Enhanced growth and Cu diffusion barrier properties of thermal ALD TaNC films in Cu/low-k interconnects

Wojcik, H.; Hoßbach, Christoph; Kubasch, C.; Verdonck, Patrick; Barbarin, Y.; Merkel, U.; Bartha, Johann W.; Hübner, René; Engelmann, Hans‐Jürgen; Friedemann, M.

doi:10.1016/j.mee.2013.03.176

Cited by 5 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One such challenge relates to connectivity -most circuitry relies on copper (Cu) as the key element due to its low resistivity and high electromigration resistance. However, in the "transistor scaling" revolution, Cu becomes much more resistive when its dimension is scaled down, and Cu diffusion barriers such as tantalum nitride/tantalum (TaN/Ta) fail at thicknesses below 4nm [3,4] . Thus, new materials and back-end-of-line (BEOL) compatible synthesis methods are urgently needed.…”

Section: Introductionmentioning

confidence: 99%

Incorporating Niobium in MoS₂ at BEOL‐Compatible Temperatures and its Impact on Copper Diffusion Barrier Performance

Zhao

Zhang

et al. 2019

Adv Materials Inter

View full text Add to dashboard Cite

The continuous scaling of transistors has led to unprecedented challenges for interconnect technologies. Conventional barriers fail when thinned below 4nm, therefore novel materials and back-end-of-line (BEOL) compatible synthesis are urgently needed. Two-dimensional transition metal dichalcogenides (2D-TMDs) present a unique opportunity for addressing the scaling of interconnects. Here, nanometer thick Nb-incorporated MoS 2 is successfully synthesized at BEOL compatible temperatures and their abilities of blocking Cu atom diffusion have been investigated. We have systematically studied Nb incorporation of MoS 2 at 450°C and compared its growth dynamics with those carried out at high temperatures. The addition of a few percent Nb in MoS 2 enhances breakdown time by more than 100x, reaching a failure time >12500s under the electric field of 7MV/cm. These results suggest that integration of Nb-incorporated MoS 2 in electronic technologies is a promising route for the sub-5nm technology node.

show abstract

Section: Introductionmentioning

confidence: 99%

Incorporating Niobium in MoS₂ at BEOL‐Compatible Temperatures and its Impact on Copper Diffusion Barrier Performance

Zhao

Zhang

et al. 2019

Adv Materials Inter

View full text Add to dashboard Cite

show abstract

“…These single element diffusion barriers include Ta, W, Ni, Cr, Ti, Nb, Co, and Mo. Refractory materials for diffusion barriers have gained acceptance due to their high‐temperature stability and low chemical reactivity, and include TaC, WNx, HfNx, TaSi, TaN, TiN, and TiON …”

Section: Current State Of the Art In Diffusion Barriers For Microelecmentioning

confidence: 99%

“…In addition, chemical compositions of the diffusion barriers can be tailored to adjust material properties by adjusting the precursor chemistry. ALD has been used to create new compounds of low‐dimensional films (<3 nm), including MnO x , Ta x N y C z , Co–W, V–N, and Mn–Ru …”

Section: Current State Of the Art In Diffusion Barriers For Microelecmentioning

confidence: 99%

“…Copper is not only a fast diffuser in silicon and SiO 2 , but it forms low‐temperature silicides and midgap traps, recombination centers, and reduces minority carrier lifetimes . Many investigations have been carried out using various metals and compounds to prevent copper from diffusing into silicon or SiO 2 . These single element diffusion barriers include Ta, W, Ni, Cr, Ti, Nb, Co, and Mo.…”

