MIM capacitor high-k dielectric for increased capacitance density
According to one embodiment of the invention, a method for fabricating a MIM capacitor in a semiconductor die includes a step of depositing a first interconnect metal layer. The method further includes depositing a high-k dielectric layer comprising AlN X (aluminum nitride) on the first interconnect layer. The method further includes depositing a layer of MIM capacitor metal on the high-k dielectric layer. The method further includes etching the layer of MIM capacitor metal to form an upper electrode of the MIM capacitor. According to this exemplary embodiment, the first interconnect metal layer, the high-k dielectric layer, and the layer of MIM capacitor metal can be deposited in a PVD process chamber. The method further includes etching the high-k dielectric layer to form a MIM capacitor dielectric segment and etching the first interconnect metal layer to form a lower electrode of the MIM capacitor.
1. A MIM capacitor in a semiconductor die, said MIM capacitor comprising:
a first electrode situated in a first interconnect metal layer;
a dielectric segment comprising AlN X and situated on said first electrode;
a second electrode situated on said dielectric segment and in an interlayer dielectric layer.
2. The MIM capacitor of claim 1 wherein said dielectric segment is selected from the group consisting of AlN and AlN 2 .
3. The MIM capacitor of claim 1 wherein said dielectric segment is deposited using a physical vapor deposition (PVD) process to have a high degree of uniformity.
4. The MIM capacitor of claim 1 wherein said dielectric segment has a thickness of between approximately 200.0 Angstroms and approximately 350.0 Angstroms.
5. The MIM capacitor of claim 1 wherein an interlayer dielectric is situated over said second electrode.
6. The MIM capacitor of claim 5 wherein a metal segment in a second interconnect metal layer is situated on said interlayer dielectric.
7. The MIM capacitor of claim 6 wherein said metal segment is connected to said second electrode by at least one via.
8. The MIM capacitor of claim 1 wherein said dielectric segment has a dielectric constant of at least 10.0.
9. The MIM capacitor of claim 5 wherein said interlayer dielectric comprises a low-k dielectric.
10. The MIM capacitor of claim 1 wherein said second electrode comprises a layer of aluminum and a layer of titanium nitride.
11. The MIM capacitor of claim 1 wherein said second electrode comprises a layer of aluminum situated between layers of titanium nitride.