Capacitor having a barrier layer made of a transition metal phosphide, arsenide or sulfide
View Patent ↗The capacitor has a capacitor dielectric formed, in particular, as a high-□-dielectrical or ferroelectrical layer. A barrier layer is formed of a compound of a transition element with phosphorus, sulfur or arsenic. The barrier layer is underneath the capacitor dielectric. The barrier layer is oxygen-impermeable and thus prevents the oxidation of deep structures during high-temperature processes, in particular during the production of the capacitor dielectric.
1. A capacitor in an integrated semiconductor circuit, comprising:
a semiconductor substrate having a doped region formed therein;
a first electrode connected to said doped region;
a second electrode;
a capacitor dielectric insulating said first electrode from said second electrode; and
a barrier layer disposed below said capacitor dielectric, said barrier layer consisting essentially of a compound formed from a transition element and a material selected from the group consisting of phosphorus, sulfur, and arsenic.
2. The capacitor according to claim 1 , wherein said first electrode is directly connected to said doped region.
3. The capacitor according to claim 1 , which further comprises a connection structure connecting said first electrode to said doped region.
4. The capacitor according to claim 1 , wherein said barrier layer is disposed directly underneath said capacitor dielectric and covers an entire interface between said first electrode and said capacitor dielectric.
5. The capacitor according to claim 3 , wherein said barrier layer is disposed underneath said first electrode and covers an entire interface between said first electrode and said connection structure.
6. The capacitor according to claim 1 , wherein said barrier layer is disposed underneath said first electrode and covers an entire interface between said first electrode and said doped region.
7. The capacitor according to claim 1 , wherein said capacitor dielectric consists of a material selected from the group consisting of dielectric material and ferroelectric material, and has a value of □>100.
8. The capacitor according to claim 1 , wherein said capacitor dielectric consists of a material selected from the group consisting of BST, SBT, PZT, and PLT.
9. The capacitor according to claim 1 , wherein said first electrode consists of a material selected from the group consisting of Pt-containing material, Ru-containing material, Rh-containing material, and Ir-containing material.
10. The capacitor according to claim 3 , wherein said connection structure is made of a material selected from the group consisting of polysilicon and tungsten.
11. The capacitor according to claim 1 , wherein said barrier layer is essentially a layer selected from the group consisting of a tungsten phosphide layer, a tantalum phosphide layer, and a hafnium phosphide layer.
12. A semiconductor configuration, comprising a capacitor according to claim 1 , and an associated selection transistor which encompasses said doped region.