SiCOH dielectric

• US 20070173071A1
• Filed: 01/20/2006
• Published: 07/26/2007
• Est. Priority Date: 01/20/2006
• Status: Abandoned Application

• Current Assignee: Intel Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Nguyen, Son, Afzali-Ardakani, Ali, Grill, Alfred, Patel, Vishnubhai, Neumayer, Deborah, Gates, Stephen
• Application Number:
  US11/336,726
• Publication Number:
  US 20070173071A1
• Time in Patent Office: Days
• US Class Current: 438/781
• 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 21/02304 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 21/02362 formation of intermediate layers, e.g. capping layers or diffusion barriers
• CPC Class Codes: H01L 21/31695 Deposition of porous oxides or porous glassy oxides or oxide based porous glass
• CPC Class Codes: H01L 21/7682 the dielectric comprising air gaps
• CPC Class Codes: H01L 21/76829 characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers
• CPC Class Codes: H01L 21/76832 Multiple layers
• CPC Class Codes: H01L 21/76834 formation of thin insulating films on the sidewalls or on top of conductors H01L21/76831 takes precedence
• CPC Class Codes: H01L 2221/1047 the air gaps being formed by pores in the dielectric
• 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

A porous composite material useful in semiconductor device manufacturing, in which the diameter (or characteristic dimension) of the pores and the pore size distribution (PSD) is controlled in a nanoscale manner and which exhibits improved cohesive strength (or equivalently, improved fracture toughness or reduced brittleness), and increased resistance to water degradation of properties such as stress-corrosion cracking, Cu ingress, and other critical properties is provided. The porous composite material is fabricating utilizing at least one bifunctional organic porogen as a precursor compound

Claims

1. A dielectric material comprising atoms of Si, C, O, and H and having a covalently bonded tri-dimensional random network structure in which a fraction of the C atoms are bonded as Si—

CH₃ functional groups, and another fraction of the C atoms are bonded as Si—

R—

Si, wherein R is —

[CH₂]_n—

, —

[HC═

CH]_n—

, —

[C≡

C]_n—

, or —

[CH₂C═

CH]_n—

, where n is greater than or equal to and the fraction of the total carbon atoms in the material that is bonded as Si—

R—

Si is between 0.01 and 0.49, wherein said material is a porous composite material comprising a first solid phase having a first characteristic dimension and a second phase comprised of pores having a second characteristic dimension, wherein the characteristic dimensions of at least one of said phases is controlled to a value of about 5 nm or less.

2. A method of forming a dielectric material comprising atoms of Si, C, O, and H comprising:

depositing a dielectric film comprising a first phase and a second phase onto a substrate utilizing at least a first precursor and a second precursor, wherein at least one of said first or second precursors is a bifunctional organic molecule forming a porogen in the film; and

removing said porogen from said dielectric film to provide a porous dielectric material comprising a first solid phase having a first characteristic dimension and a second solid phase comprised of pores having at second characteristic dimension, wherein the characteristic dimensions of at least one of said phases is controlled to a value of about 5 nm or less.

3. The method of claim 2 wherein said bifunctional organic molecule is comprised of a linear, branched, cyclic or polycyclic hydrocarbon backbone of —

[CH₂]_n—

, where n is greater than or equal to 1, and is substituted at only two sites by a functional group selected from alkenes, alkynes, ethers, 3 member oxiranes, epoxides, aldehydes, ketones, amines, hydroxyls, alcohols, carboxylic acids, nitrites, esters, amino, azido and azo.

4. The method of claim 3 wherein the functional groups are alkenes and the bifunctional organic molecule has the general formula [CH₂═

CH]—

[CH₂]_n—

[CH═

CH₂], where n is 1-8.

