Low k and ultra low k SiCOH dielectric films and methods to form the same
View Patent ↗Dielectric materials including elements of Si, C, O and H having specific values of mechanical properties (tensile stress, elastic modulus, hardness cohesive strength, crack velocity in water) that result in a stable ultra low k film which is not degraded by water vapor or integration processing are provided. The dielectric materials have a dielectric constant of about 2.8 or less, a tensile stress of less than 45 MPa, an elastic modulus from about 2 to about 15 GPa, and a hardness from about 0.2 to about 2 GPa. Electronic structures including the dielectric materials of the present invention as well as various methods of fabricating the dielectric materials are also provided.
1. A dielectric material comprising elements of Si, C, O, H having a dielectric constant of about 2.8 or less, a tensile stress of less than 45 MPa, an elastic modulus from about 2 to about 15 GPa, and a hardness from about 0.2 to about 2 GPa, said dielectric material has a covalently bonded tri-dimensional network structure.
2. The dielectric material of claim 1 wherein said material has a cohesive strength from about 1.7 to about 4.5 J/m 2 .
3. The dielectric material of claim 1 wherein said material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness from about 1.1 to about 2.8 microns.
4. The dielectric material of claim 1 wherein the dielectric constant is 2.7, the tensile stress is less than 45 MPa, the elastic modulus is from about 9 to about 15 GPa, and the hardness is from about 0.5 to about 2 GPa.
5. The dielectric material of claim 4 wherein said material has a cohesive strength from about 4.0 to about 4.5 J/m 2 .
6. The dielectric material of claim 4 wherein said material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness of 2.8 microns.
7. The dielectric material of claim 1 wherein the dielectric constant is 2.6, the tensile stress is less than 45 MPa, the elastic modulus is from about 8 to about 13 GPa, and the hardness is from about 0.4 to about 1.9 GPa.
8. The dielectric material of claim 7 wherein the material has a cohesive strength from about 4.0 to about 4.5 J/m 2 .
9. The dielectric material of claim 7 wherein the material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness of 2.7 microns.
10. The dielectric material of claim 1 wherein the dielectric constant is 2.5, the tensile stress is less than 45 MPa, the elastic modulus is from about 7 to about 12 GPa, and the hardness is from about 0.35 to about 1.8 GPa.
11. The dielectric material of claim 10 wherein the material has a cohesive strength from about 2.5 to about 3.9 J/m 2 .
12. The dielectric material of claim 10 wherein the material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness of 2.5 microns.
13. The dielectric material of claim 1 wherein the dielectric constant is 2.4, the tensile stress is less than 40 MPa, the elastic modulus is from about 6 to about 11 GPa, and the hardness is from about 0.3 to about 1.7 GPa.
14. The dielectric material of claim 13 wherein the material has a cohesive strength from about 2.4 to about 3.8 J/m 2 .
15. The dielectric material of claim 13 wherein said material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness of 2.3 microns.
16. The dielectric material of claim 1 wherein the dielectric constant is 2.3, the tensile stress is less than 40 MPa, the elastic modulus is from about 5 to about 10 GPa, and the hardness is from about 0.25 to about 1.6 GPa.
17. The dielectric material of claim 16 wherein material has a cohesive strength from about 2.2 to about 3.7 J/m 2 .
18. The dielectric material of claim 16 wherein said material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness of 1.9 microns.
19. The dielectric material of claim 1 wherein the dielectric constant is 2.2, the tensile stress is less than 40 MPa, the elastic modulus is from about 4 to about 9 GPa, and the hardness is from about 0.2 to about 1.5 GPa.
20. The dielectric material of claim 19 wherein the material has a cohesive strength from about 2.0 to about 3.5 J/m 2 .
21. The dielectric material of claim 19 wherein the material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness of 1.5 microns.
22. The dielectric material of claim 1 wherein the dielectric constant is 2.1, the tensile stress is from about 20 to about 35 MPa, the elastic modulus is from about 3 to about 8 GPa, and the hardness is from about 0.2 to about 1.4 GPa.
23. The dielectric material of claim 22 wherein the material has a cohesive strength from about 1.8 to about 3.4 J/m 2 .
24. The dielectric material of claim 22 wherein the material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness of 1.3 microns.
25. The dielectric material of claim 1 wherein the dielectric constant is 2.0, the tensile stress is from about 20 to about 35 MPa, the elastic modulus is from about 2 to about 7 GPa, and the hardness is 0.2 GPa.
