US5624707A
Expired / Lapsed
US
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Method of forming ABO3 films with excess B-site modifiers
Assignee: Panasonic Holdings Corp
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Filing: 1994-07-05
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Granted: 1997-04-29
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Expires: 2014-07-05
Abstract
Abstract A method for fabricating an integrated circuit capacitor having a dielectric layer comprising BST with excess B-site material, such as titanium, added. A polyoxyalkyated metal liquid precursor solution is prepared comprising a stock solution of BST of greater then 99.999% purity blended with excess B-site material such as titanium such that the titanium is in the range of 0-100 mol %. A xylene exchange is then performed to adjust the viscosiy of the solution for spin-on application to a substrate. The precursor is spun on a first electrode, dried at 400 DEG C. for 2 minutes, then annealed at 650 DEG C. to 800 DEG C. for about an hour to form a layer of BST with excess titanium. A second electrode is deposited, patterned, and annealed at between 650 DEG C. to 800 DEG C. for about 30 minutes. The resultant capacitor exhibits an enlarged dielectric constant with only a small increase in leakage current.
Inventors
- 👤 Masamichi Azuma
- 👤 Carlos A. Paz de Araujo
- 👤 Michael C. Scott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:10
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/60; H10P14/69; H10P14/692; H10P14/6938; H10P14/69398; C; C04; C04B; C04B35/00; C04B35/01; C04B35/46; C04B35/462; C04B35/465; C04B35/468; C04B35/4682; C04B35/47; C04B35/622; C04B35/626; C04B35/62605; C04B35/62625; C04B35/6264; C23; C23C; C23C16/00; C23C16/44; C23C16/4412; C23C16/448; C23C16/4486; C23C16/455; C23C16/45561; C23C16/45563; C23C16/4558; C23C16/46; C23C16/48; C23C16/482; C23C16/52; C23C18/00; C23C18/02; C23C18/12; C23C18/1204; C23C18/1208; C23C18/1216; C23C18/125; C23C18/1275; C23C18/1295; C30; C30B; C30B29/00; C30B29/60; C30B29/68; C30B7/00; H01; H01C; H01C7/00; H01C7/10; H01C7/1013; H10B; H10B12/00; H10B12/30; H10B53/00; H10D; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10D1/684; H10D1/692; H10P14/66; H10P14/668; C04B2235/00; C04B2235/02; C04B2235/30; C04B2235/32; C04B2235/3201; C04B2235/3203; C04B2235/3205; C04B2235/3206; C04B2235/3208; C04B2235/3213; C04B2235/3217; C04B2235/3224; C04B2235/3227; C04B2235/3229; C04B2235/3231; C04B2235/3232; C04B2235/3234; C04B2235/3241; C04B2235/3243; C04B2235/3251; C04B2235/3262; C04B2235/3268; C04B2235/327; C04B2235/3272; C04B2235/3275; C04B2235/3279; C04B2235/3281; C04B2235/3284; C04B2235/3289; C04B2235/44; C04B2235/441; C04B2235/449; C04B2235/65; C04B2235/658; C04B2235/6583; C04B2235/6585; C04B2235/70; C04B2235/72; C04B2235/74; C04B2235/79; H10P14/63; H10P14/6326; H10P14/6342; H10P14/65; H10P14/6502; H10P14/6506
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
172 words
A method for fabricating an integrated circuit containing a barium strontium titanate layer with excess B-site material in addition to a stoichiometric amount of B-site material required to satisfy a formula ABO 3 wherein A is an A-site material, B is a B-site material, and O is oxygen, said method comprising the steps of: providing a liquid precursor comprising barium, strontium, and titanium; blending a stoichiometric excess amount of AB0 3 B-site material into said liquid precursor to form a solution, said stoichiometric excess amount of ABO 3 material ranging from 0.01 mole percent to 100 mole percent of the total amount of B-site material required to satisfy the formula ABO 3 , said liquid precursor and said excess amount of ABO 3 B-site material including a metal-organic complex; applying said solution to an integrated circuit substrate; treating said solution to form said barium strontium titanate layer including said excess amount of B-site material on said substrate; and forming an integrated circuit that includes said barium strontium titanate layer on said substrate.
