Ferroelectric rare-earth manganese-titanium oxides
View Patent ↗Ferroelectric rare-earth manganese-titanium oxides and methods of their manufacture. The ferroelectric materials can provide nonvolatile data storage in rapid access memory devices.
1. A composition comprising:
a ferroelectric material having the formula (Y 1-x A x )(Mn 1-y B y )O 3 ;
wherein A comprises a metal having a valence of 3, and 0<x<1; and,
B comprises Ti, and 0<y<1.
2. The composition of claim 1 , wherein A comprises a rare-earth metal.
3. The composition of claim 1 , wherein y ranges from about 0.005 to about 1.0.
4. The composition of claim 3 , wherein y ranges from about 0.35 to about 0.65.
5. The composition of claim 1 , wherein the ferroelectric material further comprises a remnant polarization (Pr) of greater than 1 uC/cm2.
6. The composition of claim 1 , wherein the ferroelectric material further comprises a dielectric constant greater than 1.
7. The composition of claim 6 , wherein the dielectric constant ranges from about 5 to about 20.
8. The composition of claim 1 , further comprising a substrate.
9. The composition of claim 8 , wherein the substrate comprises a material selected from the group consisting of: Si, Ge, GaAs, GaN, Al2O3, SiC and AlN.
10. The composition of claim 1 , wherein the composition is incorporated into an FeRAM, a nonvolatile memory, a ferroelectric-gate FET or a MFIS.
11. A composition comprising:
a ferroelectric material having the formula (Y 1-x A x )(Mn 1-y B y )O 3 ;
wherein A comprises a metal selected from the group consisting of: Sc, Bi, Ce, Yb, Er, and Lu, and 0<x<1; and,
B comprises a metal having a valence of 4 or 3, and 0<y<1.
12. A composition comprising:
a ferroelectric material having the formula (Y 1-x A x )(Mn 1-y B y )O 3 ;
wherein A comprises a metal having a valence of 3, and 0<x<1; and,
B comprises a metal having a valence of 4 or 3, and 0<y<1;
wherein the ferroelectric material is in the form of a thin film layer with a thickness between about 500 angstroms (Å) and 3000 Å.
13. A composition comprising:
a ferroelectric material having the formula (Y 1-x A x )(Mn 1-y B y )O 3 ;
wherein A comprises a metal having a valence of 3, and 0<x<1;
B comprises a metal having a valence of 4 or 3, and 0<y<1; and,
further comprising an electrode between the substrate and the ferroelectric material.
14. The composition of claim 13 , wherein the electrode comprises a material selected from the group consisting of: Pt, Au, Al and Ru.