Methods and apparatus to enhance properties of Si-O-C low K films

• US 6,635,575 B1
• Filed: 08/07/2000
• Issued: 10/21/2003
• Est. Priority Date: 08/17/1999
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Xia, Li-Qun, Gaillard, Frederic, Yieh, Ellie, Lim, Tian H.
• Primary Examiner(s): GOUDREAU, GEORGE A
• Application Number:
  US09/633,196
• Time in Patent Office: 1,170 Days
• Field of Search: 438/697, 438/723, 438/720, 427/569, 134/1.2
• US Class Current: 438/697
• CPC Class Codes: C23C 16/0245 by etching with a plasma
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/56 After-treatment
• 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 21/022 the layer being a laminate, i.e. composed of sublayers, e.g. stacks of alternating high-k metal oxides adhesion layers or buffer layers H01L21/02304, H01L21/02362
• 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 21/3146 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

Abstract

A method for providing a dielectric film having enhanced adhesion and stability. Pre-deposition, post deposition and post cure treatments enhance adhesion of the dielectric film to an underlying substrate and overlying cap layer. The enhanced film is particularly useful as an intermetal or premetal dielectric layer in an integrated circuit. A pre-deposition treatment process with atomic hydrogen enhances film adhesion by reducing weakly bound oxides on the surface of the substrate. A post-deposition densification process in a reducing atmosphere enhances stability if the film is to be cured ex-situ. In a preferred embodiment, the layer a low dielectric constant film deposited from a process gas of ozone and an organosilane precursor having at least one silicon-carbon (Si—C) bond.

Claims

1. A process for depositing an intermetal dielectric film over a plurality of conductive lines, the process comprising:

treating the plurality of conductive lines with atomic hydrogen produced by dissociation of a hydrogen-containing gas in a remote source fluidly coupled to the processing chamber;

flowing a process gas comprising ozone and an organosilane precursor having at least one silicon-carbon bond into the substrate processing chamber;

heating the substrate to a temperature of between about 100-250°

C. to form a carbon-doped silicon oxide layer over the plurality of conductive lines; and

thereafter, curing the carbon-doped silicon oxide layer.

2. The method of claim 1 wherein the treatment with atomic hydrogen enhances adhesion of the insulation layer to the substrate.

3. The method of claim 1 wherein the atomic hydrogen reduces an oxide on a surface of said substrate.

4. The method of claim 1 wherein said remote source energizes the hydrogen containing gas with electromagnetic radiation.

5. The method of claim 4 wherein said electromagnetic radiation has a frequency of between 100 kilohertz (Hz) and 100 gigahertz (GHz).

6. The method of claim 5 wherein said electromagnetic radiation is in the form of microwaves having a frequency of about 2.2 GHz.

7. The method of claim 1 wherein the substrate is heated by a pedestal heater to between 100 and 150°

C. during said treating with atomic hydrogen.

8. The method of claim 1, wherein said curing is done in a conventional furnace at atmospheric pressure.

9. The method of claim 1, wherein said curing heats the substrate in a vacuum environment.

10. The method of claim 1, wherein said organosilane precursor is chosen from the group of methylsilane, dimethylsilane, trimethylsilane, tetramethylsilane, and phenylmethylsilane.