Section: Current State Of the Art In Diffusion Barriers For Microelecmentioning

confidence: 99%

See 1 more Smart Citation

Review of Graphene as a Solid State Diffusion Barrier

Morrow

Pearton

Ren

2015

Small

View full text Add to dashboard Cite

Conventional thin-film diffusion barriers consist of 3D bulk films with high chemical and thermal stability. The purpose of the barrier material is to prevent intermixing or penetration from the two materials that encase it. Adhesion to both top and bottom materials is critical to the success of the barrier. Here, the effectiveness of a single atomic layer of graphene as a solid-state diffusion barrier for common metal schemes used in microelectronics is reviewed, and specific examples are discussed. Initial studies of electrical contacts to graphene show a distinct separation in behavior between metallic groups that strongly or weakly bond to it. The two basic classes of metal reactions with graphene are either physisorbed metals, which bond weakly with graphene, or chemisorbed metals, which bond strongly to graphene. For graphene diffusion barrier testing on Si substrates, an effective barrier can be achieved through the formation of a carbide layer with metals that are chemisorbed. For physisorbed metals, the barrier failure mechanism is loss of adhesion at the metal–graphene interface. A graphene layer encased between two metal layers, in certain cases, can increase the binding energy of both films with graphene, however, certain combinations of metal films are detrimental to the bonding with graphene. While the prospects for graphene's future as a solid-state diffusion barrier are positive, there are open questions, and areas for future research are discussed. A better understanding of the mechanisms which influence graphene's ability to be an effective diffusion barrier in microelectronic applications is required, and additional experiments are needed on a broader range of metals, as well as common metal stack contact structures used in microelectronic applications. The role of defects in the graphene is also a key area, since they will probably influence the barrier properties.

show abstract

“…In the LSI generation below the 32 nm technology, the atomic layer deposition (ALD) method for ultrathin layers was developed to meet the requirement for thin barriers. [4][5][6][7][8] However, the ALD barrier has two fatal problems: the extremely weak adhesion, 9,10) which causes peeling off during the subsequent processes, and an extremely high resistivity, 5,[11][12][13][14] which gives rise to difficulties. Thus, there is now a poor prospect of a good solution to realizing an ultrathin barrier of low resistivity.…”

Section: Introductionmentioning

confidence: 99%

Barrier properties of ultrathin VN films of low resistivity and high density for Cu interconnects

Takeyama

Sato

Itoi

et al. 2016

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

We have examined vanadium nitride (VN) films as a candidate material for the low-resistivity diffusion barrier of Cu interconnects in Si-LSI technology, aimed at reducing the interconnect resistance. We successfully prepared a continuous and uniform VN film as thin as 5 nm with a nanocrystalline texture with grains 2–5 nm in size. The VN barrier applied to the model system of Cu/VN/SiO2/Si and Cu/VN/SiOC/Si shows excellent barrier properties; the ultrathin barrier shows a negligible structural change and the absence of Cu penetration and/or interfacial reaction in the systems after annealing at 500 °C. The properties of an ultrathin VN barrier, such as low resistivity (50 µΩ cm) and high density (5.8 g/cm3), are attributed to the formation of a stable δ-VN phase in a nanocrystalline texture with grains of size smaller than or equal to the barrier thickness that stands high in a structurally stable and chemically inert barrier.

show abstract

Enhanced growth and Cu diffusion barrier properties of thermal ALD TaNC films in Cu/low-k interconnects

Cited by 5 publications

References 8 publications

Incorporating Niobium in MoS₂ at BEOL‐Compatible Temperatures and its Impact on Copper Diffusion Barrier Performance

Incorporating Niobium in MoS₂ at BEOL‐Compatible Temperatures and its Impact on Copper Diffusion Barrier Performance

Review of Graphene as a Solid State Diffusion Barrier

Barrier properties of ultrathin VN films of low resistivity and high density for Cu interconnects

Contact Info

Product

Resources

About

Enhanced growth and Cu diffusion barrier properties of thermal ALD TaNC films in Cu/low-k interconnects

Cited by 5 publications

References 8 publications

Incorporating Niobium in MoS2 at BEOL‐Compatible Temperatures and its Impact on Copper Diffusion Barrier Performance

Incorporating Niobium in MoS2 at BEOL‐Compatible Temperatures and its Impact on Copper Diffusion Barrier Performance

Review of Graphene as a Solid State Diffusion Barrier

Barrier properties of ultrathin VN films of low resistivity and high density for Cu interconnects

Contact Info

Product

Resources

About

Incorporating Niobium in MoS₂ at BEOL‐Compatible Temperatures and its Impact on Copper Diffusion Barrier Performance

Incorporating Niobium in MoS₂ at BEOL‐Compatible Temperatures and its Impact on Copper Diffusion Barrier Performance