Semiconductor component and method for fabricating the same
A semiconductor component, which includes a substrate, an interfacial layer disposed on the substrate, a first metal gate structure and a second metal gate structure disposed on the substrate. The first metal gate structure includes a first high-k dielectric layer disposed on the interfacial layer, and a first metal gate layer disposed on the first high-k dielectric layer. The second metal gate structure includes a second high-k dielectric layer disposed on the interfacial layer, a third high-k dielectric layer disposed on the second high-k dielectric layer, and a second metal gate layer disposed on the third high-k dielectric layer.
1. A semiconductor component, comprising:
a substrate;
an interfacial layer disposed on the substrate;
a first metal gate structure disposed on the substrate, comprising:
a first high-k dielectric layer disposed on the interfacial layer;
a first barrier layer in contact with the first high-k dielectric layer; and
a first metal gate layer disposed on the first barrier layer; and
a second metal gate structure disposed on the substrate, comprising:
a second high-k dielectric layer disposed on the interfacial layer;
a third high-k dielectric layer disposed on the second high-k dielectric layer, wherein the second high-k dielectric layer is between the third high-k dielectric layer and the interfacial layer, and the first high-k dielectric layer and the third high-k dielectric layer are made of different materials; and
a second metal gate layer disposed on the third high-k dielectric layer.
2. The semiconductor component of claim 1 , wherein a dielectric constant of the second high-k dielectric layer is greater than a dielectric constant of the third high-k dielectric layer.
3. The semiconductor component of claim 1 , wherein the first high-k dielectric layer and the second high-k dielectric layer are made of the same material.
4. The semiconductor component of claim 1 , further comprising a first work function metal layer disposed on the first barrier layer.
5. The semiconductor component of claim 1 , further comprising a second work function metal layer disposed on the third high-k dielectric layer.
6. The semiconductor component of claim 5 , further comprising a second barrier layer disposed between the third high-k dielectric layer and the second work function metal layer.
7. The semiconductor component of claim 1 , wherein the second metal gate structure comprises a second barrier layer in contact with the third high-k dielectric layer.
8. The semiconductor component of claim 7 , wherein the first barrier layer and the second barrier layer are made of the same material.
9. A semiconductor component, comprising:
a plurality of first devices, each of the plurality of the first devices comprising:
a first source;
a first drain; and
a first metal gate structure disposed between the first source and the first drain, the first metal gate structure comprising:
a first high-k dielectric layer; and
a first metal gate layer disposed on the first high-k dielectric layer; and
a plurality of second devices, each of the plurality of the second devices comprising:
a second source;
a second drain; and
a second metal gate structure disposed between the second source and the second drain, the second metal gate structure comprising:
a second high-k dielectric layer;
a third high-k dielectric layer disposed on the second high-k dielectric layer; and
a second metal gate layer disposed on the third high-k dielectric layer, wherein a number of the plurality of the first devices is greater or less than a number of the plurality of the second devices.
10. The semiconductor component of claim 9 , wherein a threshold voltage of at least one of the plurality of the first devices is different from a threshold voltage of at least one of the plurality of the second devices.
11. The semiconductor component of claim 9 , wherein the plurality of the first devices and the plurality of the second devices are FinFET devices.
12. The semiconductor component of claim 9 , wherein each of the plurality of the first devices further comprises a first work function metal layer disposed between the first high-k dielectric layer and the first metal gate layer.
13. The semiconductor component of claim 9 , wherein each of the plurality of the second devices further comprises a second work function metal layer disposed between the third high-k dielectric layer and the second metal gate layer.
14. The semiconductor component of claim 9 , wherein a material of the first high-k dielectric layer is the same as a material of the second high-k dielectric layer.
15. The semiconductor component of claim 9 , wherein a material of the first high-k dielectric layer is the same as a material of the third high-k dielectric layer.
16. A method for fabricating a semiconductor component, comprising:
forming an interfacial layer on a substrate;
forming a first high-k dielectric layer on the interfacial layer;
forming a second high-k dielectric layer on a first part of the first high-k dielectric layer, wherein the first part of the first high-k dielectric layer is between the second high-k dielectric layer and the interfacial layer;
forming a barrier layer on the second high-k dielectric layer and directly on a second part of the first high-k dielectric layer; and
forming a metal gate layer on the barrier layer.
17. The method of claim 16 , wherein a dielectric constant of the first high-k dielectric layer is greater than a dielectric constant of the second high-k dielectric layer.
18. The method of claim 16 , wherein a dielectric constant of the first high-k dielectric layer is less than a dielectric constant of the second high-k dielectric layer.
19. The method of claim 16 , further comprising forming a work function metal layer between the barrier layer and the metal gate layer.
20. The method of claim 19 , wherein the barrier layer, the work function metal layer, and the metal gate layer form a metal gate structure of a FinFET device.