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Showing 1 to 8 of 8 (0.048 seconds)Spelling suggestions: "subject:"verkupferung"" "subject:"kupferung""
| 1 |
New Precursors for CVD Copper MetallizationNorman, John A. T., Perez, Melanie, Schulz, Stefan E., Waechtler, Thomas 02 October 2008 (has links) (PDF)
A novel CVD copper process is described using
two new copper CVD precursors, KI3 and KI5, for
the fabrication of IC or TSV (Through Silicon Via)
copper interconnects. The highly conformal CVD
copper can provide seed layers for subsequent
copper electroplating or can be used to directly
fabricate the interconnect in one step. These
new precursors are thermally stable yet chemically
reactive under CVD conditions, growing copper
films of exceptionally high purity at high growth
rates. Their thermal stability can allow for
elevated evaporation temperatures to generate
the high precursor vapor pressures needed for
deep penetration into high aspect ratio TSV vias.
Using formic acid vapor as a reducing gas with
KI5, copper films of > 99.99 atomic % purity
were grown at 250°C on titanium nitride at a
growth rate of > 1500 Å/min. Using
tantalum
nitride coated TSV type wafers, ~ 1700 Å of
highly conformal copper was grown at 225°C into
32 μm × 5 μm trenches with good adhesion. With
ruthenium barriers we were able to grow copper
at 125°C at a rate of 20 Å/min to give a
continuous ~ 300 Å copper film. In this respect,
rapid low temperature CVD copper growth offers
an alternative to the long cycle times associated
with copper ALD which can contribute to copper
agglomeration occurring.
© 2008 Elsevier B.V.
|
| 2 |
ALD of Copper and Copper Oxide Thin Films For Applications in Metallization Systems of ULSI DevicesWaechtler, Thomas, Oswald, Steffen, Roth, Nina, Lang, Heinrich, Schulz, Stefan E., Gessner, Thomas 15 July 2008 (has links) (PDF)
<p>
As a possible alternative for growing seed layers
required for electrochemical Cu deposition of
metallization systems in ULSI circuits,
the atomic layer deposition (ALD) of Cu is
under consideration. To avoid drawbacks related
to plasma-enhanced ALD (PEALD), thermal growth
of Cu has been proposed by two-step processes
forming copper oxide films by ALD which are
subsequently reduced.
</p>
<p>
This talk, given at the 8th International
Conference on Atomic Layer Deposition
(ALD 2008), held in Bruges, Belgium from
29 June to 2 July 2008, summarizes the results
of thermal ALD experiments from
[(<sup><i>n</i></sup>Bu<sub>3</sub>P)<sub>2</sub>Cu(acac)]
precursor and wet O<sub>2</sub>. The precursor is of particular
interest as it is a liquid at room temperature
and thus easier to handle than frequently
utilized solids such as Cu(acac)<sub>2</sub>,
Cu(hfac)<sub>2</sub> or
Cu(thd)<sub>2</sub>. Furthermore the substance is
non-fluorinated, which helps avoiding a major
source of adhesion issues repeatedly observed
in Cu CVD.
</p>
<p>
As result of the ALD experiments, we obtained composites of metallic and
oxidized Cu on Ta
and TaN, which was determined by
angle-resolved XPS analyses. While smooth,
adherent films were grown on TaN in an ALD
window up to about 130°C, cluster-formation due to
self-decomposition of the precursor was observed
on Ta. We also recognized a considerable
dependency of the growth on the degree of
nitridation of the TaN. In contrast, smooth
films could be grown up to 130°C on SiO<sub>2</sub>
and Ru, although in the latter case the ALD window
only extends to about 120°C. To apply the ALD
films as seed layers in subsequent electroplating
processes, several reduction processes are
under investigation. Thermal and plasma-assisted
hydrogen treatments are studied, as well as
thermal treatments in vapors of isopropanol,
formic acid, and aldehydes. So far these
attempts were most promising using formic
acid at temperatures between 100 and 120°C,
also offering the benefit of avoiding
agglomeration of the very thin ALD films on
Ta and TaN. In this respect, the process
sequence shows potential for depositing
ultra-thin, smooth Cu films at temperatures
below 150°C.
