Titanium silicate films with high dielectric constant

1. In a method of making a capacitor in an integrated device, wherein said capacitor includes a dielectric film with a high dielectric constant, the improvement wherein said dielectric film is made by a sol-gel process, said dielectric film has a composition (SiO 2 ) x (TiO 2 ) 1−x , where 0.50<x<0.75, said dielectric film is applied to a substrate using a spin-on technique, and the resulting film is annealed in an oxygen-containing atmosphere.

2. A method as claimed in claim 1 , wherein the resulting film is annealed at a temperature lying in the range of about 500° C. to 700° C.

3. A method as claimed in claim 2 , wherein said spin-on sol-gel process uses as precursors for said film tetrabutyloxytitanium (TBOT) and tetramethoxysilane (TEOS).

4. A method as claimed in claim 3 , wherein said precursors are diluted with C 2 H 5 OH.

5. A method as claimed in claim 4 , wherein said sol-gel process is carried out in the presence of an acid.

6. A method as claimed in claim 5 , wherein said sol-gel process has aging time of between about 70 and 100 hours.

7. A method as claimed in claim 6 , wherein said annealing temperature is about 600° C.

8. In a method of making a capacitor in an integrated device, wherein said capacitor includes a dielectric film with a high dielectric constant, the improvement wherein said dielectric film is a titanium silicate film, and wherein said dielectric film is made by:

mixing precursors for said titanium silicate film to create a sol, said precursors being selected to form titanium silicate having a composition (SiO 2 ) x (TiO 2 ) 1−x , where 0.50<x<0.75;

forming a gel from said sol;

applying said gel to a substrate using a spin-on technique to form a coating;

drying said coating to form said titanium silicate film; and

annealing said titanium silicate film in an oxygen-containing atmosphere.

9. A method as claimed in claim 8 , wherein said titanium silicate film is annealed at a temperature lying in the range of about 500° C. to 700° C.

10. A method as claimed in claim 9 , wherein said precursors are tetrabutyloxytitanium (TBOT) and tetramethoxysilane (TESO).

11. A method as claimed in claim 10 , wherein said sol is diluted with C 2 H 5 OH to control viscosity.

12. A method as claim 10 , wherein prior to mixing said precursors, said tetramethoxysilane is mixed with an organic solvent and a gel promoter.

13. A method as claimed in claim 12 , wherein the gel promoter is an acid.

14. A method as claimed in claim 13 , wherein said acid is HCl.

15. A method as claimed in claim 12 , wherein said sol is allowed to age for a time sufficient to form said gel, and said aging time is controlled to select the desired characteristics in the resulting titanium silicate film.

16. A method as claimed in claim 15 , wherein said gel promoter is an acid and said aging time is between about 70 and 100 hours.

17. A method as claimed in claim 8 , wherein said titanium silicate film provides a dielectric layer in a device selected from the group consisting of: a CMOS device, a high-voltage CMOS device, and an intelligent MEMS device.

18. In a method of making an integrated circuit device incorporating a film having a dielectric constant of between 10 and 50 at frequencies between 1 kHz and 1 MHz, comprising:

using a spin-on sol-gel process to deposit said film on a substrate forming part of said integrated device, said film having a composition (SiO 2 ) x (TiO 2 ) 1−x , where 0.50<x<0.75; and

annealing the resulting film in an oxygen-containing atmosphere at a temperature lying in the range of about 500° C. to 700° C.

19. A method as claimed in claim 18 , wherein said spin-on sol-gel process uses as precursors for said film tetrabutyloxytitanium (TBOT) and tetramethoxysilane (TEOS).

20. A method as claimed in claim 19 , wherein said precursors are diluted with C 2 H 5 OH.

21. In a method of making an integrated device incorporating a film with high dielectric constant, the improvement wherein said film is made by:

mixing tetrabutyloxytitanium (TBOT) and tetramethoxysilane (TEOS) precursors to form a sol;

transforming said sol into a gel;

spin coating said gel onto a substrate to form a titanium silicate film having a composition SiO 2 ) x (TiO 2 ) 1−x , where 0.50<x<0.75; and

annealing said titanium silicate film in an oxygen-containing atmosphere at a temperature lying in the range of about 500° C. to 700° C.

22. A method as claimed in claim 21 , wherein said gel is aged in the presence of an acid for about 70–100 hours.