5. The method of claim 2 wherein said bifunctional organic molecule is one of cyclopentene oxide, isobutylene oxide, 2,2,3-trimethyloxirane, butadienemonoxide, bicycloheptadiene, 1,2-epoxy-5-hexene and 2-methyl-2-vinyloxirane, propadiene, butadiene, pentadiene, hexadiene, heptadiene, octadiene, nonadiene, decadiene, cyclopentadiene, cyclohexadiene, dialkynes, butadiene, pentadiene, hexadiene, heptadiene, octadiene, nonadiene, decadiene, cyclopentadiene, cyclohexadiene, propdiyne, butadiyne, diethers, diepoxides, dialdehydes, diketones, diamines, dihydroxyls, dialcohols, dicarboxylic acids, dinitriles, diesters, diazido, or diazo.

6. The method of claim 2 wherein one of said first or second precursors is a silicon containing molecule selected from the group of silane (SiH₄) derivatives having the molecular formulas SiR₄, disiloxane derivatives having the formula R₃SiOSiR₃, trisiloxane derivatives having the formula R₃SiOSiR₂SiOSiR₃, cyclic siloxanes, and cyclic Si containing compounds wherein the R substitutents may or may not be identical and are selected from H, alkyl, alkoxy, epoxy, phenyl, vinyl, allyl, alkenyl or alkynyl groups that may be linear, branched, cyclic, polycyclic and may be functionalized with oxygen, nitrogen or fluorine containing substituents.

7. The method of claim 6 wherein said organosilicon precursor is one of silane, methylsilane, dimethylsilane, trimethylsilane, tetramethylsilane, ethylsilane, diethylsilane, triethylsilane, tetraethylsilane, ethylmethylsilane, triethylmethylsilane, ethyldimethylsilane, ethyltrimethylsilane, diethyldimethylsilane, diethoxymethylsilane (DEMS), dimethylethoxysilane, dimethyldimethoxysilane, tetramethylcyclotetrasiloxane (TMCTS), octamethylcyclotetrasiloxane (OMCTS), ethoxyltrimethylsilane, ethoxydimethylsilane, dimethoxydimethylsilane, dimethoxymethylsilane, trimethoxyrnethylsilane, methoxysilane, dimethoxysilane, trimethoxysilane, tetramethoxysilane, ethoxysilane, diethoxysilane, triethoxysilane, tetraethoxysilane, methoxymethylsilane, dimethoxymethylsilane, trimethoxymethylsilane, methoxydimethylsilane, methoxytrimethylsilane, dimethoxyldimethylsilane, ethoxymethylsilane, ethoxydimethylsilane, ethoxytrimethylsilane, triethoxymethylsilane, diethoxydimethylsilane, ethylmethoxysilane, diethylmethoxysilane, triethylmethoxysilane, ethyldimethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane, ethoxymethylsilane, diethoxymethylsilane, triethoxymethylsilane, ethoxydimethylsilane, ethoxytrimethylsilane, diethoxyldimethylsilane, ethyldimethoxylmethylsilane, diethoxyethylmethylsilane, 1,3-disilolane, 1,1,3,3-tetramethoxy(ethoxy)-1,3-disilolane 1,1,3,3-tetramethyl-1,3-disilolane, vinylmethyldiethoxysilane, vinyltriethoxysilane, vinyldimethylethoxysilane, cyclohexenylethyltriethoxysilane, 1,1-diethoxy-1-silacyclopent-3-ene, divinyltetramethyldisiloxane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, epoxyhexyltriethoxysilane, hexavinyldisiloxane, trivinylmethoxysilane, trivinylethoxysilane, vinylmethylethoxysilane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, vinylpentamethyldisiloxane, vinyltetramethyldisiloxane, vinyltriethoxysilane, vinyltrimethoxysilane, 1,1,3,3,-tetrahydrido-1,3-disilacyclobutane;

1,1,3,3-tetramethoxy(ethoxy)-1,3 disilacyclobutane;

1,3-dimethyl-1,3-dimethoxy-1,3 disilacyclobutane;

