Single-Oriented Growth of (111) Cu Film on Thin ZrN/Zr Bilayered Film for ULSI Metallization

We investigated the influence of ZrN/Zr bilayered film thickness on the (111) Cu orientation and the thermal stability of the Cu/ZrN/Zr/Si contact system by X-ray diffraction and Auger electron spectroscopy analyses. We confirmed that the single-oriented growth of (111) Cu can be realized by interposing the ZrN (400 Å)/Zr (200 Å) bilayered film between Cu and Si. It was revealed that the (111) Cu/(111) ZrN/(002) Zr/(001) Si contact system is satisfactorily stable up to 600°C without undesirable interfacial reaction and interdiffusion, maintaining the low contact resistivity of the ZrSi2 adhesion layer at the Si interface and the single-oriented state of the (111) Cu overlayer.