WO2006058009A2 - Using zeolites to improve the mechanical strenght of low-k interlayer dielectrics - Google Patents

Using zeolites to improve the mechanical strenght of low-k interlayer dielectrics Download PDF

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WO2006058009A2
WO2006058009A2 PCT/US2005/042333 US2005042333W WO2006058009A2 WO 2006058009 A2 WO2006058009 A2 WO 2006058009A2 US 2005042333 W US2005042333 W US 2005042333W WO 2006058009 A2 WO2006058009 A2 WO 2006058009A2
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layer
polymer
zeolite
metal
precursor
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WO2006058009A3 (en
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Boyan Boyanov
Grant Kloster
Michael Goodner
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Intel Corp
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Intel Corp
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    • H10P14/6928—Inorganic materials composed of oxides, glassy oxides or oxide-based glasses containing silicon the material containing silicon and at least one metal element, e.g. metal silicate based insulators or metal silicon oxynitrides
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Definitions

  • Silica films such as SiO2 are used in the microelectronics industry as dielectrics.
  • a dielectric is described by its dielectric constant, more commonly known as the k-value of the dielectric.
  • Dielectrics are used to isolate metal lines or layers from one another. Using a dielectric with a low dielectric constant helps to lessen crosstalk, the undesired capacitive or inductive interaction of one part of the circuit to another. As device density on integrated circuits increases, the metal lines become smaller, and the distance between metal layers decreases. As device geometries decrease, crosstalk effects become significant. Crosstalk effects can be reduced by lowering the k-value of the dielectric. Current technology uses dielectrics with a k-value between 2.5 and 4.0.
  • Silica has a dielectric constant of about 4.0, which is too high to be useful for next generation integrated circuits. Since air has a dielectric constant of 1.0, one way to lower the dielectric constant of silica is to incorporate voids or pores into the silica. There are several drawbacks to using this approach in an integrated circuit manufacturing process. First, porous dielectrics are generally not mechanically stable enough to support subsequent polishing operations. Additionally, the porous dielectric may allow transport of metal through the dielectric layer.
  • Figure 1 is an illustration of a graph showing the mechanical strength of low-k dielectric materials as a function of dielectric constant.
  • Figure 2 is an illustration of hexagonal, lamellar, and cubic mesoporous materials.
  • Figure 3 is an illustration of a cross section of a damascene opening in a porous zeolite.
  • Figures 4A - 4B are flow diagrams illustrating processes according to embodiments of the present invention.
  • Figures 5A - 5G are illustrations of cross sections of a zeolite dielectric layer according to embodiments of the present invention.
  • microelectronic device and microelectronic device, are often used interchangeably in this field.
  • the present invention is applicable to all of the above as they are generally
  • the expression low dielectric constant material refers to materials having a
  • organic polymers for example, organic polymers, amorphous fluorinated carbons, nanofoams, silicon based insulators containing organic polymers, carbon doped oxides of
  • silicon and fluorine doped oxides of silicon have lower dielectric constants than
  • porosity of a dielectric lowers the k-value of the film, it also lowers the mechanical
  • Figure 1 is a graph (100) which illustrates the modulus of a
  • SiO2 silicon dioxide
  • SiOF fluorinated silicon oxide
  • porous silicon oxide based materials such as porous SiO2, SiOF, and CDO.
  • zeolite is characterized by a high degree of ordered porosity, a high mechanical
  • Figure 2 illustrates images of porous zeolite
  • Hexagonal 210, 212 and lamellar 220, 222 structures are closed systems that do not
  • Cubic structures 230 allow transport of materials through the surface of the film.
  • Chemical uptake may occur during etch
  • Porosity may be
  • ALD layer deposition
  • Figure 3 illustrates a cross sectional view of a porous zeolite low-k
  • a porous zeolite layer in a semiconductor interconnect structure.
  • the substrate is typically a wafer upon which other semiconductor manufacturing operations have been performed to
  • transistors form various electrical components, including, but not limited to transistors and
  • the etch stop layer may comprise silicon nitride
  • silicon carbide or another material.
  • Damascene or dual damascene openings (308) which may include trench