1,3-disilacyclobutane, 1,3-dimethyl-1,3-dihydrido-1,3-disilylcyclobutane, 1,1,3,3, tetramethyl-1,3-disilacyclobutane, 1,1,3,3,5,5-hexamethoxy-1,3,5- trisilane, 1,1,3,3,5,5-hexahydrido-1,3,5-trisilane, 1,1,3,3,5,5-hexamethyl-1,3,5-trisilane, 1,1,1,3,3,3-hexamethoxy(ethoxy)-1,3-disilapropane, 1,1,3,3-tetramethoxy-1-methyl-1,3-disilabutane, 1,1,3,3-tetramethoxy-1,3-disilapropane, 1,1,1,3,3,3-hexahydrido-1,3-disilapropane, 3-(1,1-dimethoxy-1-silaethyl)-1,4,4-trimethoxy-1-methyl-1,4-disilpentane, methoxymethane 2-(dimethoxysilamethyl)-1,1,4-trimethoxy-1,4-disilabutane, methoxymethane 1,1,4-trimethoxy-1,4-disila-2-(trimethoxysilylmethyl)butane, dimethoxymethane, methoxymethane, 1,1,1,5,5,5-hexamethoxy-1,5-disilapentane, 1,1,5,5-tetramethoxy-1,5-disilahexane, 1,1,5,5-tetramethoxy-1,5-disilapentane, 1,1,1,4,4,4-hexamethoxy(ethoxy)-1,4-disilylbutane, 1,1,1,4,4,4,-hexahydrido-1,4-disilabutane, 1,1,4,4-tetramethoxy(ethoxy)-1,4-dimethyl-1,4-disilabutane, 1,4-bis-trimethoxy (ethoxy)silyl benzene, 1,4-bis-dimethoxymethylsilyl benzene, 1,4-bis-trihydrosilyl benzene, 1,1,1,4,4,4-hexamethoxy(ethoxy)-1,4-disilabut-2-ene, 1,1,1,4,4,4-hexamethoxy(ethoxy)-1,4-disilabut-2-yne, 1,1,3,3-tetramethoxy(ethoxy)-1,3-disilolane 1,3-disilolane, 1,1,3,3-tetramethyl-1,3-disilolane, 1,1,3,3-tetramethoxy(ethoxy)-1,3-disilane, 1,3-dimethoxy(ethoxy)-1,3-dimethyl-1,3-disilane, 1,3-disilane;

1,3-dimethoxy-1,3-disilane, 1,1-dimethoxy(ethoxy)-3,3-dimethyl-1-propyl-3-silabutane, 2-silapropane, 1,3-disilacyclobutane, 1,3-disilapropane, 1,5-disilapentane, or 1,4-bis-trihydrosilyl benzene.

8. The method of claim 2 wherein said removing said porogen comprises treating said dielectric film with at least one energy source which comprises a thermal energy source, UV light, electron beam, chemical, microwave or plasma.

9. The method of claim 8 wherein the at least one energy source is a UV light, that may be pulsed or continuous, and said step is performed at a substrate temperature from 300°

-450°

C., and with light that includes at least a UV wavelength between 150-370 nm.

10. A method of forming a dielectric material including atoms of Si, C, O and H comprising:

depositing a dielectric film comprising a first phase and a second phase onto a substrate utilizing at least a first precursor and a second precursor, wherein at least one of said first or second precursors is a bifunctional organic molecule comprised of a linear, branched, cyclic or polycyclic hydrocarbon backbone of —

[CH₂]n—

, where n is greater than or equal to 1, and is substituted at only two sites by a functional group selected from alkenes, alkynes, ethers, 3 member oxiranes, epoxides, aldehydes, ketones, amines, hydroxyls, alcohols, carboxylic acids, nitriles, esters, amino, azido and azo forming a porogen in the film; and

removing said porogen from said dielectric film to provide a porous composite material comprising a first solid phase having a first characteristic dimension and a second solid phase comprised of pores having at second characteristic dimension, wherein the characteristic dimensions of at least one of said phases is controlled to a value of about 5 nm or less.

11. The method of claim 10 wherein the bifunctional organic molecule has the general formula [CH₂═

CH]—

[CH₂]_n—

[CH═

CH₂], wherein n is 1-8 and the functional groups are alkenes.

