Formation of Cu diffusion channels in Ta layer of a Cu/Ta/SiO[sub 2]/Si structure

Li, S.; Dong, Z. L.; Latt, K. Maung; Park, H. S.; White, T.
April 2002
Applied Physics Letters;4/1/2002, Vol. 80 Issue 13, p2296
Academic Journal
Three mechanisms for the formation of Cu diffusion channels in the Ta layer of a Cu/Ta/SiO[sub 2]/Si structure are proposed. First, it is suggested that stacking faults formed during the recovery process induce localized regions of high internal energy in the Ta layer, from which Cu channels originate. Second, chemical reaction occurs at 800 °C and forms Ta[sub 4]CuO[sub 11] across the Cu/Ta interface in Cu and Ta layers, which opens up channels for Cu diffusion. Third, triple junctions at the grain boundary of the Cu and Cu/Ta interface provide sites for the initiation of channel formation at 800 °C. At 950 °C, these channels in the diffusion barrier are absent, but Ta was oxidized into disordered Ta[sub 2]O[sub 5] that may contain pathways for Cu diffusion.


Related Articles

  • External Copper Inhibits the Activity of the Large-Conductance Calcium- and Voltage-sensitive Potassium Channel from Skeletal Muscle. Morera, F. J.; Wolff, D.; Vergara, C. // Journal of Membrane Biology;Mar2003, Vol. 192 Issue 1, p65 

    We have characterized the effect of external copper on the gating properties of the large-conductance calcium- and voltage-sensitive potassium channel from skeletal muscle, incorporated into artificial bilayers. The effect of Cu2+ was evaluated as changes in the gating kinetic properties of the...

  • Tantalum-microcystalline CeO2 diffusion barrier for cooper metallization. Yoon, Dong-Soo; Baik, Hong Koo; Lee, Sung-Man // Journal of Applied Physics;2/1/1998, Vol. 83 Issue 3, p1333 

    Proposes a tantalum diffusion barrier incorporating microcrystalline CeO2 for copper (Cu) metallization. Information on the investigation conducted on the barrier; Detailed information on the experiments conducted; Results of this study.

  • Effect of thin V insertion layer into Ta film on the performance of Ta diffusion barrier in Cu... Kwak, Joon Seop; Baik, Hong Koo // Journal of Applied Physics;5/1/1999, Vol. 85 Issue 9, p6898 

    Focuses on a study which investigated the effect of a thin vanadium (V) insertion layer into tantalum (Ta) with or without ion bombardment on Ta diffusion barrier performance in copper metallization. Reason copper has attracted attention as an interconnection material; Use of x-ray diffraction...

  • Tantalum as a diffusion barrier between copper and silicon. Holloway, Karen; Fryer, Peter M. // Applied Physics Letters;10/22/1990, Vol. 57 Issue 17, p1736 

    We have investigated the effectiveness and failure mechanism of thin tantalum layers as diffusion barriers to copper. 50 nm tantalum films were sputtered onto unpatterned single-crystal <100> Si wafers and overlaid with 100 nm Cu. Material reactions in these films were followed as a function of...

  • Increasing coercivity of CoCrTaPt/Cr thin film media by interdiffusion of Mn... Peng, Wenbin // Journal of Applied Physics;4/15/1999 Part 2A of 2, Vol. 85 Issue 8, p4702 

    Studies manganese and copper overlayers with cobaltchromiumtantalumplatinum/chromium (CoCrTaPt/Cr) films on glass substrates. Experimental details; Results and discussion; Conclusions.

  • An optimal quasisuperlattice design to further improve thermal stability of tantalum nitride diffusion barriers. Chen, G. S.; Huang, S. C.; Chen, S. T.; Yang, T. J.; Lee, P. Y.; Jou, J. H.; Lin, T. C. // Applied Physics Letters;5/15/2000, Vol. 76 Issue 20 

    X-ray diffraction and transmission electron microscopy, along with electrical and film stress measurements, were used to evaluate the effectiveness of 40-nm-thick amorphous Ta[sub 2]N and microcrystalline TaN diffusion barriers, both single and multilayered, against Cu penetration. Failure of...

  • Copper wetting of a tantalum silicate surface: Implications for interconnect technology. Zhao, X.; Leavy, M.; Magtoto, N. P.; Kelber, J. A. // Applied Physics Letters;11/19/2001, Vol. 79 Issue 21, p3479 

    X-ray photoelectron spectroscopy data show that sputter-deposited Cu (300 K) displays conformal growth on oxidized TaSi films (TaSiO[sub 6]). The TaSiO[sub 6] films, 6 Ã… thick, were formed by sputter deposition of Ta onto ultrathin SiO[sub 2] substrates at 300 K, followed by annealing to 600...

  • Tantalum-based diffusion barriers in Si/Cu VLSI metallizations. Kolawa, E.; Chen, J. S.; Reid, J. S.; Pokela, P. J.; Nicolet, M.-A. // Journal of Applied Physics;8/1/1991, Vol. 70 Issue 3, p1369 

    Presents a study that investigated tantalum-based diffusion barriers in silicon/copper VLSI metallizations. Experimental procedures; Results and discussion; Conclusion.

  • Secondary ion mass spectrometry study of the thermal stability of Cu/refractory metal/Si structures. Lane, L. C.; Nason, T. C.; Yang, G.-R.; Lu, T.-M.; Bakhru, H. // Journal of Applied Physics;5/1/1991, Vol. 69 Issue 9, p6719 

    Presents a study that presented evidence for the blocking of copper diffusion into silicon dioxide and silicon by tantalum (Ta) and Ta/tungsten barriers. Capacity of a chromium layer as thin as 200 A; Versatility of secondary ion mass spectrometry; Requirement for metallization.


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics