Method and material for integration of fuorine-containing low-k dielectrics

• US 6,265,779 B1
• Filed: 08/11/1998
• Issued: 07/24/2001
• Est. Priority Date: 08/11/1998
• Status: Expired due to Term

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: International Business Machines Corporation
• Inventors: Grill, Alfred, Jahnes, Christopher Vincent, Saenger, Katherine Lynn, Patel, Vishnubhai Vitthalbhai
• Primary Examiner(s): Chaudhuri, Olik
• Assistant Examiner(s): DOAN, THERESA T
• Application Number:
  US09/132,608
• Time in Patent Office: 1,078 Days
• Field of Search: 438/618, 438/622, 438/623, 438/625, 438/627, 438/642, 438/643, 438/648, 438/650, 438/651, 438/652, 438/653, 438/655, 438/656, 257/635, 257/641, 257/642, 257/644, 257/650, 257/701, 257/702, 257/748, 257/750, 257/751, 257/754, 257/757, 257/759, 257/761-766, 257/770
• US Class Current: 257/759
• CPC Class Codes: H01L 21/02115 the material being carbon, e.g. alpha-C, diamond or hydrogen doped carbon
• CPC Class Codes: H01L 21/0212 the material being fluoro carbon compounds, e.g.(CFx) n, (CHxFy) n or polytetrafluoroethylene
• CPC Class Codes: H01L 21/02131 the material being halogen doped silicon oxides, e.g. FSG
• CPC Class Codes: H01L 21/3127 Layers comprising fluoro (hydro)carbon compounds, e.g. polytetrafluoroethylene
• 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 21/76831 in via holes or trenches, e.g. non-conductive sidewall liners
• 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 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76844 Bottomless liners
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 23/5222 Capacitive arrangements or effects of, or between wiring layers other capacitive arrangements H01L23/642
• CPC Class Codes: H01L 23/53223 Additional layers associated with aluminium layers, e.g. adhesion, barrier, cladding layers
• 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 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

Metal and insulator interconnect structures are described incorporating one or more layers of fluorinated dielectric insulation, one or more conductive wiring levels interconnected by vias and capping and/or liner materials to physically isolate the wiring levels and vias from the fluorinated dielectric such as fluorinated diamond like carbon which has a low dielectric constant. The invention overcomes the problem that can arise when fluorine in the fluorinated dielectric insulation reacts with other materials in the interconnect structure to produce unwanted fluorine-containing compounds that can interfere with the structure'"'"'s mechanical integrity or interconnect function.

Claims

1. An interconnect structure comprising one or more layers of fluorinated dielectric insulation and one or more layers of conductive wiring patterns electrically connected by conductive vias, said conductive wiring patterns and vias completely isolated from said fluorinated dielectric insulation by at least one fluorine-resistant capping material selected from the group consisting of Ag, Co, Cr, In, Ir, Mn, Pd, Pt, Sn, their oxides, fluorides, nitrides, and silicides, mixtures thereof, Si-containing DLC and Si-O-containing DLC.

2. The interconnect structure of claim 1 wherein said one or more layers of fluorinated dielectric insulation is selected from the group consisting of fluorinated diamond like carbon (FDLC), fluorinated amorphous carbon (FLAC), FDLC or FLAC with additives selected from the group containing H, Si, Ge, O, and N, fluorinated silicon glass (FSG), inorganic halogen-containing dielectrics, and organic halogen-containing dielectrics.

3. An interconnect structure comprising one or more layers of fluorinated dielectric insulation and one or more layers of conductive wiring patterns electrically connected by conductive vias, said conductive wiring pattern levels and vias isolated from the fluorinated dielectric on a first set of selected surfaces by at least one electrically insulating fluorine-resistant capping material, and isolated from the fluorinated dielectric on a second set of selected surfaces by at least one electrically conductive fluorine-resistant capping and/or liner material, at least one of said electrically conductive fluorine-resistant capping and/or liner material and said electrically insulating fluorine-resistant capping material selected from the group consisting of Ag, Co, Cr, In, Ir, Mn, Pd, Pt, Sn, their oxides, fluorides, nitrides and silicides, mixtures thereof, Si-containing diamond like carbon (DLC) and Si—

O-containing DLC.

4. The interconnect structure of claim 3 wherein said one or more layers of fluorinated dielectric insulation is selected from the group consisting of fluorinated diamond like carbon (FDLC), fluorinated amorphous carbon, FDLC or FLAC with additives selected from the group containing H, Si, Ge, O, and N, fluorinated silicon glass (FSG), inorganic halogen-containing dielectrics, and organic halogen-containing dielectrics.