12. The method of claim 10 wherein said bifunctional organic molecule is one of cyclopentene oxide, isobutylene oxide, 2,2,3-trimethyloxirane, butadienemonoxide, bicycloheptadiene, 1,2-epoxy-5-hexene and 2-methyl-2-vinyloxirane, propadiene, butadiene, pentadiene, hexadiene, heptadiene, octadiene, nonadiene, decadiene, cyclopentadiene, cyclohexadiene, dialkynes, butadiene, pentadiene, hexadiene, heptadiene, octadiene, nonadiene, decadiene, cyclopentadiene, cyclohexadiene, propdiyne, butadiyne, diethers, diepoxides, dialdehydes, diketones, diamines, dihydroxyls, dialcohols, dicarboxylic acids, dinitriles, diesters, diazido, or diazo.

13. The method of claim 10 wherein one of said first or second precursors is a silicon containing molecule selected from silane (SiH₄) derivatives having the molecular formulas SiR₄, disiloxane derivatives having the formula R₃SiOSiR₃, trisiloxane derivatives having the formula R₃SiOSiR₂SiOSiR₃, cyclic siloxanes, and cyclic Si containing compounds including cyclosiloxanes, cyclocarbosiloxanes cyclocarbosilanes wherein the R substitutents may or may not be identical and are selected from H, alkyl, alkoxy, epoxy, phenyl, vinyl, allyl, alkenyl or alkynyl groups that may be linear, branched, cyclic, polycyclic and may be functionalized with oxygen, nitrogen or fluorine containing substituents.

14. The method of claim 10 wherein said removing said porogen comprises treating said dielectric film with at least one energy source which comprises a thermal energy source, UV light, electron beam, chemical, microwave or plasma.

15. A method of forming a dielectric material including atoms of Si, C, O and H comprising:

depositing a dielectric film comprising a first phase and a second phase onto a substrate utilizing at least a first precursor and a second precursor, wherein at least one of said first or second precursors is a bifunctional organic molecule has the general formula [CH₂═

CH]—

[CH₂]_n—

[CH═

CH₂], wherein n is 1-8 and the functional groups are alkenes to form a porogen in said film; and

removing said porogen from said dielectric film to provide a porous composite material comprising a first solid phase having a first characteristic dimension and a second solid phase comprised of pores having at second characteristic dimension, wherein the characteristic dimensions of at least one of said phases is controlled to a value of about 5 nm or less.

16. The method of claim 15 wherein said bifunctional organic molecule is one of cyclopentene oxide, isobutylene oxide, 2,2,3-trimethyloxirane, butadienemonoxide, bicycloheptadiene, 1,2-epoxy-5-hexene and 2-methyl-2-vinyloxirane, propadiene, butadiene, pentadiene, hexadiene, heptadiene, octadiene, nonadiene, decadiene, cyclopentadiene, cyclohexadiene, dialkynes, butadiene, pentadiene, hexadiene, heptadiene, octadiene, nonadiene, decadiene, cyclopentadiene, cyclohexadiene, propdiyne, butadiyne, diethers.

17. The method of claim 15 wherein one of said first or second precursors is any silicon containing molecule selected from the group any Si containing compound including molecules selected from silane (SiH₄) derivatives having the molecular formulas SiR4, disiloxane derivatives having the formula R₃SiOSiR₃, trisiloxane derivatives having the formula R₃SiOSiR₂SiOSi R₃, cyclic siloxanes, and cyclic Si containing compounds wherein the R substitutents may or may not be identical and are selected from H, alkyl, alkoxy, epoxy, phenyl, vinyl, allyl, alkenyl or alkynyl groups that may be linear, branched, cyclic, polycyclic and may be functionalized with oxygen, nitrogen or fluorine containing substituents.

18. The method of claim 15 wherein said removing said porogen comprises treating said dielectric film with at least one energy source which comprises a thermal energy source, UV light, electron beam, chemical, microwave or plasma.

19. The method of claim 18 wherein the at least one energy source is a UV light, that may be pulsed or continuous, and said step is performed at a substrate temperature from 300°

-450°

C., and with light that includes at least a UV wavelength between 150-370 nm.