  • Trenches (308A) are formed in the zeolite layer (302), while via openings (308B)
  • a metal is formed through both the zeolite layer (302) and etch stop layer (306).
  • barrier layer (310) is formed over the damascene openings.
  • the metal barrier layer (310) is formed over the damascene openings.
  • CVD chemical vapor deposition
  • atomic layer may be formed by atomic layer
  • ALD atomic deposition
  • metal deposits may be formed inside of the pores (312). This may lead to
  • the internal pores of the zeolite may be sealed, yet the zeolite layer will
  • Figure 4A is a flow diagram illustrating a process in accordance with one
  • zeolite low-k dielectric layer is formed on a substrate.
  • the zeolite may be
  • the low-k material may be a spin-on or plasma-deposited monomer or
  • polymer or may be another low-k material which is able to penetrate the pores of
  • the low-k material may be a polymer which is dissolved
  • Impregnation of the zeolite by the low-k material may be either
  • a damascene or dual damascene opening may be
  • a barrier layer metal may be formed over the
  • the barrier layer is
  • metal may be comprised of copper or an alloy of copper.
  • the damascene opening may
  • a metal such as, but not limited to copper or a copper alloy as
  • layer material may be removed, typically by a chemical mechanical polishing
  • damascene or other interconnect structures may be formed within
  • FIG. 4B is a flow diagram illustrating a process in accordance with
  • zeolite nanoparticle/low-k precursor suspension may be formed using a zeolite nanoparticle/low-k precursor suspension
  • calcination may be used to treat the suspension.
  • the zeolite nanoparticles can be
  • Figures 5A through 5G illustrate cross-sectional views of a zeolite dielectric
  • Figure 5A illustrates a porous zeolite layer (504) having pores (505) formed
  • porous zeolite layer (504) is exposed to a low-k
  • the zeolite layer (504) may be impregnated with the precursor (506) using vapor, liquid, or supercritical fluid exposure.
  • the polymer precursor may be dissolved in another material, or may
  • Polymerization of the precursor (506) may be initiated via thermal, plasma,
  • polymerization may be initiated by
  • polymerization may be initiated by exposing the zeolite layer and
  • zeolite (504) may be directly impregnated with a long-chain, non-crosslinked
  • polymer (507) such as paralyene, poly(arylene ether)s (such as FLARETM from
  • Impregnation may be performed in either liquid or supercritical
  • the polymer may be dissolved in another material, or may be part of
  • the zeolite may be impregnated by using a hybrid
  • Figure 5C illustrates the zeolite layer (508) on a substrate (502) after the
  • pores have been partially or fully impregnated with a polymer or other low-k
  • the zeolite is more mechanically robust.
  • the polymer-filled zeolite layer is more mechanically robust.
  • ILD interlayer dielectric
  • the k-value of the resulting stack will be low.
  • Figure 5D illustrates the polymer-filled zeolite layer (508) after a
  • damascene opening (512) has been formed.
  • the damascene opening (512) may
  • a metal barrier layer (514) is formed over the
  • the metal barrier layer may be formed by chemical vapor
  • CVD chemical vapor deposition
  • ALD atomic layer deposition
  • zeolite (508) are filled by a polymer (510), the barrier metal may not penetrate the zeolite layer. Thus, metal deposits may not form in the pores, and the resulting
  • zeolite ILD layer may be more electrically robust.
  • Figure 5F illustrates the structure of Figure 5E after the damascene opening
  • (512) is filled with a metal (516).
  • the metal is copper or a
  • the metal (516) forms copper interconnects, creating damascene or
  • copper and barrier layer material is removed, typically by a chemical mechanical
  • CMP polishing
  • Damascene or dual damascene structures are formed within a zeolite layer
  • the polymer-filled zeolite (508) may act as a
  • a porous zeolite ILD may be impregnated with a
  • second low-k dielectric such as a polymer
  • the resulting structure may have a greater mechanical strength than a
  • porous zeolite because the pores have been filled with a polymer.
  • the k-value of the resulting structure may remain low because both the zeolite and
  • polymer are low-k materials.

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  • Internal Circuitry In Semiconductor Integrated Circuit Devices (AREA)
  • Silicates, Zeolites, And Molecular Sieves (AREA)
  • Polymers With Sulfur, Phosphorus Or Metals In The Main Chain (AREA)

Abstract

A method for impregnating the pores of a zeolite low-k dielectric layer with a polymer, and forming an interconnect structure therein, thus mechanically strengthening the dielectric layer and preventing metal deposits within the pores.

