Copper diffusion in thin In_2S_3 layers investigated by Rutherford Backscattering Spectroscopy

摘要

Copper diffusion in thin In_2S_3 layers was investigated by measuring copper concentration profiles with Rutherford Backscattering Spectroscopy (RBS). For this purpose In_2S_3 layers (thickness 100 nm) were evaporated on crystalline silicon substrates and Cu was diffused from a CuSCN surface layer at temperatures between 150 and 250 ℃. The CuSCN source layer was removed in pyridine solution before RBS measurements were performed. Diffusion coefficients of Cu in In_2S_3 were obtained by simulating the diffusion process in a one-dimensional model and comparing measured and simulated Cu concentration profiles. The values of the exponential prefactor of the diffusion coefficient and of the activation energy were 9×10~(-11) cm~2/s and 0.3 eV, respectively.