5. The interconnect structure of claim 3 wherein said electrically insulating fluorine-resistant capping material is selected from the group consisting of magnesium oxide (MgO), Si-containing DLC and Si—

O-containing DLC.

6. The interconnect structure of claim 3 wherein said electrically conductive fluorine-resistant capping and/or liner material is selected from the group consisting of Cr, Co, and cobalt silicide (CoSi₂).

7. An interconnect structure comprising one or more layers of fluorinated dielectric insulation and one or more layers of conductive wiring patterns electrically connected by conductive vias, said conductive wiring pattern and vias isolated from said fluorinated dielectric insulation on a first set of selected surfaces by at least one electrically insulating fluorine-resistant capping material, and isolated from said fluorinated dielectric on a second set of selected surfaces by at least one fluorine-resistant sidewall capping material in combination with a conductive liner material, said electrically insulating fluorine-resistant capping material is selected from the group consisting of insulating oxides, nitrides, or fluorides of the elements Ag, Co, Cr, In, Ir, Mn, Sn, mixtures and multilayers thereof, Si-containing diamond like carbon (DLC), and Si—

O-containing DLC.

8. The interconnect structure of claim 7 wherein said fluorine-resistant sidewall capping material is selected from the group consisting of, magnesium oxide (MgO), Cr, Co, Si-containing DLC and Si—

O-containing DLC.

9. The interconnect structure of claim 8 wherein said one or more layers of fluorinated dielectric insulation is selected from the group consisting of fluorinated diamond like carbon (FDLC), fluorinated amorphous carbon (FLAC), FDLC or FLAC with additives selected from the group containing H, Si, O, and N, fluorinated silicon glass (FSG), inorganic halogen-containing dielectrics, and organic halogen-containing dielectrics.

10. The interconnect structure of claim 7 wherein said conductive liner material is selected from the group consisting of TaSiN, ZrN, ZrSiN, HfN, HfSiN, TiSiN, WN, WSiN and combinations thereof.

11. The interconnect structure of claim 8 wherein said electrically insulating fluorine-resistant capping material is selected from the group consisting of magnesium oxide (MgO), Si-containing DLC and Si—

O-containing DLC.

12. The interconnect structure of claim 8 wherein said fluorine-resistant sidewall capping material is selected from the group consisting of Ag, Co, Cr, In, Ir, Mn, Pd, Pt, Sn, their oxides, fluorides, nitrides and silicides, mixtures thereof, Si-containing DLC and Si—

O-containing DLC.

13. An interconnect structure comprising one or more layers of fluorinated dielectric insulation and one or more layers of conductive wiring patterns electrically connected by conductive vias, said conductive wiring pattern and vias isolated from said fluorinated dielectric insulation on a first set of selected surfaces by at least one electrically insulating fluorine-resistant capping material, and isolated from said fluorinated dielectric on a second set of selected surfaces by at least one conductive fluorine-resistant liner material in combination with a conductive liner material to provide a diffusion barrier to metal atoms in said conductive wiring patterns and vias, said electrically insulating fluorine-resistant capping material is selected from the group consisting of insulating oxides, nitrides, or fluorides of the elements Ag, Al—

Cu, Co, Cr, In, Ir, Mn, Sn, mixtures and multilayers thereof, Si-containing diamond like carbon DLC and Si—

O-containing DLC.

14. The interconnect structure of claim 13 wherein said one or more layers of fluorinated dielectric insulation is selected from the group consisting of fluorinated diamond like carbon (FDLC), fluorinated amorphous carbon (FLAC), FDLC or FLAC with additives selected from the group containing H, Si, Ge, O, and N, fluorinated silicon glass (FSG), inorganic halogen-containing dielectrics and inorganic halogen-containing dielectrics.

15. The interconnect structure of claim 13 wherein said electrically insulating fluorine-resistant capping material is selected from the group consisting of magnesium oxide (MgO), Si-containing DLC and Si—

O-containing DLC.

16. The interconnect structure of claim 13 wherein said conductive fluorine-resistant liner material is selected from the group consisting of Ag, Co, Cr, In, Ir, Mn, Pd, Pt, Sn, their conductive oxides, fluorides, nitrides and silicides and mixtures thereof.

17. The interconnect structure of claim 13 wherein said conductive fluorine-resistant liner material is selected from the group consisting of Cr, Co, and cobalt silicide (CoSi₂).

18. The interconnect structure of claim 13 wherein said conductive liner material is selected from the group consisting of refractory metals W and Ta, and refractory metal nitrides and metal silicon nitrides including TaSiN, ZrN, ZrSiN, HfN, HfSiN, TiSiN, WN, and WSiN and layered combinations thereof.