Description

USING ZEOLITES TO IMPROVE THE MECHANICAL STRENGTH OF LOW-
K INTERLAYER DIELECTRICS
BACKGROUND
[001] Silica films, such as SiO2, are used in the microelectronics industry as dielectrics. A dielectric is described by its dielectric constant, more commonly known as the k-value of the dielectric. Dielectrics are used to isolate metal lines or layers from one another. Using a dielectric with a low dielectric constant helps to lessen crosstalk, the undesired capacitive or inductive interaction of one part of the circuit to another. As device density on integrated circuits increases, the metal lines become smaller, and the distance between metal layers decreases. As device geometries decrease, crosstalk effects become significant. Crosstalk effects can be reduced by lowering the k-value of the dielectric. Current technology uses dielectrics with a k-value between 2.5 and 4.0.
[002] Silica has a dielectric constant of about 4.0, which is too high to be useful for next generation integrated circuits. Since air has a dielectric constant of 1.0, one way to lower the dielectric constant of silica is to incorporate voids or pores into the silica. There are several drawbacks to using this approach in an integrated circuit manufacturing process. First, porous dielectrics are generally not mechanically stable enough to support subsequent polishing operations. Additionally, the porous dielectric may allow transport of metal through the dielectric layer.
[003] BRIEF DESCRIPTION OF THE DRAWINGS
[004] A better understanding of the present invention can be obtained from the following detailed description in conjunction with the following drawings, in which: [005] Figure 1 is an illustration of a graph showing the mechanical strength of low-k dielectric materials as a function of dielectric constant. [006] Figure 2 is an illustration of hexagonal, lamellar, and cubic mesoporous materials. [007] Figure 3 is an illustration of a cross section of a damascene opening in a porous zeolite.
[008] Figures 4A - 4B are flow diagrams illustrating processes according to embodiments of the present invention.
[009] Figures 5A - 5G are illustrations of cross sections of a zeolite dielectric layer according to embodiments of the present invention.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
[0010] The terms chip, integrated circuit, monolithic device, semiconductor
device, and microelectronic device, are often used interchangeably in this field.
The present invention is applicable to all of the above as they are generally
understood in the field.
[0011] The terms contact and via both refer to structures for electrical connection
of conductors from different interconnect levels. These terms are sometimes used
in the art to describe both an opening in an insulator in which the structure will be
completed, and the completed structure itself. For purposes of this disclosure,
contact and via refer to the completed structure.
[0012] The expression low dielectric constant material refers to materials having a
lower dielectric constant than silicon dioxide, which has a dielectric constant of 4.
For example, organic polymers, amorphous fluorinated carbons, nanofoams, silicon based insulators containing organic polymers, carbon doped oxides of
silicon and fluorine doped oxides of silicon have lower dielectric constants than
silicon dioxide.
[0013] The letter k is often used to refer to dielectric constant. Similarly, the terms
high-k and low-k are used in this field to refer to high dielectric constant and low
dielectric constant respectively, where high means greater than the dielectric
constant of silicon dioxide, and low means lower than the dielectric constant of
silicon dioxide.
[0014] The parasitic capacitance seen by an interconnect line is a function of the
distance to another conductor and the dielectric constant of the material between
the conductors. However, increasing the spacing between interconnect lines
increases the physical size, and thus the cost, of an integrated circuit. Therefore,
in order to manufacture integrated circuits with low parasitic capacitance between
interconnect lines, it is desirable to electrically isolate the conductors from each
other with an insulator having a low dielectric constant.
[0015] One way to reduce the adverse effects of parasitic capacitance is to use low-
k materials as insulators in advanced microelectronics. To achieve low dielectric
constants, one can introduce porosity into the dielectric film. While increasing the
porosity of a dielectric lowers the k-value of the film, it also lowers the mechanical
strength of the film. Figure 1 is a graph (100) which illustrates the modulus of a
film as a function of k-value for three low-k dielectric films: carbon-doped oxide
(CDO), silicon dioxide (SiO2), and fluorinated silicon oxide (SiOF). As the
porosity of the dielectric increases, the k-value decreases, and the modulus or mechanical strength of the film decreases as well, thus making it more difficult to
integrate these porous dielectrics into the semiconductor manufacturing process.
[0016] Because of their ordered nature, zeolites have significantly higher strengths
than porous silicon oxide based materials such as porous SiO2, SiOF, and CDO. A
zeolite is characterized by a high degree of ordered porosity, a high mechanical
strength, and a low k-value. Figure 2 illustrates images of porous zeolite
structures 200 and their corresponding transmission electron micrographs 202.
