Forming a semiconductor device having a metal electrode and structure thereof
View Patent ↗A method for forming a semiconductor device includes forming a gate dielectric over a substrate, forming a metal electrode over the gate dielectric, forming a first sacrificial layer which includes polysilicon or a metal over the metal electrode, removing the first sacrificial layer, and forming a gate electrode contact over and coupled to the metal electrode.
1. A method for forming a semiconductor device comprising:
forming a gate dielectric over a substrate;
forming a metal electrode over the gate dielectric;
forming a first sacrificial layer over the metal electrode, wherein the first sacrificial layer comprises a material selected from a group consisting of polysilicon and a metal;
removing the first sacrificial layer; and
forming a gate electrode contact over and coupled to the metal electrode.
2. The method of claim 1 , further comprising:
forming a spacer adjacent the metal electrode and the first sacrificial layer, wherein forming the spacer is performed prior to removing the first sacrificial layer.
3. The method of claim 1 , wherein forming the first sacrificial layer comprises forming the first sacrificial layer comprising polysilicon.
4. The method of claim 1 , wherein forming the first sacrificial layer comprises forming the first sacrificial layer comprising a first metal.
5. The method of claim 4 , wherein forming the first sacrificial layer comprising the first metal comprises:
forming the first sacrificial layer comprising the first metal, wherein the first sacrificial layer is capable of being removed selective to the metal electrode.
6. The method of claim 4 , wherein forming the metal electrode comprises forming the metal electrode comprising a second metal, different from the first metal.
7. The method of claim 1 , wherein forming the metal electrode comprises forming the metal electrode having a thickness in a range of approximately 20 to approximately 200 Angstroms, and forming the first sacrificial layer comprises forming the first sacrificial layer having a thickness in a range of approximately 400 to approximately 1000 Angstroms.
8. The method of claim 1 , further comprising:
forming a second sacrificial layer over the first sacrificial layer; and
removing the second sacrificial layer prior to forming the gate electrode contact.
9. The method of claim 8 , wherein forming the second sacrificial layer comprises forming the second sacrificial layer comprising nitride.
10. The method of claim 8 , wherein forming the second sacrificial layer comprises forming the second sacrificial layer comprising a metal.
11. A method for forming a semiconductor device comprising:
forming a gate dielectric over a substrate;
forming a metal electrode over the gate dielectric;
forming a first sacrificial layer over the metal electrode, the first sacrificial layer comprising polysilicon;
forming a second sacrificial layer over the first sacrificial layer;
forming a spacer adjacent the metal electrode, the first sacrificial layer, and the second sacrificial layer;
removing the second sacrificial layer;
removing the first sacrificial layer; and
forming a gate electrode contact over and coupled to the metal electrode.
12. The method of claim 11 , wherein forming the second sacrificial layer comprises forming the second sacrificial layer comprising nitride.
13. The method of claim 11 , wherein forming the second sacrificial layer comprises forming the second sacrificial layer comprising a metal.
14. The method of claim 11 , wherein forming the spacer comprises forming the spacer having a height that is at least twice a combined height of the metal electrode and the gate dielectric.
15. The method of claim 11 , wherein forming the metal electrode comprises forming the metal electrode having a thickness in a range of approximately 20 to approximately 200 Angstroms.
16. The method of claim 11 , wherein forming the first sacrificial layer comprises forming the first sacrificial layer having a thickness in a range of approximately 400 to approximately 1000 Angstroms.
17. The method of claim 11 , wherein forming the second sacrificial layer comprises forming the second sacrificial layer having a thickness in a range of approximately 50 to approximately 400 Angstroms.
18. The method of claim 11 , further comprising:
forming source/drain regions in the substrate adjacent and underlying at least a portion of the gate dielectric prior to removing the first sacrificial layer and prior to removing the second sacrificial layer.