Reduced Cu interface diffusion by CoWP surface coating

Hu, C.‐K.; Gignac, Lynne; Rosenberg, R.; Liniger, E.; Rubino, J. Germán; Sambucetti, C.J.; Stamper, A. K.; Domenicucci, A.; Chen, X.

doi:10.1016/s0167-9317(03)00286-7

Cited by 107 publications

(51 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such efforts include the insertion of a thin layer of CoWP between Cu and the passivation layer , Hu 2003a, Hu 2003b, Hu 2004, as well as alloying Cu with small percentages of aluminum . While these studies focus on reducing interfacial mass transport to improve the lifetime and possibly the activation energy, a better understanding of sigma is still needed.…”

Section: Timementioning

confidence: 99%

“…Most research efforts to increase EM reliability have focused on slowing mass transport at the top interface to extend the median lifetime , Meyer 2002, Hu 2003a, Hu 2003b, Hu 2004 It is clear that the median time-to-failure as well as the activation energy of the diffusion process depend directly on the EM mass transport mechanism. Thus, improving the top interface which serves as the major diffusion path appears to be the most promising approach to enhance EM performance with regard to these parameters.…”

Section: Recent Em Improvementsmentioning

confidence: 99%

“…, Hu 2003a, Hu 2003b, Hu 2004. The major focus of these studies is the effect of an interface change on the EM mass transport mechanism.…”

Section: Influence Of Passivation Layermentioning

confidence: 99%

See 2 more Smart Citations

Statistical Analysis of Electromigration Lifetimes and Void Evolution for Cu Interconnects

Hauschildt

Gall²,

Thrasher³

et al. 2004

MRS Proc.

View full text Add to dashboard Cite

Electromigration (EM) failure statistics and the origin of the lognormal deviation (σ) for Cu interconnects have been investigated by analyzing the lifetime statistics and void size distributions at various stages during EM testing. Experiments were performed on 0.18 μm wide Cu interconnects with tests terminated after specific amounts of resistance increases, or after a specified test time. Void size distributions of resistance-based, as well as time-based EM tests were obtained using focused ion beam (FIB) microscopy. The lifetime and void size distributions were found to follow lognormal distribution functions. The σ values of EM lifetime and time-based void size distributions decrease with higher percentages of resistance increase, reaching an asymptotic value of σ ∼ 0.14. In contrast, σ values of resistance-based void size distributions are significantly smaller and do not show an obvious dependence on time. The statistics of resistance-based void size distributions can mainly be accounted for by geometrical variations of the void shape, while the statistics of time-based void size distributions requires consideration of kinetic aspects of the EM process. The σ values of EM lifetime distributions at long times can be simulated based on measured void size distributions, taking into account geometrical and experimental factors of EM. In contrast, for short times the statistics of initial void formation and the kinetics of interfacial mass transport have to be considered.

show abstract

Section: Timementioning

confidence: 99%

Section: Recent Em Improvementsmentioning

confidence: 99%

See 1 more Smart Citation

Statistical Analysis of Electromigration Lifetimes and Void Evolution for Cu Interconnects

Hauschildt

Gall²,

Thrasher³

et al. 2004

MRS Proc.

View full text Add to dashboard Cite

show abstract

“…Lee 21 also pointed out that the presence of W and P in the electroless CoWP film can affect its diffusion barrier property against copper. Additionally, the electroless CoWP film significantly improves the electromigration lifetime of Cu interconnects by providing protection against interface diffusion of Cu, as has been confirmed by the studies of Hu et al 22,23 These investigations show that electroless CoWP possesses excellent inhibition of Cu diffusion and that it is worth carrying out detailed studies of the performance of electroless CoWP in Cu metallization.…”

Section: Introductionmentioning

confidence: 64%

Electroless CoWP as a Diffusion Barrier between Electroless Copper and Silicon

Tsai

Liu

et al. 2007

Journal of Elec Materi

View full text Add to dashboard Cite

In this work, an electroless CoWP film deposited on a silicon substrate as a diffusion barrier for electroless Cu and silicon has been studied. Four different Cu 120 nm/CoWP/Si stacked samples with 30, 60, 75, and 100 nm electroless CoWP films were prepared and annealed in a rapid thermal annealing (RTA) furnace at 300°C to 800°C for 5 min. The failure behavior of the electroless CoWP film in the Cu/CoWP/Si sample and the effect of CoWP film thickness on the diffusion barrier properties have been investigated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and sheet resistance measurements. The composition of the electroless CoWP films was 89.4 at.% Co, 2.4 at.% W, and 8.2 at.% P, as determined by energy dispersive X-ray spectrometer (EDS). A 30 nm electroless CoWP film can prevent copper penetration up to 500°C, and a 75 nm electroless CoWP film can survive at least up to 600°C. Therefore, increasing the thickness of electroless CoWP films effectively increases the failure temperature of the Cu/CoWP/Si samples. The observations of SEM and TEM show that interdiffusion of the copper and cobalt causes the failure of the electroless CoWP diffusion barriers in Cu/CoWP/Si during thermal annealing.

show abstract

“…Among them, CoWP layer has been found very promising because of its better barrier capability and performance at higher temperature [10,[12][13][14]. There are some reports on the fabrication of CoWP barrier/capping layers by electroless deposition [15][16][17][18][19][20][21][22].…”

Section: Introductionmentioning

confidence: 99%