Hexagonal 210, 212 and lamellar 220, 222 structures are closed systems that do not
allow transport of materials through the surface of the film. Cubic structures 230,
232 have channels running through the entire film that allow transport to and
from the surface.
[0017] The inherent porosity and permeability of zeolite dielectric layers poses
significant integration challenges when using these porous dielectrics in the
semiconductor manufacturing process. Chemical uptake may occur during etch
or clean, significantly increasing the dielectric constant. Porosity may
compromise the integrity of the metal barrier layer, leading to poor gap fill and
interline leakage. Finally, permeability and ion-exchange properties can result in
trapping of mobile ions, catalysts of undesirable reactions during barrier atomic
layer deposition (ALD).
[0018] Figure 3 illustrates a cross sectional view of a porous zeolite low-k
dielectric layer in a semiconductor interconnect structure. A porous zeolite layer
(302) containing pores (304) is formed on an etch stop layer (306) and an
underlying semiconductor substrate (300). The substrate is typically a wafer upon which other semiconductor manufacturing operations have been performed to
form various electrical components, including, but not limited to transistors and
conductive interconnections. The etch stop layer may comprise silicon nitride,
silicon carbide, or another material.
[0019] Damascene or dual damascene openings (308), which may include trench
(308A) and/ or via (308B) openings are formed in the porous zeolite layer.
Trenches (308A) are formed in the zeolite layer (302), while via openings (308B)
are formed through both the zeolite layer (302) and etch stop layer (306). A metal
barrier layer (310) is formed over the damascene openings. The metal barrier
layer may be formed by chemical vapor deposition (CVD) or by atomic layer
deposition (ALD).
[0020] When the metal barrier layer is deposited over the porous zeolite layer,
metal deposits may be formed inside of the pores (312). This may lead to
electrical shorts and/ or a low breakdown voltage for the dielectric.
[0021] By impregnating the pores of the zeolite layer with a second low-k
dielectric, the internal pores of the zeolite may be sealed, yet the zeolite layer will
retain its desirable mechanical and low-k properties.
[0022] Figure 4A is a flow diagram illustrating a process in accordance with one
embodiment of the present invention. First, as illustrated in block 402, a porous
zeolite low-k dielectric layer is formed on a substrate. The zeolite may be
synthesized either in situ on the wafer via spin-coating and subsequent
calcination, or a priori as a nanoparticle suspension followed by calcination. [0023] Next, as shown in block 404, the zeolite is impregnated with another low-k
material. The low-k material may be a spin-on or plasma-deposited monomer or
polymer, or may be another low-k material which is able to penetrate the pores of
the zeolite. Alternately, the low-k material may be a polymer which is dissolved
in another material, or may be a polymer which is part of a mixture with another
material. Impregnation of the zeolite by the low-k material may be either
complete or partial.
[0024] Once the pores of the zeolite have been partially or completely filled with a
polymer or other low-k material, a damascene or dual damascene opening may be
formed in the zeolite layer, as shown by block 406.
[0025] Next, as shown in block 408, a barrier layer metal may be formed over the
damascene opening and the zeolite layer. In one embodiment, the barrier layer
metal may be comprised of copper or an alloy of copper.
[0026] After the barrier layer metal has been formed, the damascene opening may
be filled with a metal, such as, but not limited to copper or a copper alloy as
shown in block 410. Thus, a damascene or dual damascene interconnect structure
is formed.
[0027] After the dual damascene structures are formed, excess copper and barrier
layer material may be removed, typically by a chemical mechanical polishing
(CMP) process, as illustrated in block 412. Although dual damascene structures
are described, damascene or other interconnect structures may be formed within
the zeolite dielectric layer as well. [0028] Figure 4B is a flow diagram illustrating a process in accordance with
another embodiment of the present invention. In this embodiment, the zeolite
layer may be formed using a zeolite nanoparticle/low-k precursor suspension
applied directly to the wafer, as illustrated by block 452. Next, the suspension
may be treated to form a polymer impregnated zeolite layer, as shown in block
454. In one embodiment, calcination may be used to treat the suspension.
Calcination of the suspension will allow the low-k precursor to polymerize within
the pores of the zeolite. Using this method, the zeolite nanoparticles can be
prepared with a significantly lower k-value (k < 2.0) than fully dense silica (k =
3.9).
[Q029] After the suspension has been treated to form a zeolite layer having
polymer-impregnated pores, subsequent processing may occur, including
formation of a damascene or dual damascene opening in the zeolite layer (block
456), formation of a barrier metal layer over the damascene opening and the
zeolite layer (block 458), filling the damascene opening with a metal (block 460),
and polishing the top surface of the metal (block 462). Each of these processes is
described in greater detail above, in conjunction with Fig. 4A.
