NITROUS OXIDE ANNEAL OF TEOS/OZONE CVD FOR IMPROVED GAPFILL

• US 20070059896A1
• Filed: 10/16/2006
• Published: 03/15/2007
• Est. Priority Date: 09/19/2002
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Venkataraman, Shankar, Arghavani, Reza, Yuan, Zheng
• Granted Patent: US 7,674,727 B2
• Time in Patent Office: Days
• US Class Current: 438/407
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/402 Silicon dioxide
• CPC Class Codes: C23C 16/45512 Premixing before introduction in the reaction chamber
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02129 the material being boron or phosphorus doped silicon oxides, e.g. BPSG, BSG or PSG
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/02216 the compound being a molecule comprising at least one silicon-oxygen bond and the compound having hydrogen or an organic group attached to the silicon or oxygen, e.g. a siloxane
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/02312 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/31612 on a silicon body
• CPC Class Codes: H01L 21/76224 using trench refilling with dielectric materials trench filling with polycristalline silicon H01L21/763; together with vertical isolation, e.g. trench refilling in a SOI substrate H01L21/76264
• CPC Class Codes: H01L 21/76822 Modification of the material of dielectric layers, e.g. grading, after-treatment to improve the stability of the layers, to increase their density etc.
• CPC Class Codes: H01L 21/76828 thermal treatment
• CPC Class Codes: H01L 23/53295 Stacked insulating layers
• 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 of filling a gap defined by adjacent raised features on a substrate includes providing a flow of a silicon-containing processing gas to a chamber housing the substrate and providing a flow of an oxidizing gas to the chamber. The method also includes varying over time a ratio of the (silicon-containing processing gas):(oxidizing gas). The method also includes exposing the substrate to nitrous oxide at a temperature less than about 900° C. to anneal the deposited film.

Claims

1. A method of forming a silicon oxide layer on a substrate, comprising:

providing a flow of a silicon-containing processing gas to a chamber housing the substrate;

providing a flow of an oxidizing processing gas to the chamber;

causing a reaction between the silicon-containing processing gas and the oxidizing processing gas to form a silicon oxide layer by, at least in part, varying over time a ratio of the (silicon-containing processing gas);

(oxidizing gas); and

thereafter heating the substrate in the presence of nitrous oxide.

2. The method of claim 1, wherein:

providing a flow of a silicon-containing processing gas comprises providing a flow of tetraethylorthosilicate (TEOS); and

providing a flow of an oxidizing processing gas comprises providing a flow of ozone.

3. The method of claim 1, wherein causing a reaction between the silicon-containing processing gas and the oxidizing processing gas comprises regulating the pressure of the chamber to sub-atmospheric levels.

4. The method of claim 3, wherein the sub-atmospheric levels comprise pressures in a range from about 200 torr to less than about 760 torr.

5. The method of claim 1, wherein causing a reaction between the silicon-containing processing gas and the oxidizing processing gas comprises regulating the temperature of the chamber to a range from about 400°

C. to about 570°

C.

6. The method of claim 1, wherein heating the substrate in the presence of nitrous oxide comprises heating the substrate to a temperature in a range from about 750°

C. to about 1000°

C. in a furnace.

7. The method of claim 6, wherein heating the substrate in the presence of nitrous oxide further comprises introducing steam into the furnace.

8. The method of claim 1, wherein heating the substrate in the presence of nitrous oxide comprises heating the substrate to a temperature greater than or equal to 1000°

C. in a rapid thermal process for a duration greater than or equal to 1 minute.

9. A method of forming a silicon oxide layer on a substrate, comprising:

providing a flow of a silicon-containing processing gas to a chamber housing the substrate;

providing a flow of ozone to the chamber;

causing a reaction between the silicon-containing processing gas and the ozone to form a silicon oxide layer; and

heating the substrate in the presence of nitrous oxide in a furnace to a temperature in the range from about 750°

C. to about 1000°

C.