26. The dielectric material of claim 25 wherein the material has a cohesive strength is from about 1.7 to about 3.3 J/m 2 .
27. The dielectric material of claim 25 wherein the material has a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness of 1.1 microns.
28. The dielectric material of claim 1 wherein said covalently bonded tri-dimensional network structure further comprises Si—O bonds that produce an FTIR absorbance spectrum in which the ratio of the cage Si—O intensity to the network Si—O intensity is decreased using a treatment after deposition.
29. The dielectric material of claim 28 wherein said treatment uses at least an energy source selected from the group consisting of thermal, chemical, ultraviolet (UV) light, electron beam (e-beam), microwave and plasma.
30. The dielectric material of claim 1 wherein said material has a water contact angle that is greater than 70°.
31. The dielectric material of claim 1 wherein said dielectric material further comprises a multiplicity of nanometer-sized pores.
32. An interconnect structure comprising at least a dielectric material comprising elements of Si, C, O, H having a dielectric constant of about 2.8 or less, a tensile stress of less than 45 MPa, an elastic modulus from about 2 to about 15 GPa, and a hardness from about 0.2 to about 2 GPa and wiring regions, said dielectric material has a covalently bonded tri-dimensional network structure.
33. The electronic structure of claim 32 wherein the dielectric constant of the dielectric material is 2.7, the elastic modulus of the dielectric material is from about 9 to about 15 GPa, and the hardness of the dielectric material is from about 0.5 to about 2 GPa.
34. The electronic structure of claim 32 wherein the dielectric constant of the dielectric material is 2.6, the elastic modulus of the dielectric material is from about 8 to about 13 GPa, and the hardness of the dielectric material is from about 0.4 to about 1.9 GPa.
35. The electronic structure of claim 32 wherein the dielectric constant of the dielectric material is 2.5, the elastic modulus of the dielectric material is from about 7 to about 12 GPa, and the hardness of the dielectric material is from about 0.35 to about 1.8 GPa.
36. The electronic structure of claim 32 wherein the dielectric constant of the dielectric material is 2.4, the elastic modulus of the dielectric material is from about 6 to about 11 GPa, and the hardness of the dielectric material is from about 0.3 to about 1.7 GPa.
37. The electronic structure of claim 32 wherein the dielectric constant of the dielectric material is 2.3, the elastic modulus of the dielectric material is from about 5 to about 10 GPa, and the hardness of the dielectric material is from about 0.25 to about 1.6 GPa.
38. The electronic structure of claim 32 wherein the dielectric constant of the dielectric material is 2.2, the elastic modulus of the dielectric material is from about 4 to about 9 GPa, and the hardness of the dielectric material is from about 0.2 to about 1.5 GPa.
39. The electronic structure of claim 32 wherein the dielectric constant of the dielectric material is 2.1, the elastic modulus of the dielectric material is from about 3 to about 8 GPa, and the hardness of the dielectric material is from about 0.2 to about 1.4 GPa.
40. The electronic structure of claim 32 wherein the dielectric constant of the dielectric material is 2.0, the tensile stress of the dielectric material is from about 20 to about 35 MPa, the elastic modulus of the dielectric material is from about 2 to about 7 GPa, and the hardness of the dielectric material is 0.2 GPa.
41. The electronic structure of claim 32 wherein said dielectric material further comprises Si—O bonds that produce an FTIR absorbance spectrum in which the ratio of the cage Si—O intensity to the network Si—O intensity is decreased using a treatment after deposition.
42. The electronic structure of claim 41 wherein said treatment uses at least an energy source selected from the group consisting of thermal, chemical, ultraviolet (UV) light, electron beam (e-beam), microwave and plasma.
43. The electronic structure of claim 32 wherein the dielectric material has a water contact angle of greater than 70°.
44. The electronic structure of claim 32 wherein said dielectric material further comprises a multiplicity of nanometer-sized pores.
45. A dielectric material comprising elements of Si, C, O, H having a dielectric constant of about 2.8 or less, a tensile stress of less than 45 MPa, an elastic modulus from about 2 to about 15 GPa, a hardness from about 0.2 to about 2 GPa, a cohesive strength from about 1.7 to about 4.5 J/m 2 , and a crack development velocity in water of not more than 1×10 −10 m/sec for a film thickness from about 1.1 to about 2.8 microns.