</p>
|
| 3 |
New Precursors for CVD Copper MetallizationNorman, John A. T., Perez, Melanie, Schulz, Stefan E., Waechtler, Thomas 02 October 2008 (has links)
A novel CVD copper process is described using
two new copper CVD precursors, KI3 and KI5, for
the fabrication of IC or TSV (Through Silicon Via)
copper interconnects. The highly conformal CVD
copper can provide seed layers for subsequent
copper electroplating or can be used to directly
fabricate the interconnect in one step. These
new precursors are thermally stable yet chemically
reactive under CVD conditions, growing copper
films of exceptionally high purity at high growth
rates. Their thermal stability can allow for
elevated evaporation temperatures to generate
the high precursor vapor pressures needed for
deep penetration into high aspect ratio TSV vias.
Using formic acid vapor as a reducing gas with
KI5, copper films of > 99.99 atomic % purity
were grown at 250°C on titanium nitride at a
growth rate of > 1500 Å/min. Using
tantalum
nitride coated TSV type wafers, ~ 1700 Å of
highly conformal copper was grown at 225°C into
32 μm × 5 μm trenches with good adhesion. With
ruthenium barriers we were able to grow copper
at 125°C at a rate of 20 Å/min to give a
continuous ~ 300 Å copper film. In this respect,
rapid low temperature CVD copper growth offers
an alternative to the long cycle times associated
with copper ALD which can contribute to copper
agglomeration occurring.
© 2008 Elsevier B.V.
|
| 4 |
Detailed Study of Copper Oxide ALD on SiO2, TaN, and RuWaechtler, Thomas, Schulze, Steffen, Hofmann, Lutz, Hermann, Sascha, Roth, Nina, Schulz, Stefan E., Gessner, Thomas, Lang, Heinrich, Hietschold, Michael 10 August 2009 (has links) (PDF)
Copper films with a thickness in the nanometer
range are required as seed layers for the
electrochemical Cu deposition to form multilevel
interconnects in ultralarge-scale
integrated (ULSI) electronic devices.
Continuously shrinking device dimensions and
increasing aspect ratios of the dual-damascene
structures in the copper-based metallization
schemes put ever more stringent requirements on
the films with respect to their conformality in
nanostructures and thickness homogeneity across
large wafers. Due to its intrinsic self-limiting
film growth characteristic, atomic layer
deposition (ALD) appears
appropriate for
homogeneously coating complex substrates and to
replace conventional physical vapor deposition
(PVD) methods beyond the 32 nm technology node.
To overcome issues of direct Cu ALD, such as
film agglomeration at higher temperatures or
reduced step coverage in plasma-based processes,
an
ALD copper oxide film may be grown under mild
processing conditions, while a subsequent
reduction
step converts it to metallic copper. In this
poster, which was presented at the AVS 9th
International Conference on Atomic Layer
Deposition (ALD 2009), held in Monterey,
California from
19 to 22 July 2009, we
report detailed film growth studies of ALD
copper
oxide in the self-limiting regime on SiO2, TaN
and Ru. Applications in subsequent
electrochemical deposition processes are
discussed, comparing Cu plating results on
as-deposited
PVD Ru as well as with PVD and reduced ALD Cu
seed layer.
|
| 5 |
ALD-grown seed layers for electrochemical copper deposition integrated with different diffusion barrier systemsWaechtler, Thomas, Ding, Shao-Feng, Hofmann, Lutz, Mothes, Robert, Xie, Qi, Oswald, Steffen, Detavernier, Christophe, Schulz, Stefan E., Qu, Xin-Ping, Lang, Heinrich, Gessner, Thomas 18 May 2011 (has links) (PDF)
The deposition of Cu seed layers for electrochemical Cu deposition (ECD) via atomic layer deposition (ALD) of copper oxide and subsequent thermal reduction at temperatures between 110 and 120°C was studied on different diffusion barrier systems. While optimization of the process is required on TaN with respect to reduction and plating, promising results were obtained on blanket PVD Ru. The plating results on layers of ALD Cu with underlying Ru even outperformed the ones achieved on PVD Cu seed layers with respect to morphology and resistivity. Applying the processes to via and line patterns gave similar results, suggesting that a combination of ALD Cu with PVD or ALD-grown Ru could significantly improve the ECD Cu growth.
|
| 6 |
Detailed Study of Copper Oxide ALD on SiO2, TaN, and RuWaechtler, Thomas, Schulze, Steffen, Hofmann, Lutz, Hermann, Sascha, Roth, Nina, Schulz, Stefan E., Gessner, Thomas, Lang, Heinrich, Hietschold, Michael 10 August 2009 (has links)
Copper films with a thickness in the nanometer
range are required as seed layers for the
electrochemical Cu deposition to form multilevel
interconnects in ultralarge-scale
integrated (ULSI) electronic devices.
