Claims
- 1. A method of providing a dielectric structure on a substrate, comprising the steps of:
- (a) providing a first layer of a primary dielectric on the substrate, said primary dielectric being a metal oxide having a high dielectric constant selected from the group consisting of Ta.sub.2 O.sub.5, TiO.sub.2, Nb.sub.2 O.sub.5 and Al.sub.2 O.sub.3 ;
- (b) providing a first secondary dielectric layer on said first primary dielectric layer;
- (c) annealing said first primary dielectric layer in an oxygen-bearing ambient:
- (d) providing a second layer of said primary dielectric on said first secondary dielectric layer;
- (e) providing a second layer of said secondary dielectric on said second primary dielectric layer; and
- (f) annealing said second layer of said primary dielectric;
- wherein after said step of annealing each of said layers of said primary dielectric has a polycrystalline structure characterized by mean surface roughness of less than about 5 to 7 Angstroms.
- 2. A method as recited in claim 1, further comprising the step of providing an interface secondary dielectric layer on the substrate and below said first primary dielectric layer.
- 3. A method as recited in claim 1, further comprising the step of forming an oxide layer on said substrate and below said first primary dielectric layer simultaneously with said step (c).
- 4. A method as recited in claim 1, wherein each of said steps of providing a secondary dielectric layer comprises providing a secondary dielectric layer having a thickness between approximately 10 Angstroms and approximately 50 Angstroms.
- 5. A method as recited in claim 1, wherein each of said steps of providing a secondary dielectric layer comprises providing a layer of a substance selected from the group consisting of SiO.sub.2, Si.sub.3 N.sub.4, TiO.sub.2, and Al.sub.2 O.sub.3.
- 6. A method as recited in claim 1, further comprising the step of providing an interface secondary dielectric layer on the substrate and below said first primary dielectric layer.
- 7. A method as recited in claim 1, further comprising the step of forming an oxide layer on said substrate and below said first primary dielectric layer simultaneously with said step (c).
- 8. A method of providing a dielectric structure on a substrate, comprising the steps of:
- (a) providing a first layer of a primary dielectric on the substrate, said primary dielectric being Ta.sub.2 O.sub.5 ;
- (b) providing a first secondary dielectric layer on said first primary dielectric layer;
- (c) annealing said first primary dielectric layer in an oxygen-bearing ambient;
- (d) providing a second layer of said primary dielectric on said first secondary dielectric layer;
- (e) providing a second layer of said secondary dielectric on said second primary dielectric layer; and
- (f) annealing said second layer of said primary dielectric;
- wherein each of said steps of providing a primary dielectric layer comprises forming a layer having a thickness of less than approximately 200 Angstroms.
- 9. A method as recited in claim 1, wherein each of said steps of providing a primary dielectric layer comprises providing a layer having a thickness of less than approximately 100 Angstroms.
- 10. A method of forming a capacitor on a substrate wherein the substrate serves as a first electrode, comprising the steps of:
- (a) providing a first layer of a primary dielectric on the substrate, said primary dielectric being a metal oxide having a high dielectric constant;
- (b) providing a first secondary dielectric layer on said first primary dielectric layer;
- (c) providing a second layer of said primary dielectric on said first secondary dielectric layer;
- (d) providing a second secondary dielectric layer on said second primary dielectric layer;
- (e) annealing each of said primary dielectric layers so that each of said primary dielectric layers has a polycrystalline structure characterized by mean surface roughness of less than about 5 to 7 Angstroms; and
- (f) forming a second electrode on a final layer of said secondary dielectric.
- 11. A method as recited in claim 10, wherein said primary dielectric is selected from the group consisting of Ta.sub.2 O.sub.5, TiO.sub.2, Nb.sub.2 O.sub.5 and Al.sub.2 O.sub.5.
- 12. A method as recited in claim 11, wherein said primary dielectric is Ta.sub.2 O.sub.5, and each of said steps of providing a primary dielectric layer comprises forming a Ta.sub.2 O.sub.5 layer having a thickness of less than approximately 200 Angstroms.
- 13. A method as recited in claim 11, wherein each of said steps of providing a primary dielectric layer comprises forming a Ta.sub.2 O.sub.5 layer having a thickness of less than approximately 100 Angstroms.
- 14. A method as recited in claim 10, wherein each of said steps of providing a secondary dielectric layer comprises providing a secondary dielectric layer having a thickness between approximately 10 Angstroms and approximately 50 Angstroms.
- 15. A method as recited in claim 14, wherein each of said steps of providing a primary dielectric layer comprises forming a Ta.sub.2 O.sub.5 layer having a thickness of less than approximately 100 Angstroms.
- 16. A method as recited in claim 15, wherein each of said steps of annealing comprises the step of annealing in an oxygen bearing ambient.
- 17. A method as recited in claim 10, wherein each of said steps of providing a secondary dielectric layer comprises providing a layer of a substance selected from the group consisting of SiO.sub.2, Si.sub.3 N.sub.4, TiO.sub.2, and Al.sub.2 O.sub.3.
- 18. A method as recited in claim 10, wherein each of said annealed layers of said primary dielectric has a crystalline structure characterized by relatively small grain size.
Parent Case Info
This is a continuation of application Ser. No. 08/088,312 filed on Jul. 7, 1993, now abandoned, which is is a divisional of application Ser. No. 07/907,915 filed on Jul. 2, 1992, now abandoned.
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Entry |
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Divisions (1)
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Number |
Date |
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Parent |
907915 |
Jul 1992 |
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Continuations (1)
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Number |
Date |
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88312 |
Jul 1993 |
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