Interlayer adhesion promoter for low k materials

• US 20050173803A1
• Filed: 09/20/2002
• Published: 08/11/2005
• Est. Priority Date: 09/20/2002
• Status: Abandoned Application

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Naman, Ananth, Fan, Wenya, Lu, Victor, Zhou, De-Ling, Leung, Roger Y.
• Application Number:
  US10/517,575
• Publication Number:
  US 20050173803A1
• Time in Patent Office: Days
• US Class Current: 257/759
• 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 21/02216 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 21/02282 liquid deposition, e.g. spin-coating, sol-gel techniques, spray coating
• CPC Class Codes: H01L 21/02304 formation of intermediate layers, e.g. buffer layers, layers to improve adhesion, lattice match or diffusion barriers
• CPC Class Codes: H01L 21/02362 formation of intermediate layers, e.g. capping layers or diffusion barriers
• CPC Class Codes: H01L 21/314 Inorganic layers H01L21/3105, H01L21/32 take precedence
• CPC Class Codes: H01L 21/31695 Deposition of porous oxides or porous glassy oxides or oxide based porous glass
• 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

The invention relates to the production of multilayered dielectric structures and to semiconductor devices and integrated circuits comprising these structures. The structures of the invention are prepared by adhering a porous dielectric layer to a substantially nonporous capping layer via an intermediate adhesion promoting dielectric layer. A multilayered dielectric structure is prepared which has a porous dielectric layer which has a porosity of about 10% or more; b) an adhesion promoting dielectric layer on the porous dielectric layer which has a porosity of about 10% or less; and a substantially nonporous capping layer on the adhesion promoting dielectric layer.

Claims

1. A multilayered dielectric structure which comprises:

a) a porous dielectric layer which has a porosity of about 10% or more;

b) an adhesion promoting dielectric layer on the porous dielectric layer which has a porosity of about 10% or less; and

c) a substantially nonporous capping layer on the adhesion promoting dielectric layer.

2. The structure of claim 1 wherein the porous dielectric layer is further disposed on a substrate.

3. The structure of claim 1 wherein the porous dielectric layer has a porosity of from about 10% to about 90%.

4. The structure of claim 1 wherein the porous dielectric layer has a dielectric constant of from about 1.3 to about 3.0.

5. The structure of claim 1 wherein the combination of the porous dielectric layer and the adhesion promoting dielectric layer has an effective dielectric constant of from about 1.4 to about 3.0.

6. The structure of claim 1 wherein the porous dielectric layer comprises a material selected from the group consisting of a nanoporous silica, silicon oxide, an organosilsesquioxane, a polysiloxane, a poly(arylene ether), a polyimide and combinations thereof.

7. The structure of claim 1 wherein the adhesion promoting dielectric layer has a porosity of from about 0.1% to about 13%.

8. The structure of claim 1 wherein the adhesion promoting dielectric layer has a dielectric constant of about 2.8 or more.

9. The structure of claim 1 wherein the adhesion promoting dielectric layer has a dielectric constant of from about 2.8 to about 4.0.

10. The structure of claim 1 wherein the adhesion promoting dielectric layer comprises a material selected from the group consisting of a nanoporous silica, silicon oxide, an organosilsesquioxane, a polysiloxane, a poly(arylene ether), a polyimide and combinations thereof.

11. The structure of claim 1 wherein the capping layer has a dielectric constant of from about 2.8 to about 7.0.

12. The structure of claim 1 wherein the capping layer comprises a material selected from the group consisting of silicon carbide, silicon oxide, silicon nitride, silicon oxynitride, tungsten, tungsten nitride, tantalum, tantalum nitride, titanium, titanium nitride, titanium zirconium nitride, and combinations thereof.

13. The structure of claim 1 wherein the ratio of the thickness of the adhesion promoting dielectric layer to the total thickness of the adhesion promoting dielectric layer and the porous dielectric layer ranges from about 0.02 to about 30.

14. The structure of claim 1 wherein the adhesion promoting dielectric layer, the porous dielectric layer, and the capping layer are adhered to one another to a degree sufficient to pass the ASTM D 3359-97 test.

15. A microelectronic device which comprises a substrate, a porous dielectric layer on the substrate, said porous dielectric layer having a porosity of about 10% or more;

an adhesion promoting dielectric layer on the porous dielectric layer which has a porosity of about 10% or less; and

a substantially nonporous capping layer on the adhesion promoting dielectric layer.

16. A method for forming a multilayered dielectric structure comprising:

a) coating a substrate with a first composition comprising a pre-polymer, solvent, optional catalyst, and a porogen to form a film, cross-linking the composition to produce a gelled film, and heating the gelled film at a temperature and for a duration effective to remove substantially all of said porogen to produce a porous dielectric layer which has a porosity of about 10% or more;

b) coating the porous dielectric layer with a second composition comprising a silicon containing pre-polymer, solvent, and optional catalyst;

followed by cross-linking and heating to produce an adhesion promoting dielectric layer on the porous dielectric layer which has a porosity of about 10% or less; and

c) forming a substantially nonporous capping layer on the adhesion promoting dielectric layer.

17. The method of claim 16 wherein the second composition is absent of a porogen.

18. The method of claim 16 wherein the first composition and the second composition comprises a metal-ion-free catalyst selected from the group consisting of onium compounds and nucleophiles.

19. The method of claim 16 wherein the first composition comprises a porogen which is selected from the group consisting of a polyalkylene oxide, a monoether of a polyalkylene oxide, fully end-capped polyalkylene oxides, Crown ethers, an aliphatic polyester, an acrylic polymer, an acetal polymer, a poly(caprolatactone), a poly(valeractone), a poly(methyl methacrylate), a poly (vinylbutyral) and combinations thereof.

20. The method of claim 16 wherein the first composition and the second composition comprises a silicon containing pre-polymer selected from the group consisting of an acetoxysilane, an ethoxysilane, a methoxysilane, and combinations thereof.

22. The method of claim 16 wherein the first composition and the second composition comprises a silicon containing pre-polymer selected from the group consisting of tetraacetoxysilane, a C₁ to about C₆ alkyl or aryl-triacetoxysilane, and combinations thereof.

23. The method of claim 22 wherein said triacetoxysilane is methyltriacetoxysilane.

21. The method of 16 wherein the coating of the second composition onto the porous dielectric layer results in an infiltration of the second composition into the porous dielectric layer of about 300 angstroms or less.