Contribution a l’etude de l’influence des couches barrieres sur le phenomene de diffusion a l’interface metal/silicium pour des couches minces formees par evaporation par effet joule: Cas du systeme : CU/SB/SI (100), CU/SB/SI (110), CU/SB/SI (111).

Abstract

In this work, the solid-state reaction between a copper thin film of thickness 575Å and another of antimony of thickness 300 Å deposited by thermal evaporation over a silicon substrate Si (100), (110) and (111), have been studied using X-ray diffraction, scanning electron microscopy and Rutherford backscattering. The samples were heat treated in vacuum at temperature range 200-400°C for 45 minutes. The results show the growth and the formation of Cu3Sb in the different interfaces Cu/Sb/Si at 200°C and at 400°C.We notice also the apparition of the copper silicides pics Cu5Si, Cu0.83Si0.17 and Cu4Si and Cu3Si at 400°C, which indicates a diffusion of copper atoms in the silicon substrates through the barrier layer of antimony for this temperature. The heat treatment of the samples at 400 °C generates the stability of the Cu3Sb, Cu2Sb and Cu11Sb3 components. The Cu3.3Sb phase appears in all orientations of the substrates.