Capacitors, dielectric structures, and methods of forming dielectric structures
Some embodiments include dielectric structures. The structures include first and second portions that are directly against one another. The first portion may contain a homogeneous mixture of a first phase and a second phase. The first phase may have a dielectric constant of greater than or equal to 25, and the second phase may have a dielectric constant of less than or equal to 20. The second portion may be entirely a single composition having a dielectric constant of greater than or equal to 25. Some embodiments include electrical components, such as capacitors and transistors, containing dielectric structures of the type described above. Some embodiments include methods of forming dielectric structures, and some embodiments include methods of forming electrical components.
1. A method of forming a dielectric structure, comprising:
forming a first portion of the dielectric structure; the first portion comprising a homogeneous mixture of two oxides; one of said two oxides of the mixture of the first portion having a dielectric constant of greater than or equal to 25, and the other of said two oxides of the mixture of the first portion having a dielectric constant of less than or equal to 20;
forming a second portion of the dielectric structure over and directly against the first portion; the second portion consisting of a composition having a dielectric constant of greater than or equal to 25;
forming a third portion of the dielectric structure over and directly against the second portion; the third portion comprising a homogeneous mixture of two oxides; one of said two oxides of the mixture of the third portion having a dielectric constant of greater than or equal to 25, and the other of said two oxides of the mixture of the third portion having a dielectric constant of less than or equal to 20;
wherein the first and third portions are more amorphous than the second portion; and
wherein the first and third portions are different in composition from one another.
2. The method of claim 1 wherein the composition of the second portion is selected from the group consisting of ZrO, HfO, TaO, TiO and SrTiO; where the chemical formulas indicate the elements contained in the composition and do not imply any particular stoichiometry of such elements.
3. The method of claim 1 wherein the first and third portions consist of mixtures selected from the group consisting of ZrAlO, HfAlO, ZrSiO, HfSiO, ZrHfO, ZrTaO, HfTaO, ZrTiO, HfTiO, TaTiO, HfTaTiO and ZrTaTiO; where the chemical formulas indicate the elements contained in the mixture and do not imply any particular stoichiometry of such elements.
4. A capacitor, comprising:
a first capacitor electrode;
a second capacitor electrode; and
a dielectric material between the first and second capacitor electrodes; the dielectric material comprising:
a first portion directly against the first capacitor electrode; the first portion comprising a homogeneous mixture of two oxides; one of said two oxides having a dielectric constant of greater than or equal to 25, and the other of said two oxides having a dielectric constant of less than or equal to 20;
a second portion directly against the first portion; the second portion consisting of a composition having a dielectric constant of greater than or equal to 25, the second portion being more crystalline than the first portion;
a third portion of the dielectric material directly against the second portion of the dielectric material; the third portion of the dielectric material comprising a homogeneous mixture of two oxides with one of said two oxides of the third portion having a dielectric constant of greater than or equal to 25, and the other of said two oxides of the third portion having a dielectric constant of less than or equal to 20, the third portion being less crystalline than the second portion; the third portion of the dielectric material being directly against the second capacitor electrode;
wherein the composition of the second portion is selected from the group consisting of HfO, TaO, TiO and SrTiO; where the chemical formulas indicate the elements contained in the composition and do not imply any particular stoichiometry of such elements;
wherein the first portion consists of a mixture selected from the group consisting of HfAlO, ZrSiO, HfSiO, ZrHfO, ZrTaO, HfTaO, ZrTiO, HfTiO, TaTiO, HfTaTiO and ZrTaTiO; where the chemical formulas indicate the elements contained in the mixture and do not imply any particular stoichiometry of such elements; and
wherein the first and third portions are different in composition from one another.