Claims
- 1. A process for forming a dielectric layer over a substrate, said process comprising:
coating said substrate with a solution comprising a soluble source of silicon oxide, water, a solvent, a nonionic surfactant, an ionic additive, and an acid catalyst; and treating said coated substrate to harden said solution into a porous silicon oxide film.
- 2. The process of claim 1 wherein said nonionic surfactant is first purified to remove alkali metal impurities.
- 3. The process of claim 1 wherein said nonionic surfactant comprises less than or equal to 50 parts per billion of any alkali metal.
- 4. The process of claim 1 wherein said ionic additive is a compound selected from the group consisting of (a) tetraalkylammonium salts, (b) tetraorganoammonium salts, (c) organoamines in acidic media and combinations thereof.
- 5. The process of claim 1 wherein said ionic additive is a compound chosen from the group consisting of tetraalkylammonium salts and salts with the general cationic composition [NR(CH3)3]+A−, where R is a hydrophobic ligand of chain length 1 to 24, and A− is an anion.
- 6. The process of claim 1 wherein said ionic additive is added to said solution in an amount in the range between 0.1 and 2000 parts per million.
- 7. The process of claim 1 wherein said ionic additive is selected from the group consisting of (a) a tetramethylammonium salt and (b) a salt exhibiting complete decomposition to volatile species upon heating to a temperature between 300 and 450° C., and which leaves no residue.
- 8. The process of claim 1 wherein said ionic additive is a compound chosen from a group of cationic additives of the general composition [NR(CH3)3]+A−, where R is a hydrophobic ligand of chain length 1 to 24, including tetramethylammonium and cetyltrimethylamnmonium, and A− is an anion, which is chosen from the group consisting of formate, nitrate, oxalate, acetate, phosphate, carbonate and hydroxide and combinations thereof.
- 9. The process of claim 1 wherein said ionic additive is a tetramethylammonium salt chosen from a group of compounds consisting of
tetramethylammonium formate, tetramethylammonium nitrate, tetramethylammonium oxalate, tetramethylammonium acetate, tetramethylammonium hydroxide and other salt exhibiting complete decomposition to volatile species upon heating to a temperature between 300 and 450° C. and which leaves no residue.
- 10. The process of claim 1 wherein said solution is formulated by combining at least a first mixture and a second mixture.
- 11. The process of claim 10 wherein said first mixture and said second mixture are combined prior to said coating.
- 12. The process of claim 10 wherein said first mixture comprises a solvent, water, an acid catalyst and the ionic additive, and said second mixture comprises a soluble silicon oxide source a solvent.
- 13. A process for forming a dielectric layer over a substrate, said process comprising:
coating said substrate with a solution comprising a soluble source of silicon oxide, water, a solvent, a nonionic surfactant, an ionic additive, and an acid catalyst; and treating said coated substrate to harden said solution into an porous silicon oxide film, wherein said nonionic surfactant is first purified to remove alkali metal impurities; and wherein said ionic additive is selected from the group consisting of (a) tetraalkylammonium salts, (b) tetraorganoammonium salts, (c) organoamines in acidic media and combinations thereof.
- 14. A process for forming a dielectric layer over a substrate, said process comprising:
coating said substrate with a solution comprising a soluble source of silicon oxide, water, a solvent, a nonionic surfactant, an ionic additive, and an acid catalyst; and treating said coated substrate to harden said solution into a porous silicon oxide film, wherein said nonionic surfactant is first purified to remove alkali metal impurities; and wherein said ionic additive is a tetramethylammonium salt chosen from a group of compounds consisting of tetramethylarnmonium formate, tetramethylammonium nitrate, tetramethylammonium oxalate, tetramethylammonium acetate, tetramethylammonium hydroxide and other salt exhibiting complete decomposition to volatile species upon heating to a temperature between 300 and 450° C. and which leaves no residue.
- 15. A process for forming a dielectric layer over a substrate, said process comprising:
coating said substrate with a solution comprising a soluble source of silicon oxide, water, a solvent, a nonionic surfactant, an ionic additive, and an acid catalyst; and treating said coated substrate to harden said solution into a porous silicon oxide film, wherein said nonionic surfactant is first purified to remove alkali metal impurities; and wherein said ionic additive is a compound chosen from a group of cationic additives of the general composition [NR(CH3)3]+A−, where R is a hydrophobic ligand of chain length 1 to 24, including tetramethylammonium and cetyltrimethylammonium, and A− is an anion, which is chosen from the group consisting of formate, nitrate, oxalate, acetate, phosphate, carbonate, and hydroxide and combinations thereof.
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. provisional application Ser. No. 60/194,356 filed Apr. 4, 2000, which is incorporated herein by reference.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60194356 |
Apr 2000 |
US |
Continuations (1)
|
Number |
Date |
Country |
Parent |
09823932 |
Mar 2001 |
US |
Child |
10219164 |
Aug 2002 |
US |