Co capping layers for Cu/low-k interconnects

Yang, Chih‐Chao; Flaitz, P.; Li, B.; Chen, F.; Christiansen, C.; Lee, S. Y.; Ma, P.; Edelstein, D.

doi:10.1016/j.mee.2011.04.017

Cited by 17 publications

(7 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, Ohsita and Watanabe 2,5) showed in their PECVD experiment that Ti film did not deposit on SiO 2 surface where plasma was not irradiated while Ti deposited on Si surface forming TiSi x . They explained TiCl x would desorb from SiO 2 surface before reacting with H. Similar selective deposition natures were found in W 44) and Co 45) CVDs. Those metals deposit on Si and Cu, respectively, but not on dielectrics.…”

Section: Multiscale Simulation Modelsupporting

confidence: 61%

Multiscale plasma and feature profile simulations of plasma-enhanced chemical vapor deposition and atomic layer deposition processes for titanium thin film fabrication

Denpoh

Moroz

Kato

et al. 2020

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

Mechanisms of titanium (Ti) thin films deposited in plasma-enhanced (PE) chemical vapor deposition (CVD) and atomic layer deposition (ALD) processes have been elucidated via multiscale plasma and feature profile simulations. Firstly, by iterating a 2D reactor-scale plasma simulation and a feature-scale deposition profile simulation, a shared surface reaction model has been determined for PECVD processes. Ti film thicknesses and profiles consistently computed both along a wafer surface and inside a test structure agreed very well with the experimental data. Then, another multiscale simulation, with the same plasma model and the surface reaction model to which the Eley-Rideal surface kinetics is added, has been applied to a PEALD process. The simulation succeeded again in reproducing and explaining the non-conformal Ti film deposition observed in experiments, while conformal Ti films are obtained in PECVD processes. Through the simulation work, comprehensive mechanisms of Ti film deposition, which cover both PECVD and PEALD processes, have been discussed and proposed in this study.

show abstract

Section: Multiscale Simulation Modelsupporting

confidence: 61%

Multiscale plasma and feature profile simulations of plasma-enhanced chemical vapor deposition and atomic layer deposition processes for titanium thin film fabrication

Denpoh

Moroz

Kato

et al. 2020

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…5) Thereafter, the failure at the interface between the dielectric cap and Cu due to poor adhesion is drastically improved. As materials applicable to a metal cap, CoWP and related alloy films formed by electroless plating with Pd activation or self-activation, [5][6][7][8][9][10][11][12] such as Co films formed by chemical vapor deposition, 13,14) are examined. However, there are concerns about the oxidation resistance of Co and the thickness control of plating films in a thin region.…”

Section: Introductionmentioning

confidence: 99%

Application of Al–Nb alloy film to metal capping layer on Cu

Takeyama

Noya

2016

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

An Al–Nb alloy film with the Al72Nb28 composition is applied as a candidate metal capping layer on Cu interconnects. In the Al72Nb28/Cu/SiO2/Si model system, the preferential oxidation of Al forming a thin surface Al2O3 layer occurs owing to oxidation in air for 1 h at temperatures up to ∼300 °C, resulting in the protection of the layers underneath from further oxidation, although a slight Cu intermixing into Al–Nb occurs. With increasing oxidation temperature up to 500 °C, the surface Al2O3 layer still grows by the preferential oxidation of Al and rejects Cu atoms from the surface oxidized layer. Although Nb atoms are left behind in the surface oxidized layer, they are in a metallic state owing to the high solubility of oxygen before forming an oxide. The extremely low solubility of Nb in Cu also protects Cu without excess intermixing. A good passivation characteristic of the Al72Nb28 alloy film on Cu is demonstrated.

show abstract

“…Although the interface between Co(W) and Cu is contaminated by ligands or byproducts of CVD-Cu precursors, the adhesion strength is sufficient with regard to a reliable EM/SIV lifetime, as is the case for electroless-plated Co-based films. [37][38][39][40] The barrier properties and nanostructure of Co(W) films, however, is dependent on the precursors used.…”

mentioning

confidence: 99%

Self-Assembled Nano-Stuffing Structure in CVD and ALD Co(W) Films as a Single-Layered Barrier/Liner for Future Cu-Interconnects

Shimizu

Kumamoto

Shima

et al. 2013

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Cobalt film with tungsten [Co(W)] has the potential to be an effective single-layered barrier/liner in interconnects, due to its good adhesion with Cu, low resistivity compared with TaN, and comparable barrier properties to TaN. To reduce the resistivity of Co(W), oxygen-free Co(W) was fabricated from oxygen-free precursors, bis(N-tert-butyl-N′-ethylpropionamidinato) cobalt and bis(tert-butylimino)bis(dimethylamino) tungsten, by chemical vapor deposition (CVD) and atomic layer deposition (ALD). Our results showed that W addition improved the barrier properties of both CVD-Co(W) and ALD-Co(W) against Cu diffusion. The diffusion coefficient of Cu in Co(W) was reduced by W addition. The activation energy of Cu in CVD-Co(W) and ALD-Co(W) was 1.5 eV and 1.7–1.8 eV, respectively; whereas that in CVD-Co was 1.0 eV. Improvement in the barrier properties of Co(W) was attributed to the amorphous-like structure created by W. High-resolution transmission electron microscopy and multivariate spectral analysis of the nanoscale properties of Co(W) revealed that the improvement in the barrier properties was due to the self-assembled segregation of W atoms at the grain boundary. The segregated W atoms in both CVD-Co(W) and ALD-Co(W) films may act as a stuffing material. These results suggest Co(W), especially ALD-Co(W), as a promising material for Cu-interconnects in future ultra-large-scale integrated circuits.

show abstract

Co capping layers for Cu/low-k interconnects

Cited by 17 publications

References 1 publication

Multiscale plasma and feature profile simulations of plasma-enhanced chemical vapor deposition and atomic layer deposition processes for titanium thin film fabrication

Multiscale plasma and feature profile simulations of plasma-enhanced chemical vapor deposition and atomic layer deposition processes for titanium thin film fabrication

Application of Al–Nb alloy film to metal capping layer on Cu

Self-Assembled Nano-Stuffing Structure in CVD and ALD Co(W) Films as a Single-Layered Barrier/Liner for Future Cu-Interconnects

Contact Info

Product

Resources

About