10. The method of claim 9, further comprising introducing steam into the furnace.

11. The method of claim 9, wherein the silicon-containing processing gas comprises tetraethylorthosilicate (TEOS).

12. A method of forming a silicon oxide layer on a substrate, comprising:

providing a flow of tetraethylorthosilicate (TEOS) processing gas to a chamber housing the substrate;

providing a flow of ozone to the chamber;

regulating the pressure of the chamber to a pressure in a range from about 200 torr to less than about 760 torr;

causing a reaction between the TEOS and the ozone to form a silicon oxide layer; and

heating the substrate in the presence of nitrous oxide.

13. The method of claim 12, wherein heating the substrate in the presence of nitrous oxide comprises heating the substrate in the presence of nitrous oxide in a furnace to a temperature in the range from about 750°

C. to about 1000°

C.

14. The method of claim 12, wherein heating the substrate in the presence of nitrous oxide comprises heating the substrate to a temperature greater than or equal to 1000°

C. in a rapid thermal process for a duration greater than or equal to 1 minute.

15. A method of forming a silicon oxide layer on a substrate, comprising:

providing a flow of tetraethylorthosilicate (TEOS) processing gas to a chamber housing the substrate;

providing a flow of ozone to the chamber;

regulating the pressure of the chamber to a pressure in the range from about 200 torr to less than about 760 torr;

varying over time a ratio of the (TEOS);

(ozone);

causing a reaction between the TEOS and the ozone to form a silicon oxide layer; and

heating the substrate in the presence of nitrous oxide in a furnace to a temperature in the range from about 750°

C. to about 1000°

C.

16. A method of filling a gap defined by adjacent raised features on a substrate, comprising:

providing a flow of a silicon-containing processing gas to a chamber housing the substrate;

providing a flow of an oxidizing gas to the chamber;

causing a reaction between the silicon-containing processing gas and the oxidizing gas to thereby deposit a film in the gap by, at least in part, varying over time a ratio of the (silicon-containing processing gas);

(oxidizing gas); and

thereafter, exposing the substrate to nitrous oxide at a temperature less than about 900°

C. to anneal the deposited film.

17. The method of claim 16, wherein exposing the substrate to nitrous oxide at a temperature less than about 900°

C. to anneal the deposited film comprises exposing the substrate to nitrous oxide at a temperature less than about 750°

C. to anneal the deposited film.

18. The method of claim 16, further comprising thereafter planarizing the film.

19. The method of claim 18, wherein planarizing the film comprises subjecting the film to chemical mechanical polishing.

20. A method of forming isolation structures in a silicon substrate, comprising:

etching trenches in the substrate;

providing a flow of a silicon-containing processing gas to a chamber housing the substrate;

providing a flow of an oxidizing gas to the chamber;

causing a reaction between the silicon-containing processing gas and the oxidizing processing gas to form a silicon oxide layer by, at least in part, varying over time a ratio of the (silicon-containing processing gas);

(oxidizing gas);

heating the substrate in the presence of nitrous oxide; and

thereafter, planarizing the layer.

21. The method of claim 20, wherein planarizing the layer comprises subjecting the layer to chemical mechanical polishing.

22. The method of claim 20, wherein causing a reaction between the silicon-containing processing gas and the oxidizing processing gas to form a silicon oxide layer comprises:

depositing a first portion of a film as a substantially conformal layer in the trenches by causing a reaction between the silicon-containing processing gas and the oxidizing gas, wherein depositing the conformal layer comprises varying over time a ratio of the (silicon-containing processing gas);

(oxidizing gas) and regulating the chamber to a pressure in a range from about 200 torr to about 760 torr throughout deposition of the conformal layer; and

thereafter, depositing a second portion of the film as a bulk layer, wherein depositing a second portion of the film comprises maintaining the ratio of the (silicon-containing processing gas);

(oxidizing gas) substantially constant throughout deposition of the bulk layer and regulating the chamber to a pressure in a range from about 200 torr to about 760 torr throughout deposition of the bulk layer.

23. The method of claim 22, wherein heating the substrate in the presence of nitrous oxide comprises exposing the substrate to nitrous oxide at a temperature less than about 900°

C. to anneal the deposited film.