Post-deposition treatment to enhance properties of SI-O-C low films

• US 20030077857A1
• Filed: 11/12/2002
• Published: 04/24/2003
• Est. Priority Date: 08/17/1999
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Xia, Li-Qun, Gaillard, Frederic, Yieh, Ellie, Lim, Tian H.
• Granted Patent: US 6,858,923 B2
• Time in Patent Office: Days
• US Class Current: 438/200
• CPC Class Codes: C23C 16/0218 in a reactive atmosphere C23C16/0227 takes precedence
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02071 the processing being a delineation, e.g. RIE, of conductive layers
• CPC Class Codes: H01L 21/02126 the material containing Si, O, and at least one of H, N, C, F, or other non-metal elements, e.g. SiOC, SiOC:H or SiONC
• CPC Class Codes: H01L 21/02203 the layer being porous
• CPC Class Codes: H01L 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• 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 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02312 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/02337 treatment by exposure to a gas or vapour
• CPC Class Codes: H01L 21/0234 treatment by exposure to a plasma
• CPC Class Codes: H01L 21/02362 formation of intermediate layers, e.g. capping layers or diffusion barriers
• CPC Class Codes: H01L 21/3105 After-treatment
• CPC Class Codes: H01L 21/3146 Carbon layers, e.g. diamond-like layers
• CPC Class Codes: H01L 21/31604 Deposition from a gas or vapour H01L21/31691, H01L21/31695 take precedence
• CPC Class Codes: H01L 21/31612 on a silicon body
• CPC Class Codes: H01L 21/31633 Deposition of carbon doped silicon oxide, e.g. SiOC
• CPC Class Codes: H01L 21/76807 for dual damascene structures
• CPC Class Codes: H01L 21/76826 by contacting the layer with gases, liquids or plasmas
• CPC Class Codes: H01L 21/76837 : Filling up the space between adjacent conductive structures; Gap-filling properties of dielectrics
• CPC Class Codes: Y10S 438/931 : Silicon carbide semiconductor

Abstract

A method for providing a dielectric film having enhanced adhesion and stability. The method includes a post deposition treatment that densifies the film in a reducing atmosphere to enhance stability if the film is to be cured ex-situ. The densification generally takes place in a reducing environment while heating the substrate. The densification treatment is particularly suitable for silicon-oxygen-carbon low dielectric constant films that have been deposited at low temperature.

Claims

1. A method for forming an insulation layer over a substrate disposed in a substrate processing chamber, the method comprising:

(a) flowing a process gas into the substrate processing chamber;

(b) heating the substrate to form layer over the substrate with said process gas;

(c) densifying said layer; and

(d) thereafter, curing the layer.

2. The method of claim 1 wherein said densfiying includes heating the substrate in a reducing atmosphere.

3. The method of claim 2 wherein said reducing atmosphere comprises ammonia (NH₃) or hydrogen (H₂).

4. The method of claim 2 wherein said reducing atmosphere comprises ammonia (NH₃) at a pressure of between 200 and 700 torr during said densification.

5. The method of claim 4 wherein the substrate is heated to a temperature of between 300 and 500°

C. during said densification.

6. The method of claim 5 wherein the substrate is heated for between 1 and 5 minutes during said densification.

7. The method of any of the above claims, wherein the curing is done in a furnace.

8. The method of claim 7 wherein said curing heats the substrate to a temperature between 300 and 500°

C. for at least 15 minutes.

9. The method of any of the above claims, wherein said process gas includes an organosilane having at least one silicon-carbon bond.

10. The method of claim 9 wherein the organosilane precursor is selected from the group consisting of methylsilane, dimethylsilane, trimethylsilane, tetramethylsilane and phenylmethylsilane.

11. The method of claim 1 wherein said process gas further comprises ozone.

12. The method of claim 1 wherein said substrate is heated to a temperature of less than about 250°

C.

13. A substrate processing system comprising:

a housing defining a process chamber;

a substrate holder, adapted to hold a substrate during substrate processing;

a heater, operatively coupled to heat said substrate holder;

a gas delivery system configured to introduce gases into said process chamber;

a controller for controlling said gas delivery system and said heater; and

a memory coupled to said controller comprising a computer-readable medium having a computer-readable program embodied therein for directing operation of said controller, said computer-readable program including

a first set of instructions to control said gas delivery system to flow a process gas into the substrate processing chamber;

a second set of instructions to control said heater to heat the substrate holder to form a carbon-doped silicon oxide layer over the substrate with said process gas; and

a third set of instructions to control said substrate processing system to densify said carbon-doped silicon oxide layer.

14. A computer readable storage medium having a computer-readable program embodied therein for directing operation of a substrate processing system including a process chamber;

a substrate holder;

a heater, operatively coupled to heat said substrate holder;

a gas delivery system configured to introduce gases into said process chamber, said computer-readable program including instructions for operating said substrate processing system to form an insulation layer over a substrate disposed in the processing chamber in accordance with the following;

flowing a process gas into the substrate processing chamber;

heating the substrate to form a carbon-doped silicon oxide layer over the substrate with said process gas; and

densifying said carbon-doped silicon oxide layer.