Semiconductor device including dual trench epitaxial dual-liner contacts
A complementary metal-oxide-semiconductor field-effect transistor (CMOS) device includes a first source/drain (S/D) region and a second S/D region different from the first S/D region. A first epitaxy film formed of a first semiconductor material is on the first S/D region. A second epitaxy film formed of a second semiconductor material is on the second S/D region. The CMOS device further includes first and second S/D contact stacks. The first S/D contact stack includes a first contact trench liner having a first inner side wall extending from a first base portion to an upper surface of the first S/D contact stack. The second S/D contact stack includes a second contact trench liner having a second inner side wall extending from a second base portion to an upper surface of the second S/D contact stack. The first inner sidewall directly contacts the second inner sidewall.
1. A method of forming contact trench liners in a complementary metal-oxide-semiconductor field-effect transistor (CMOS) device, the method comprising:
forming a first contact trench over a first source/drain (S/D) region of an n-type transistor (NFET);
forming a second contact trench over a second S/D region of a p-type transistor (PFET);
forming a first epi film in both the first contact trench and the second contact trench and on both the first S/D region and the second S/D region;
replacing the first epi film with a different second epi film in the first contact trench and on the first S/D region;
depositing a first contact trench liner of the contact trench liners comprising a first liner material in the first contact trench without depositing the first contact trench liner in the second contact trench, and depositing a first S/D conductive contact material on the first contact trench liner and in the first contact trench; and
after depositing the first contact trench liner, depositing a second contact trench liner of the contact trench liners comprising a second liner material in the second contact trench, and depositing a second S/D conductive contact material on the second contact trench liner and in the second contact trench,
wherein the second liner material is different from the first liner material;
wherein the first contact trench liner is deposited directly on and physically contacting an upper surface of the different second epi film located in the first contact trench, and the second contact trench liner is deposited directly on and physically contacting an upper surface of a remaining portion of the first epi film located in the second contact trench.
2. The method of claim 1 , further comprising:
filling the first contact trench and the second contact trench with a sacrificial material on the first epi film;
depositing a mask layer atop the sacrificial material;
removing a first portion of the mask layer to expose the sacrificial material filling the first contact trench while maintaining a second portion of the mask layer to cover the sacrificial layer filling the second contact trench;
removing the exposed sacrificial material to form the first contact trench; and
depositing the first contact trench liner in the first contact trench while the second portion of the mask layer covers the sacrificial layer filling the second contact trench.
3. The method of claim 2 , wherein depositing the second contact trench liner comprises:
using the first S/D conductive contact material as a hardmask while removing the sacrificial material from the second contact trench; and
depositing the second contact trench liner in the second contact trench while the first S/D conductive contact material prevents depositing the second contact trench liner in the first contact trench.
4. The method of claim 2 , wherein the sacrificial material comprises amorphous carbon.
5. The method of claim 2 , wherein the sacrificial material comprises at least one of silicon dioxide, aluminum oxide, and silicon nitride.
6. The method of claim 1 , wherein the first liner material comprises titanium (Ti).
7. The method of claim 6 , wherein the second liner material comprises nickel platinum (NiPt).
8. The method of claim 7 , wherein the first S/D conductive contact material and the second S/D conductive contact material each comprise tungsten (W).
9. A method of forming source/drain (S/D) contact stacks in a complementary metal-oxide-semiconductor field-effect transistor (CMOS) device, the method comprising:
forming a first contact trench over a first source/drain (S/D) region of a first transistor;
forming a second contact trench over a second S/D region of a second transistor;
forming a first epi film in both the first contact trench and the second contact trench and on both the first S/D region and the second S/D region;
replacing the first epi film with a different second epi film in the first contact trench and on the first S/D region;
forming a first S/D contact stack of the S/D contact stacks including a first contact trench liner in the first contact trench without forming the first contact trench liner in the second contact trench; and
using the first S/D contact stack as a mask while forming a second S/D contact stack of the S/D contact stacks including a second contact trench liner in the second contact trench such that the second contact trench liner is blocked from depositing in the first contact trench,
wherein the first contact trench liner comprises a first liner material, and the second contact trench liner comprises a second liner material different from the first liner material,
wherein the first contact trench liner is formed directly on and physically contacting an upper surface of the different second epi film located in the first contact trench, and the second contact trench liner is formed directly on and physically contacting an upper surface of a remaining portion of the first epi film located in the second contact trench.
10. The method of claim 9 , further comprising:
filling the first contact trench and the second contact trench with a sacrificial material on the first epi film;
depositing a mask layer atop the sacrificial material;
removing a first portion of the mask layer to expose the sacrificial material filling the first contact trench while maintaining a second portion of the mask layer to cover the sacrificial layer filling the second contact trench;
removing the exposed sacrificial material to form the first contact trench;
depositing the first contact trench liner in the first contact trench while the second portion of the mask layer covers the sacrificial layer filling the second contact trench; and
filling the first contact trench with a first S/D conductive contact material to form the first S/D contact stack.
11. The method of claim 10 , further comprising:
using the first S/D contact stack as a hardmask while removing remaining sacrificial material to form the second contact trench;
depositing the second contact trench liner in the second contact trench while the first S/D contact stack prevents depositing the second contact trench liner in the first contact trench; and
filling the second contact trench with a second S/D conductive contact material to form the second S/D contact stack.
12. The method of claim 11 , wherein the sacrificial material comprises amorphous carbon.
13. The method of claim 11 , wherein the sacrificial material comprises a dielectric material comprising at least one of silicon dioxide, aluminum oxide and silicon nitride.
14. The method of claim 11 , wherein the first liner material comprises titanium (Ti).
15. The method of claim 14 , wherein the second liner material comprises nickel platinum (NiPt).
16. The method of claim 15 , wherein the first transistor comprises an n-type transistor (NFET) and the second transistor comprises a p-type transistor (PFET).
17. The method of claim 16 , wherein the first S/D conductive contact material and the second S/D conductive contact material each comprise tungsten (W).