S. W. Loh, D. H. Zhang, C. Y. Li, R. Liu, A. T. S. Wee, K. Prasad, C. M. Tan, Y. K. Lee, P. D. Foo, and J. Xie. “Effects of a thin flash layer on the diffusion of Cu, Ta, Si, and O in the Cu/TaN/SiO2/Si structures,” in Int. Semiconductor Technology Conf., 2001, pp. 116-122.