STI regions in the second portion of the Si substrate; recessing the STI regions on the first portion of the Si substrate, revealing a bottom portion of the SiGe fins; implanting dopant into the Si substrate below the SiGe fins; and annealing.
1 . A device comprising:
strained silicon germanium (SiGe) fins, each having a top portion and a bottom portion, on a first portion of a silicon (Si) substrate;
Si fins, each having a top portion and a bottom portion, on a second portion of the Si substrate;
shallow trench isolation (STI) regions between adjacent SiGe fins and Si fins, the STI regions being below a bottom surface of the SiGe fins and below the top portion of the Si fins;
a cladding layer over top and side surfaces of the top portions of the SiGe fins and the Si fins and over the STI regions in the second portion of the Si substrate; and
a dopant implanted into the Si substrate below the SiGe fins.
2 . The device according to claim 1 , wherein the SiGe fins comprise a first SiGe material over a second SiGe material.
3 . The device according to claim 2 , wherein the first SiGe material has a higher concentration of germanium (Ge) than the second SiGe material.
4 . The device according to claim 3 , wherein the Si fins comprise a Si material over the second SiGe material.
5 . The device according to claim 1 , wherein the dopant is implanted in the Si substrate under the second SiGe material of the Si fins and under the SiGe fins.
6 . The device according to claim 1 , wherein the cladding layer comprises nitride, oxynitride, low-k dielectric material, or silicon oxycarbide (SiOC).
7 . A device comprising:
strained silicon germanium (SiGe) fins on a first portion of a silicon (Si) substrate;
Si fins on a second portion of the Si substrate;
shallow trench isolation (STI) regions between adjacent SiGe fins and Si fins; and
a cladding layer over top and side surfaces of the SiGe fins and the Si fins and over the STI regions in the second portion of the Si substrate,
wherein a bottom portion of the SiGe fins is oxidized.
8 . The device according to claim 7 , wherein the SiGe fins comprise a first SiGe material over a second SiGe material.
9 . The device according to claim 8 , wherein the first SiGe material has a higher concentration of germanium (Ge) than the second SiGe material.
10 . The device according to claim 9 , wherein the Si fins comprise a Si material over the second SiGe material.
11 . The device according to claim 7 , wherein a bottom portion of the second SiGe material of both the SiGe fins and the Si fins is oxidized.
12 . The device according to claim 7 , wherein the cladding layer comprises nitride, oxynitride, low-k dielectric material, or silicon oxycarbide (SiOC).
13 . A device comprising:
strained silicon (Si) fins on a first portion of a substrate;
Si fins on a second portion of the substrate;
shallow trench isolation (STI) regions between adjacent strained Si fins and Si fins; and
a cladding layer over top and side surfaces of the strained Si fins and the Si fins and over the STI regions in the second portion of the Si substrate.
14 . The device according to claim 13 , wherein the strained Si fins comprise silicon germanium (SiGe).
15 . The device according to claim 14 , wherein a bottom portion of the SiGe fins is oxidized.
16 . The device according to claim 15 , wherein the SiGe fins comprise a first SiGe material over a second SiGe material.
17 . The device according to claim 16 , wherein the first SiGe material has a higher concentration of germanium (Ge) than the second SiGe material.
18 . The device according to claim 17 , wherein the Si fins comprise a Si material over the second SiGe material.
19 . The device according to claim 16 , further comprising a dopant implanted in the substrate under the second SiGe material of the Si fins and under the SiGe fins.
20 . The device according to claim 13 , wherein the cladding layer comprises nitride, oxynitride, low-k dielectric material, or silicon oxycarbide (SiOC).