Method of manufacturing semiconductor devices and semiconductor devices
View Patent ↗A gate structure of a field effect transistor includes a first gate dielectric layer, a second gate dielectric layer, and one or more conductive layers disposed over the first gate dielectric layer and the second gate dielectric layer. The first gate dielectric layer is separated from the second gate dielectric layer by a gap filled with a diffusion blocking layer.
1. A method of manufacturing a semiconductor device, comprising:
forming a gate dielectric layer in a gate space, the gate space being laterally surrounded by one or more insulating layers;
separating the gate dielectric layer into a first gate dielectric layer and a second gate dielectric layer by forming a trench;
forming one or more work function adjustment material (WFM) layers over the first gate dielectric layer and the second gate dielectric layer; and
forming a body gate electrode layer over the one or more WFM layers.
2. The method of claim 1 , wherein:
the gate dielectric layer comprises a first region and a second region adjacent to the first region,
at least one of the first region or the second region includes a dopant,
a dopant concentration is different in the first region than the second region, and
the first gate dielectric layer includes the first region and the second gate dielectric layer includes the second region.
3. The method of claim 2 , wherein the dopant is at least one selected from the group consisting of La, Sc, Sr, Ce, Y, Dy, Eu, Pb, Tr, Nd, Gd, Pm, Pr, Ho, Er, Tm, Sm, Yb, Al, Nb, Mo, W, Ti, Hf, Zr, Ta, V, Ba and Mg.
4. The method of claim 2 , wherein the gate dielectric layer includes one selected from the group consisting of hafnium oxide, zirconium oxide and hafnium-zirconium oxide.
5. The method of claim 1 , wherein the trench is filled by a part of the one or more WFM layers.
6. The method of claim 1 , wherein the separating the gate dielectric layer comprises:
forming a hard mask layer over the gate dielectric layer;
forming a mask pattern having an opening over the hard mask layer;
patterning the hard mask layer by using the mask pattern as an etching mask;
patterning the gate dielectric layer by using at least one of the mask pattern or the patterned hard mask layer as an etching mask; and
removing the mask pattern and the patterned hard mask layer.
7. The method of claim 6 , wherein the hard mask layer is made of a different material than the gate dielectric layer and includes at least one selected from the group consisting of aluminum oxide, aluminum nitride, aluminum oxynitride, titanium oxide, titanium oxynitride, titanium nitride, and tantalum oxynitride.
8. The method of claim 7 , wherein a thickness of the hard mask layer is in a range from 0.5 nm to 20 nm.
9. The method of claim 6 , wherein the mask pattern is made of an organic antireflective coating material.
10. A method of manufacturing a semiconductor device, comprising:
forming a first gate dielectric layer over a first channel region made of a first semiconductor material and over an isolation insulating layer;
forming a second gate dielectric layer over a second channel region made of a second semiconductor material and over the isolation insulating layer, the first gate dielectric layer being laterally in contact with the second gate dielectric layer at a boundary located over the isolation insulating layer;
separating, by using a patterning operation, the first gate dielectric layer and the second gate dielectric layer by a trench; and
forming a diffusion barrier by filling the trench with a dielectric material or a conductive material, wherein:
at least one of the first gate dielectric layer or the second gate dielectric layer includes a dopant,
a dopant concentration is different between the first gate dielectric layer and the second gate dielectric layer, and
the diffusion barrier functions as a barrier for the dopant.
11. The method of claim 10 , wherein the first and second gate dielectric layers includes hafnium oxide.
12. The method of claim 11 , wherein the dopant is at least one selected from the group consisting of La, Sc, Sr, Ce, Y, Dy, Eu and Yb.
13. The method of claim 10 , wherein the separating the first gate dielectric layer and the second gate dielectric layer comprises:
forming a hard mask layer over the first and second gate dielectric layers;
forming a mask pattern having an opening over the hard mask layer and above the boundary;
patterning the hard mask layer by using the mask pattern as an etching mask;
patterning the first and second gate dielectric layers by using at least one of the mask pattern or the patterned hard mask layer as an etching mask; and
removing the mask pattern and the patterned hard mask layer.
14. The method of claim 13 , wherein the hard mask layer includes an aluminum compound.
15. The method of claim 14 , wherein a width of the trench is in a range from 10 nm to 150 nm.
16. The method of claim 10 , wherein the diffusion barrier includes at least one layer of TiAl, TiAlC, TaAl, TaAlC, TiN, TiSiN, Ru, WN, WCN, MoN or TaN.
17. A method of manufacturing a semiconductor device, comprising:
forming a pair of first gate spaces and a pair of second gate spaces;
forming a first gate dielectric layer in the pair of first gate spaces and a second gate dielectric layer in the pair of second gate spaces;
separating, by using a patterning operation, the first gate dielectric layer and the second gate dielectric layer by a trench that connects the pair of first gate spaces and the pair of second gate spaces; and
forming one or more work function adjustment material (WFM) layers over the first gate dielectric layer in the pair of first gate spaces and over the second gate dielectric layer in the pair of second gate spaces; and
forming a body gate electrode layer over the one or more WFM layers,
wherein a part of the one or more WFM layers fills the trench.
18. The method of claim 17 , wherein:
at least one of the first gate dielectric layer or the second gate dielectric layer includes a dopant, and
a dopant concentration is different between the first gate dielectric layer and the second gate dielectric layer.
19. The method of claim 18 wherein the dopant is at least one selected from the group consisting of La, Sc, Sr, Ce, Y, Dy, Eu and Yb.
20. The method of claim 17 , wherein the first and second dielectric layers each includes one selected from the group consisting of one or more of aluminum oxide, aluminum nitride, aluminum oxynitride, titanium oxide and titanium oxynitride.