Continuously shrinking device dimensions and
increasing aspect ratios of the dual-damascene
structures in the copper-based metallization
schemes put ever more stringent requirements on
the films with respect to their conformality in
nanostructures and thickness homogeneity across
large wafers. Due to its intrinsic self-limiting
film growth characteristic, atomic layer
deposition (ALD) appears
appropriate for
homogeneously coating complex substrates and to
replace conventional physical vapor deposition
(PVD) methods beyond the 32 nm technology node.
To overcome issues of direct Cu ALD, such as
film agglomeration at higher temperatures or
reduced step coverage in plasma-based processes,
an
ALD copper oxide film may be grown under mild
processing conditions, while a subsequent
reduction
step converts it to metallic copper. In this
poster, which was presented at the AVS 9th
International Conference on Atomic Layer
Deposition (ALD 2009), held in Monterey,
California from
19 to 22 July 2009, we
report detailed film growth studies of ALD
copper
oxide in the self-limiting regime on SiO2, TaN
and Ru. Applications in subsequent
electrochemical deposition processes are
discussed, comparing Cu plating results on
as-deposited
PVD Ru as well as with PVD and reduced ALD Cu
seed layer.
|
| 7 |
ALD-grown seed layers for electrochemical copper deposition integrated with different diffusion barrier systemsWaechtler, Thomas, Ding, Shao-Feng, Hofmann, Lutz, Mothes, Robert, Xie, Qi, Oswald, Steffen, Detavernier, Christophe, Schulz, Stefan E., Qu, Xin-Ping, Lang, Heinrich, Gessner, Thomas January 2011 (has links)
The deposition of Cu seed layers for electrochemical Cu deposition (ECD) via atomic layer deposition (ALD) of copper oxide and subsequent thermal reduction at temperatures between 110 and 120°C was studied on different diffusion barrier systems. While optimization of the process is required on TaN with respect to reduction and plating, promising results were obtained on blanket PVD Ru. The plating results on layers of ALD Cu with underlying Ru even outperformed the ones achieved on PVD Cu seed layers with respect to morphology and resistivity. Applying the processes to via and line patterns gave similar results, suggesting that a combination of ALD Cu with PVD or ALD-grown Ru could significantly improve the ECD Cu growth.
|
| 8 |
ALD of Copper and Copper Oxide Thin Films For Applications in Metallization Systems of ULSI DevicesWaechtler, Thomas, Oswald, Steffen, Roth, Nina, Lang, Heinrich, Schulz, Stefan E., Gessner, Thomas 15 July 2008 (has links)
As a possible alternative for growing seed layers required for electrochemical Cu deposition of metallization systems in ULSI circuits, the atomic layer deposition (ALD) of Cu is under consideration. To avoid drawbacks related to plasma-enhanced ALD (PEALD), thermal growth of Cu has been proposed by two-step processes forming copper oxide films by ALD which are subsequently reduced.
This talk, given at the 8th International Conference on Atomic Layer Deposition (ALD 2008), held in Bruges, Belgium from 29 June to 2 July 2008, summarizes the results of thermal ALD experiments from [(<sup><i>n</i></sup>Bu<sub>3</sub>P)<sub>2</sub>Cu(acac)] precursor and wet O<sub>2</sub>. The precursor is of particular
interest as it is a liquid at room temperature and thus easier to handle than frequently utilized solids such as Cu(acac)<sub>2</sub>,
Cu(hfac)<sub>2</sub> or Cu(thd)<sub>2</sub>. Furthermore the substance is non-fluorinated, which helps avoiding a major source of adhesion issues repeatedly observed in Cu CVD.
As result of the ALD experiments, we obtained composites of metallic and oxidized Cu on Ta and TaN, which was determined by angle-resolved XPS analyses. While smooth, adherent films were grown on TaN in an ALD window up to about 130°C, cluster-formation due to self-decomposition of the precursor was observed on Ta. We also recognized a considerable dependency of the growth on the degree of nitridation of the TaN. In contrast, smooth films could be grown up to 130°C on SiO<sub>2</sub>and Ru, although in the latter case the ALD window only extends to about 120°C. To apply the ALD films as seed layers in subsequent electroplating processes, several reduction processes are
under investigation. Thermal and plasma-assisted hydrogen treatments are studied, as well as thermal treatments in vapors of isopropanol, formic acid, and aldehydes. So far these attempts were most promising using formic acid at temperatures between 100 and 120°C, also offering the benefit of avoiding agglomeration of the very thin ALD films on
Ta and TaN. In this respect, the process sequence shows potential for depositing ultra-thin, smooth Cu films at temperatures below 150°C.
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