The energy-dispersive X-ray based permeation and oxidation test was further developed by an improved theoretical analysis, in which chemical potential gradients rather than concentration gradients were employed. The developed test was able to characterize diffusion kinetics in diffusion barriers at the nanometer scale. The Cu flux coefficient in (Cu,Ni)3Sn intermetallic compound nanolayers was determined from the test to be 8.48  x 10−15 mol/(msJ/mol) exp[−52.3(kJ/mol)/RT] at 250 to 400C.

Cu Diffusion Kinetics in (Cu,Ni)3Sn Intermetallic Compound Nanolayers Investigated by an Energy-Dispersive-X-ray-Based Permeation Test. L.Liu, H.Huang, R.Fu, D.Liu, T.Y.Zhang: Thin Solid Films, 2009, 518[1], 201-5