Interconnect structures with patternable low-k dielectrics and method of fabricating same

• US 8,450,854 B2
• Filed: 07/22/2010
• Issued: 05/28/2013
• Est. Priority Date: 09/20/2007
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Lin, Qinghuang, Chen, Shyng-Tsong
• Primary Examiner(s): Such, Matthew W
• Assistant Examiner(s): HARRISTON, WILLIAM A
• Application Number:
  US12/841,359
• Publication Number:
  US 20100283157A1
• Time in Patent Office: 1,041 Days
• Field of Search: 257/488, 257/117, 257/E21.59, 257/E23.142, 438/618
• US Class Current: 257/773
• 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 21/02137 the material comprising alkyl silsesquioxane, e.g. MSQ
• 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 21/02348 treatment by exposure to UV light
• CPC Class Codes: H01L 21/31 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques encapsulating layers H01L21/56; After treatment of these layers; Selection of materials for these layers
• CPC Class Codes: H01L 21/3122 layers comprising polysiloxane compounds
• CPC Class Codes: H01L 21/76802 by forming openings in dielectrics
• CPC Class Codes: H01L 21/76808 involving intermediate temporary filling with material
• CPC Class Codes: H01L 21/76832 Multiple layers
• 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 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 23/5329 Insulating materials
• 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
• CPC Class Codes: H01L 2924/12044 OLED

Abstract

The present invention provides an interconnect structure in which a patternable low-k material is employed as an interconnect dielectric material. Specifically, this invention relates to single-damascene and dual-damascene low-k interconnect structures with at least one patternable low-k dielectric. In general terms, the interconnect structure includes at least one patterned and cured low-k dielectric material located on a surface of a substrate. The at least one cured and patterned low-k material has conductively filled regions embedded therein and typically, but not always, includes Si atoms bonded to cyclic rings via oxygen atoms. The present invention also provides a method of forming such interconnect structures in which no separate photoresist is employed in patterning the patterned low-k material.

Claims

1. An interconnect structure comprising:

a substrate;

a patterned and cured antireflective coating located on an upper surface of the substrate;

a lower patterned and cured low-k material layer located directly on a surface of the patterned and cured antireflective coating; and

an abutting upper patterned and cured low-k material layer located on said lower patterned and cured low-k material layer, said lower and upper patterned and cured low-k material layers and said patterned and cured antireflective coating having conductively filled regions located therein and each of said cured and patterned low-k material layers has Si atoms bonded to cyclic rings via oxygen atoms.

2. The interconnect structure of claim 1 further comprising a patterned dielectric cap located between said substrate and said patterned and cured antireflective coating.

3. The interconnect structure of claim 1 wherein said lower and upper patterned and cured low-k dielectric material layers each comprise a cured functionalized polymer.

4. The interconnect structure of claim 3 wherein said cured functionalized polymer comprises a polymer of a hydrocarbon, a fluorinated hydrocarbon, a siloxane, a silane, a carbosilane, an oxycarbosilane, an organosilicate or a silsesquioxane.

5. An interconnect structure comprising:

a substrate;

a patterned and cured antireflective coating located atop a surface of the substrate;

a lower patterned and cured low-k material layer located directly on a surface of the patterned and cured antireflective coating; and

an abutting upper patterned and cured low-k material layer located on said lower patterned and cured low-k material layer, said lower and upper patterned and cured low-k material layers and said patterned and cured antireflective coating having conductively filled regions located therein.

6. The interconnect structure of claim 5 further comprising a patterned dielectric cap located between said substrate and said patterned and cured antireflective coating.

7. A method of fabricating an interconnect structure comprising:

forming an antireflective coating atop a surface of a substrate;

providing at least one patternable low-k material directly on an upper surface of the antireflective coating;

forming at least one interconnect pattern within said at least one patternable low-k material, said at least one interconnect pattern is formed without utilizing a separate photoresist material;

curing said at least one patternable low-k material into a dielectric material having a dielectric constant of not more than 4.3;

forming an opening in said antireflective coating; and

filing said interconnect pattern within said at least one patternable low-k material and said opening in said antireflective coating with a conductive material.

8. The method of claim 7 wherein said at least one patternable low-k material is a functionalized polymer having one or more irradiation/acid-sensitive imageable groups.

9. The method of claim 8 wherein said functionalized polymer comprises a polymer of a hydrocarbon, a fluorinated hydrocarbon, a siloxane, a silane, a carbosilane, an oxycarbosilane, an organosilicate or a silsesquioxane.

10. The method of claim 7 wherein said curing comprises a thermal cure, an electron beam cure, an UV cure, an ion beam cure, a plasma cure, a microwave cure or any combination thereof.

11. A method of fabricating a dual-damascene interconnect structure comprising:

forming an antireflective coating atop a surface of a substrate;

providing a first patternable low-k material directly on an upper surface of said antireflective coating;

forming first interconnect patterns within the first patternable low-k material;

providing a second patternable low-k material on top of the first patternable low-k material including said first interconnect patterns;

forming second interconnect patterns within said second patternable low-k material;

curing at least said second patternable low-k material into a dielectric material having a dielectric constant of not more than 4.3;

forming an opening in said antireflective coating; and

filing said first and second interconnect patterns and said opening with a conductive material.

12. The method of claim 11 wherein the first interconnect patterns are vias, and said second interconnect patterns are lines, wherein each line is interconnect to a via.

13. The method of claim 11 wherein said first and second patternable low-k materials are the same or different and comprise functionalized polymers having one or more irradiation/acid-sensitive imageable groups.

14. The method of claim 13 wherein said functionalized polymers comprise polymers of hydrocarbons, fluorinated hydrocarbons, siloxanes, silanes, carbosilanes, oxycarbosilanes, organosilicates or silsesquioxanes.

15. The method of claim 11 wherein said curing at least said second patternable low-k material comprises a thermal cure, an electron beam cure, an UV cure, an ion beam cure, a plasma cure, a microwave cure or any combination thereof.

16. The method of claim 11 wherein said first patternable low-k material is a cured negative-tone material and said second patternable low-k material is a positive or negative-tone material.

17. The method of claim 11 wherein said first patternable low-k material is a cured positive-tone material and said second patternable low-k material is a positive or negative-tone material.