Semiconductor device and a method for fabricating the same
A semiconductor device includes a source/drain region, a source/drain silicide layer formed on the source/drain region, and a first contact disposed over the source/drain silicide layer. The first contact includes a first metal layer, an upper surface of the first metal layer is at least covered by a silicide layer, and the silicide layer includes a same metal element as the first metal layer.
1. A semiconductor device including a field effect transistor, comprising:
a source/drain region;
a source/drain silicide layer formed on the source/drain region;
a first contact disposed in the interlayer dielectric layer over the source/drain silicide layer; and
a second contact disposed over the first contact, wherein:
the first contact includes a first metal layer,
an upper surface of the first metal layer is partially covered by a silicide layer,
the silicide layer includes a same metal element as the first metal layer,
a bottom of the second contact is in direct contact with the first metal layer and is located above a bottom surface of the silicide layer.
2. The semiconductor device of claim 1 , wherein:
the first contact further includes an adhesive layer, and
the adhesive layer is disposed between the first metal layer and the source/drain silicide layer.
3. The semiconductor device of claim 1 , further comprising a dielectric layer, in which the first contact is embedded,
wherein the silicide layer protrudes above an upper surface of dielectric layer.
4. The semiconductor device of claim 1 , wherein the silicide layer is made of Co silicide and the first metal layer is made of Co.
5. The semiconductor device of claim 1 , further comprising:
a dielectric layer, in which the first contact is embedded; and
an insulating layer in contact with the silicide layer and the dielectric layer,
wherein the insulating layer is made of a different material than the dielectric layer.
6. The semiconductor device of claim 1 , wherein the bottom of the second contact is in contact with the upper surface of the first metal layer.
7. A semiconductor device including a field effect transistor, comprising:
a first interlayer dielectric layer;
a first contact including a first metal layer, embedded in the first interlayer dielectric layer and disposed over an underlying conductive layer;
an adhesive layer disposed between the first contact and the underlying conductive layer;
a first silicide layer partially covering an upper surface of the first metal layer;
an insulating layer disposed over the first interlayer dielectric layer;
a second interlayer dielectric layer disposed over the insulating layer; and
a second contact embedded in the second interlayer dielectric layer and in contact with at least one of the silicide layer and the first contact, wherein:
the silicide layer is made of Co silicide and the first metal layer is made of Co, and
a bottom of the second contact is in contact with the first metal layer.
8. The semiconductor device of claim 7 , wherein the bottom of the second contact is in contact with the upper surface of the first metal layer.
9. The semiconductor device of claim 8 , wherein the insulating layer is in contact with a part of the upper surface of the first metal layer.
10. The semiconductor device of claim 9 , wherein the silicide layer is in contact with the insulating layer.
11. The semiconductor device of claim 9 , wherein the silicide layer is in contact with the adhesive layer.
12. The semiconductor device of claim 7 , wherein the bottom of the second contact is located above a bottom surface of the silicide layer.
13. The semiconductor device of claim 7 , wherein the insulating layer is made of a different material than the first and second interlayer dielectric layers.
14. The semiconductor device of claim 13 , wherein the insulating layer includes at least one selected from the group consisting of SiN, SiC, SiCN and SiON.
15. A semiconductor device including a field effect transistor, comprising:
a first contact disposed over a conductive portion formed over a substrate and embedded in an interlayer dielectric layer;
an adhesive layer disposed between the interlayer dielectric layer and the first contact; and
a second contact disposed over the first contact, wherein:
the first contact includes a first metal layer,
an upper surface of the first metal layer is partially covered by a silicide layer,
the silicide layer includes a same metal element as the first metal layer, and
the bottom of the second contact is in direct contact with and the first metal layer and is located above a bottom surface of the silicide layer.
16. The semiconductor device of claim 15 , wherein a bottom of the second contact is in contact with the first metal layer.
17. The semiconductor device of claim 16 , wherein the bottom of the second contact is located above an upper surface of the silicide layer.
18. The semiconductor device of claim 15 , wherein the adhesive layer includes a TiN layer formed on a Ti layer.
19. The semiconductor device of claim 15 , wherein the adhesive layer is in contact with the silicide layer.
20. The semiconductor device of claim 15 , wherein the silicide layer is made of Co silicide and the first metal layer is made of Co.