Sputtering method for forming dielectric films

• US 6,290,822 B1
• Filed: 12/23/1999
• Issued: 09/18/2001
• Est. Priority Date: 01/26/1999
• Status: Expired due to Term

• Current Assignee: Bell Semiconductor, LLC (Hilco Inc. (d/b/a Hilco Global))
• Original Assignee: Agere Systems Guardian Corp. (Broadcom, Inc.)
• Inventors: Zahurak, Susan M., Fleming, Robert McIenore, Wong, Yiu-Huen, Steigerwald, Michael Louis
• Primary Examiner(s): Nguyen, Nam
• Assistant Examiner(s): Cantelmo, Gregg
• Application Number:
  US09/472,332
• Time in Patent Office: 635 Days
• Field of Search: 204/192.22, 204/192.13, 204/192.15
• US Class Current: 204/192.22
• CPC Class Codes: C23C 14/083 of refractory metals or yttrium
• CPC Class Codes: C23C 14/5806 Thermal treatment
• CPC Class Codes: C23C 14/5873 Removal of material
• CPC Class Codes: H01L 21/02197 the material having a perovskite structure, e.g. BaTiO3
• CPC Class Codes: H01L 21/02266 deposition by physical ablation of a target, e.g. sputtering, reactive sputtering, physical vapour deposition or pulsed laser deposition
• CPC Class Codes: H01L 21/28185 with a treatment, e.g. annealing, after the formation of the gate insulator and before the formation of the definitive gate conductor
• CPC Class Codes: H01L 21/28194 by deposition, e.g. evaporation, ALD, CVD, sputtering, laser deposition H01L21/28202 takes precedence
• CPC Class Codes: H01L 21/31691 with perovskite structure
• CPC Class Codes: H01L 21/7682 the dielectric comprising air gaps
• CPC Class Codes: H01L 21/76828 thermal treatment
• CPC Class Codes: H01L 21/76888 By rendering at least a portion of the conductor non conductive, e.g. oxidation
• CPC Class Codes: H01L 23/5222 Capacitive arrangements or effects of, or between wiring layers other capacitive arrangements H01L23/642
• CPC Class Codes: H01L 23/5223 Capacitor integral with wiring layers
• CPC Class Codes: H01L 23/53233 Copper alloys
• CPC Class Codes: H01L 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 23/5329 Insulating materials
• CPC Class Codes: H01L 29/517 the insulating material comprising a metallic compound, e.g. metal oxide, metal silicate H01L29/518 takes precedence
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A method for forming a dielectric film having a desired composition comprising sputtering a dielectric material onto a substrate to produce an intermediary film, the intermediary film incorporating one or more elements in addition to those elements included in the desired composition of the dielectric film; and removing the one or more additional elements from the intermediary film to produce the dielectric film having the desired composition.

Claims

1. A method of forming a dielectric film having a desired composition comprising:

sputtering a high dielectric constant film onto a substrate to incorporate at least carbon into the high dielectric constant film in addition to those elements included in the desired composition of the high dielectric constant film wherein an ambient gas comprises Ar and CO₂ and the ratio of Ar to CO₂ is 1;

1; and

removing at least the carbon from the film.

2. The method of claim 1, wherein the dielectric film is a high dielectric constant film.

3. The method of claim 1, wherein the additional one or more elements are introduced with an ambient gas during the sputtering of the dielectric material.

4. The method of claim 1, wherein the sputtering of the dielectric material includes at least one of reactive sputtering, chemical sputtering, and RF sputtering.

5. The method of claim 1, wherein the removing of the one or more additional elements from the intermediary film includes annealing the intermediary film.

6. The method of claim 5, wherein the annealing of the intermediary film is performed in an oxidizing ambient.

7. The method of claim 6, wherein the oxidizing ambient comprises O₂ or NO₂.

8. The method of claim 1, wherein the removing of the one or more additional elements from the intermediary film includes performing a plasma treatment on the intermediary film.

9. The method of claim 8, wherein the removing of the one or more additional elements from the intermediary film further includes annealing the intermediary film.

10. The method of claim 1, wherein the dielectric material comprises Ta₂O₅, TiO₂, or ZrO₂.

11. The method of claim 10, wherein the additional one or more elements are introduced with said ambient gas during the sputtering of the dielectric material.

12. The method of claim 1, wherein the sputtering of the dielectric material occurs under the following conditions:

substrate temperature of approximately 23-350°

C.;

pressure of approximately 5-20 mtorr;

plasma power of approximately 200 watts; and

ambient gas flow rate of approximately 50 sccm per minute.

13. The method of claim 13, wherein the growth rate of the intermediary film is approximately 20 Å

/min.

14. The method of claim 13, wherein the removing of the one or more additional elements from the intermediary film includes microwave annealing the intermediary film in an oxidizing ambient.

15. The method of claim 14, wherein the oxidizing ambient comprises O₂ or NO₂.

16. A method of forming a dielectric film having a desired composition comprising:

sputtering a high dielectric constant film onto a substrate to incorporate at least carbon into the high dielectric constant film in addition to those elements included in the desired composition of the high dielectric constant film wherein an ambient gas comprises Ar and CO₂ and the ratio of Ar to CO₂ is 1;

1; and

annealing the film in an oxygen atmosphere.

17. The method of claim 16, wherein annealing includes removing at least the carbon from the film.