[0030] Figures 5A through 5G illustrate cross-sectional views of a zeolite dielectric
layer formed in accordance with embodiments of the process set forth in Figure 4
and described above.
[0031] Figure 5A illustrates a porous zeolite layer (504) having pores (505) formed
on a substrate (502). The porous zeolite layer (504) is exposed to a low-k
polymer precursor (506). The zeolite layer (504) may be impregnated with the precursor (506) using vapor, liquid, or supercritical fluid exposure. One
appropriate precursor which may be used is divinyl siloxane-benzocyclobutene
(DVS-BCB), which forms a low-k siloxane-organic hybrid polymer upon
polymerization. Another group of precursors which may be used are the CDO
related precursors, which form a low-k silicon dioxide-based dielectric. In one
embodiment, the polymer precursor may be dissolved in another material, or may
be part of a mixture with another material.
[0032] Polymerization of the precursor (506) may be initiated via thermal, plasma,
or other means to facilitate polymerization during or subsequent to the
impregnation process. In one embodiment, polymerization may be initiated by
applying heat to the zeolite layer and the polymer precursor. In another
embodiment, polymerization may be initiated by exposing the zeolite layer and
the polymer precursor to a plasma.
[0033] In another embodiment, illustrated in Figure 5B, the pores (505) of porous
zeolite (504) may be directly impregnated with a long-chain, non-crosslinked
polymer (507), such as paralyene, poly(arylene ether)s (such as FLARE™ from
Honeywell), polyphenylene derivatives (such as a non-crosslinked version of
SiLK™ from Dow Chemical), or another thermally robust, low-k dielectric
material. Impregnation may be performed in either liquid or supercritical
solution, to enhance diffusion of the polymer into the zeolite structure. In one
embodiment, the polymer may be dissolved in another material, or may be part of
a mixture with another material. [0034] In another embodiment, the zeolite may be impregnated by using a hybrid
method in which a macromonomer, such as oligomeric polyphenylene, is
introduced into the zeolite matrix and then subsequently reacted to form a
crosslinked network. The ability to modify the chemical properties of the zeolite
host over a wide range by using specific additives makes it possible to tailor the
zeolite to specific applications.
[0035] Figure 5C illustrates the zeolite layer (508) on a substrate (502) after the
pores have been partially or fully impregnated with a polymer or other low-k
material (510). Because the pores of the zeolite have been filled with a low-k
polymer, the zeolite is more mechanically robust. The polymer-filled zeolite layer
may act as mechanical reinforcement for the interlayer dielectric (ILD) stack
during subsequent process operations. Also, because the k-value of both the
zeolite and the polymer is low, the k-value of the resulting stack will be low.
[0036] Figure 5D illustrates the polymer-filled zeolite layer (508) after a
damascene opening (512) has been formed. The damascene opening (512) may
include a via region (512B) and a trench region (512A), and may be formed by
photolithography and etch operations. Because the pores of the zeolite are sealed
by the polymer (510), chemical uptake, ion exchange, and catalysis are prevented
during the photolithography, etch, and subsequent operations.
[0037] Next, as shown in Figure 5E, a metal barrier layer (514) is formed over the
damascene openings. The metal barrier layer may be formed by chemical vapor
deposition (CVD) or by atomic layer deposition (ALD). Because the pores of the
zeolite (508) are filled by a polymer (510), the barrier metal may not penetrate the zeolite layer. Thus, metal deposits may not form in the pores, and the resulting
zeolite ILD layer may be more electrically robust.
[0038] Figure 5F illustrates the structure of Figure 5E after the damascene opening
(512) is filled with a metal (516). In one embodiment, the metal is copper or a
copper alloy. The metal (516) forms copper interconnects, creating damascene or
dual damascene interconnect structures.
[0039] After the damascene or dual damascene structures are formed, excess
copper and barrier layer material is removed, typically by a chemical mechanical
polishing (CMP) process. The resulting structure is illustrated in Figure 5G.
Damascene or dual damascene structures (520) are formed within a zeolite layer
having polymer filled pores. The polymer-filled zeolite (508) may act as a
mechanical reinforcement for the inter-layer dielectric (ILD) stack during the CMP
process and subsequent manufacturing operations.
[0040] Thus, as described above, a porous zeolite ILD may be impregnated with a
second low-k dielectric, such as a polymer, so as to seal the internal pores of the
zeolite. The resulting structure may have a greater mechanical strength than a
porous zeolite, because the pores have been filled with a polymer. Additionally,
the k-value of the resulting structure may remain low because both the zeolite and
polymer are low-k materials.
[0041] In the foregoing specification, the invention has been described with
reference to specific exemplary embodiments thereof. It will, however, be evident
that various modifications and changes may be made thereto without departing
from the broader spirit and scope of the invention as set forth herein. The specification and drawings are, accordingly, to be regarded in an illustrative sense
rather than a restrictive sense.

