Ultralow dielectric constant material as an intralevel or interlevel dielectric in a semiconductor device

• US 20030234450A1
• Filed: 06/19/2002
• Published: 12/25/2003
• Est. Priority Date: 10/25/2000
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Patel, Vishnubhai V., Grill, Alfred
• Granted Patent: US 6,768,200 B2
• Time in Patent Office: Days
• US Class Current: 257/759
• CPC Class Codes: C23C 16/401 containing silicon
• 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 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/3122 layers comprising polysiloxane compounds
• CPC Class Codes: H01L 21/31633 Deposition of carbon doped silicon oxide, e.g. SiOC
• 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

Abstract

There is provided a thermally stable ultralow dielectric constant film comprising Si, C, O and H atoms and having a covalently bonded tri-dimensional network structure and a dielectric constant of not more than 2.6. The dielectric constant film may additionally have a covalently bonded ring network. The covalently bonded tri-dimensional (i.e., three dimensional) network structure comprises Si—O, Si—C, Si—H, C—H and C—C covalent bonds and may optionally contain F and N. In the film, the Si atoms may optionally be partially substituted with Ge atoms. The dielectric constant film has a thickness of not more than 1.3 micrometers and a crack propagation velocity in water of less than 10⁻¹⁰ meters per second. There is further provided a back-end-of-the-line (BEOL) interconnect structure comprising the inventive dielectric film as a BEOL insulator, cap or hardmask layer.

Claims

1. A dielectric material comprising elements of Si, C, O and H, said dielectric material having a covalently bonded tri-dimensional network structure and a dielectric constant of not more than 2.6.

2. The dielectric material according to claim 1, wherein said dielectric constant is in a range from about 1.6 to about 2.6.

3. The dielectric material according to claim 1, wherein said dielectric constant is in a range from about 1.8 to about 2.2.

4. The dielectric material according to claim 1, wherein said dielectric constant is not more than 2.2.

5. The dielectric material according to claim 1, wherein said dielectric constant is not more than 2.1.

6. The dielectric material according to claim 1, wherein said covalently bonded tri-dimensional structure comprises Si—

O, Si—

C, Si—

H, C—

H and C—

C bonds.

7. The dielectric material according to claim 1, wherein said dielectric material comprises:

between about 5 and about 40 atomic percent of Si;

between about 5 and about 45 atomic percent of C;

between 0 and about 50 atomic percent of O; and

between about 10 and about 55 atomic percent of H.

8. The dielectric material according to claim 1, wherein said dielectric material further has a covalently bonded ring network.

9. The dielectric material according to claim 1, wherein said dielectric material is thermally stable to a temperature of at least 350°

C.

10. The dielectric material according to claim 1, wherein said Si is at least partially substituted by Ge.

11. The dielectric material according to claim 1, wherein said dielectric material further comprises at least one element selected from the group consisting of:

F, N and Ge.

12. The dielectric material according to claim 1, wherein said dielectric material further comprises a multiplicity of nanometer-sized pores.

13. The dielectric material according to claim 12, wherein diameters of said multiplicity of nanometer-sized pores are between about 0.3 and about 50 nanometers.

14. The dielectric material according to claim 12, wherein diameters of said multiplicity of nanometer-sized pores are between about 0.4 and about 10 nanometers.

15. The dielectric material according to claim 12, wherein said multiplicity of nanometer-sized pores occupies a volume between about 0.5% and about 50% of a volume of said dielectric material.

16. The dielectric material according to claim 1, wherein said dielectric material has a thickness of not more than 1.3 micrometers and a crack propagation velocity in water of less than 10⁻

9 meters per second.

17. The dielectric material according to claim 1, wherein said dielectric material has a thickness of not more than 1.3 micrometers and a crack propagation velocity in water of less than 10⁻

10 meters per second.

18. A back-end-of-the-line (BEOL) interconnect structure comprising a dielectric material as a BEOL insulator, cap or hardmask layer, said dielectric material comprising elements of Si, C, O and H, and having a covalently bonded tri-dimensional network structure and a dielectric constant of not more than 2.6.