Claim 2
Independent Claim
172 words
A method for fabricating an integrated circuit containing a barium strontium titanate layer with excess B-site material in addition to a stoichiometric amount of B-site material required to satisfy a formula ABO 3 wherein A is an A-site material, B is a B-site material, and O is oxygen, said method comprising the steps of: providing a liquid precursor comprising barium, strontium, and titanium; blending a stoichiometric excess amount of AB0 3 B-site material into said liquid precursor to form a solution, said stoichiometric excess amount of ABO 3 material ranging from 0.01 mole percent to 100 mole percent of the total amount of B-site material required to satisfy the formula ABO 3 , said liquid precursor and said excess amount of ABO 3 B-site material including a metal-organic complex; applying said solution to an integrated circuit substrate; treating said solution to form said barium strontium titanate layer including said excess amount of B-site material on said substrate; and forming an integrated circuit that includes said barium strontium titanate layer on said substrate.
Claim 3
Dependent Claim
30 words
The method of claim 1 including said metal-organic complex selected from the group consisting of barium alkoxides, strontium alkoxides, titanium alkoxides, barium carboxylates, strontium carboxylates, titanium carboxylates, and mixtures thereof.
Claim 4
Dependent Claim
24 words
The method of claim 1 including said metal-organic complex selected from the group consisting of barium 2-ethylhexanoate, strontium 2-ethylhexanoate, titanium isopropoxide, and mixtures thereof.
Claim 5
Dependent Claim
24 words
The method of claim 1 including said metal-organic complex selected from the group consisting of barium 2-ethylhexanoate, strontium 2-ethylhexanoate, titanium 2-ethylhexanoate, and mixtures thereof.
Claim 6
Dependent Claim
24 words
The method of claim 1 including said metal-organic complex selected from the group consisting of barium neodecanoate, strontium neodecanoate, titanium isopropoxide, and mixtures thereof.
Claim 7
Dependent Claim
24 words
The method of claim 1 including said metal-organic complex selected from the group consisting of barium neodecanoate, strontium neodecanoate, titanium neodecanoate, and mixtures thereof.
Claim 8
Dependent Claim
24 words
The method of claim 1 including said metal-organic complex selected from the group consisting of barium octanoate, strontium octanoate, titanium octanoate, and mixtures thereof.
Claim 9
Dependent Claim
25 words
The method of claim 1 wherein said barium, said strontium, and said titanium have less than 10 parts per million of any single impurity element.
Claim 10
Dependent Claim
37 words
The method of claim 1 wherein said step of treating comprises drying said solution at a temperature of from about 100° C. to 500° C. in an atmosphere selected from the group consisting of air and nitrogen.
Claim 11
Dependent Claim
12 words
The method of claim 9 wherein said temperature is approximately 400° C.
Claim 12
Dependent Claim
22 words
The method of claim 1 wherein said step of treating comprises annealing at a temperature of between 700° C. and 850° C.
Claim 13
Dependent Claim
18 words
The method of claim 1 wherein said step of treating comprises annealing at a temperature of 750° C.
Claim 14
Dependent Claim
18 words
The method of claim 1 wherein said step of treating comprises annealing at a temperature of 800° C.
Claim 15
Dependent Claim
32 words
The method of claim 1 wherein said step of providing comprises providing a precursor in a first solvent and performing a solvent exchange to substitute a second solvent for said first solvent.
Claim 16
Dependent Claim
22 words
The method of claim 14 wherein said second solvent comprises a solvent selected from the group consisting of xylene and n-butyl acetate.
Claim 17
Dependent Claim
11 words
The method of claim 15 wherein said first solvent is 2-methoxyethanol.
Claim 18
Dependent Claim
49 words
The method of claim 14 wherein said providing step includes a step of storing said precursor in said first solvent prior to said step of performing said solvent exchange, and wherein said second solvent provides a precursor that has a lesser viscosity than said precursor with said first solvent.
References Cited (Backward Citations)
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