Claims

IN THE CLAIMSWe claim:
1. A method comprising: forming a zeolite layer on a substrate, wherein the zeolite layer contains pores; impregnating the pores of the zeolite layer with a polymer to form a polymer impregnated zeolite layer; forming an opening in the polymer impregnated zeolite layer; and forming a barrier layer over the damascene opening and the polymer impregnated zeolite layer.
2. The method of claim 1, wherein impregnating the pores of the zeolite layer with a polymer comprises exposing the zeolite layer to a polymer precursor and subsequently initiating polymerization.
3. The method of claim 2, wherein the polymer precursor is selected from a group consisting of divinyl siloxane-benzocyclobutene (DVS-BCB), and carbon doped oxide (CDO).
4. The method of claim 2, wherein the polymer precursor is in vapor form.
5. The method of claim 2, wherein the polymer precursor is in liquid form.
6. The method of claim 2, wherein the polymer precursor is in supercritical fluid form.
7. The method of claim 2, wherein the polymer precursor is dissolved in another material.
8. The method of claim 2, wherein the polymer precursor is part of a mixture with another material.
9. The method of claim 2, wherein initiating polymerization comprises heating the zeolite layer and the polymer precursor.
10. The method of claim 2, wherein initiating polymerization comprises exposing the zeolite layer and the polymer precursor to a plasma.
11. The method of claim 1, wherein impregnating the pores of the zeolite layer with a polymer comprises exposing the zeolite layer to the polymer.
12. The method of claim 11, wherein the polymer is a liquid.
13. The method of claim 11, wherein the polymer is a supercritical solution.
14. The method of claim 11, wherein the polymer is dissolved in another material.
15. The method of claim 11, wherein the polymer is part of a mixture with another material.
16. The method of claim 11, wherein the polymer comprises a long-chain, non- crosslinked polymer.
17. The method of claim 16, wherein the polymer is selected from a group consisting of paralyene, poly(arylene ether)s, and polyphenylene derivatives.
18. The method of claim 1, wherein the barrier layer comprises a layer of metal.
19. The method of claim 1, further comprising filling the opening with a metal layer.
20. The method of claim 19, further comprising polishing the metal layer
21. The method of claim 19, wherein the metal layer comprises a copper alloy.
22. A method comprising: applying a zeolite-nano particle precursor suspension to a substrate; treating the suspension to form a polymer impregnated zeolite layer; forming an opening in the polymer impregnated zeolite layer; and forming a barrier layer over the opening and the polymer impregnated zeolite layer.
23. The method of claim 22, wherein treating the suspension to form a polymer impregnated zeolite layer comprises calcining the suspension.
24. The method of claim 22, wherein the barrier layer comprises a layer of metal.
25. The method of claim 22, further comprising filling the opening with a metal layer.
26. The method of claim 25, further comprising polishing the metal layer
27. The method of claim 25, wherein the metal layer comprises a copper alloy.
28. An interconnect structure comprising: a via and a trench defined by a polymer impregnated zeolite dielectric layer, which is disposed above an underlying layer; a barrier layer disposed on the surface of the polymer impregnated zeolite dielectric; and a conductive material disposed in the via opening and in the trench.
29. The interconnect structure of claim 28, wherein the barrier layer is a metal layer.
30. The interconnect structure of claim 28, wherein the conductive material comprises a copper alloy.
31. The interconnect structure of claim 28, wherein the underlying layer is a semiconductor substrate.
32. The interconnect structure of claim 31, further comprising an etch stop layer formed over the conductive material.
33. The interconnect structure of claim 32, wherein the etch stop layer comprises a silicon carbide layer.
PCT/US2005/042333 2004-11-22 2005-11-17 Using zeolites to improve the mechanical strenght of low-k interlayer dielectrics Ceased WO2006058009A2 (en)

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TWI282123B (en) 2007-06-01

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