Porous, film, wiring structure, and method of forming the same

• US 20040000718A1
• Filed: 06/30/2003
• Published: 01/01/2004
• Est. Priority Date: 01/27/1999
• Status: Active Grant

• Current Assignee: Godo Kaisha IP Bridge 1 (IP Bridge, Inc.)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Aoi, Nobuo
• Granted Patent: US 6,873,052 B2
• Time in Patent Office: Days
• US Class Current: 257/758
• 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 21/02216 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 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02282 liquid deposition, e.g. spin-coating, sol-gel techniques, spray coating
• 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 21/3122 layers comprising polysiloxane compounds
• CPC Class Codes: H01L 21/31695 Deposition of porous oxides or porous glassy oxides or oxide based porous glass
• CPC Class Codes: H01L 21/76802 by forming openings in dielectrics
• CPC Class Codes: H01L 21/76807 for dual damascene structures
• CPC Class Codes: H01L 21/76814 post-treatment or after-treatment, e.g. cleaning or removal of oxides on underlying conductors
• CPC Class Codes: H01L 21/7682 the dielectric comprising air gaps
• CPC Class Codes: H01L 21/76826 by contacting the layer with gases, liquids or plasmas
• CPC Class Codes: H01L 21/76835 Combinations of two or more different dielectric layers having a low dielectric constant H01L21/76832 takes precedence
• CPC Class Codes: H01L 2221/1036 Dual damascene with different via-level and trench-level dielectrics
• CPC Class Codes: H01L 2221/1047 the air gaps being formed by pores in the dielectric
• CPC Class Codes: H01L 23/5222 Capacitive arrangements or effects of, or between wiring layers other capacitive arrangements H01L23/642
• CPC Class Codes: H01L 23/5329 Insulating materials
• 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
• CPC Class Codes: H01L 2924/12044 : OLED

Abstract

An organic-inorganic hybrid film is deposited on a substrate by introducing, into a vacuum chamber, a gas mixture of a silicon alkoxide and an organic compound and generating a plasma derived from the gas mixture. Then, a hydrogen plasma process is performed with respect to the organic-inorganic hybrid film by introducing, into the vacuum chamber, a gas containing a reducing gas and generating a plasma derived from the gas. As a result, an organic component in the organic-inorganic hybrid film eliminates therefrom and numerous fine holes are formed in hollow portions from which the organic component has eliminated, whereby a porous film composed of the organic-inorganic hybrid film is obtained.

Claims

1. A wiring structure comprising:

a first inter-layer dielectric formed on a substrate and having a contact hole, said first inter-layer dielectric being composed of a porous film having a relatively low porosity;

a second inter-layer dielectric formed on said first inter-layer dielectric and having a wire groove, said second inter-layer dielectric being composed of a porous film having a relatively high porosity;

a contact composed of a metal film filled in said contact hole; and

a metal wire composed of a metal film filled in said wire groove.

2. The structure of claim 1, wherein the porous film is formed by performing a plasma process using a plasma derived from a gas containing a reducing gas with respect to an organic-inorganic hybrid film,

3. The structure of claim 2, wherein the organic-inorganic hybrid film is deposited by plasma enhanced CVD using a gas mixture of a silicon alkoxide and an organic compound as a reactive gas.

4. The structure of claim 3, wherein the silicon alkoxide is an organic silicon alkoxide represented by the general formula:

R¹Si(OR²)₃ where R¹ and R² are the same or different, each representing an alkyl group or an aryl group.

5. The structure of claim 3, wherein the reducing gas contains a hydrogen gas or an ammonia gas.

6. The stricture of claim 2, wherein the organic-inorganic hybrid film has a siloxane skeleton.

7. The structure of claim 6, wherein the reducing gas contains a nitrogen atom.

8. The structure of claim 7, wherein the reducing gas contains an ammonia gas.

9. The structure of claim 6, wherein the reducing gas contains a hydrogen atom.

10. The structure of claim 9, wherein the reducing gas contains a hydrogen gas or an ammonia gas.

11. The structure of claim 1, wherein the porous film is formed by performing a thermal treatment in an atmosphere containing a reducing gas with respect to the organic-inorganic hybrid film.

12. The structure of claim 11, wherein the organic-inorganic hybrid film is deposited by plasma enhanced CVD using a gas mixture of a silicon alkoxide and an organic compound as a reactive gas.

13. The structure of claim 12, wherein the silicon alkoxide is an organic silicon alkoxide represented by the general formula:

R¹ Si(OR²)₃ where R¹ and R² are the same or different, each representing an alkyl group or an aryl group.

14. The structure of claim 12, wherein the reducing gas contains a hydrogen gas or an ammonia gas.