Integrated metal gate CMOS devices
View Patent ↗A semiconductor device comprises a first semiconductor fin arranged on a substrate, the first semiconductor fin having a first channel region, and a second semiconductor fin arranged on the substrate, the second semiconductor fin having a second channel region. A first gate stack is arranged on the first channel region. The first gate stack comprises a first metal layer arranged on the first channel region, a work function metal layer arranged on the first metal layer, and a work function metal arranged on the work function metal layer. A second gate stack is arranged on the second channel region, the second gate stack comprising a work function metal arranged on the second channel region.
1. A method for forming semiconductor devices, the method comprising:
forming a first channel region, a second channel region, a third channel region, and a fourth channel region on a substrate;
forming a first metal layer on the first channel region, the second channel region, the third channel region, and the fourth channel region;
forming a sacrificial block layer on the first metal layer and forming a sacrificial patterning layer on the sacrificial block layer;
removing the first metal layer, the sacrificial block layer and the sacrificial patterning layer from the first channel region;
forming a barrier metal layer on the first channel region and over a nitride layer along with forming the harrier metal layer on the second channel region, the third channel region, and the fourth channel region;
removing, from the second channel region and the third channel region, the first metal layer, the sacrificial block layer, the sacrificial patterning layer, and the barrier metal layer;
removing, from the fourth channel region, the barrier metal layer, and the sacrificial patterning layer;
removing the sacrificial block layer from the fourth channel region;
depositing a third metal layer and a work function metal layer on the first channel region, the second channel region, the third channel region, and the fourth channel region;
removing the third metal layer and the work function metal layer from the third channel region; and
depositing another work function metal on the first channel region, the second channel region, the third channel region, and the fourth channel region.
2. The method of claim 1 , wherein the first channel region, the second channel region, the third channel region, and the fourth channel region include semiconductor fins.
3. The method of claim 1 , wherein prior to removing the first metal layer, the sacrificial block layer and the sacrificial patterning layer from the first channel region, a mask layer is patterned on the second channel region, the third channel region, and the fourth channel region.
4. The method of claim 1 , further comprising depositing another nitride layer on the work function metal layer.
5. The method of claim 4 , further comprising removing the another nitride layer from the third channel region when removing the third metal layer and the work function metal layer.
6. The method of claim 1 , further comprising depositing a gate conductor material on the first channel region, the second channel region, the third channel region, and the fourth channel region.
7. The method of claim 1 , further comprising forming an interfacial layer on the first channel region, the second channel region, the third channel region, and the fourth channel region prior to forming the first metal layer on the first channel region, the second channel region, the third channel region, and the fourth channel region.
8. The method of claim 1 , further comprising forming a metal capping layer on the first channel region prior to forming the first metal layer on the first channel region.
9. The method of claim 1 , further comprising forming a metal capping layer on the second channel region prior to forming the first metal layer on the second channel region.
10. The method of claim 1 , further comprising forming a metal capping layer on the third channel region prior to forming the first metal layer on the third channel region.
11. The method of claim 1 , further comprising forming a metal capping layer on the fourth channel region prior to forming the first metal layer on the first fourth region.