PREPARATION OF CU10ZR7 INTERMETALLIC COMPOUND FILM AND ITS APPLICATION AS A DIFFUSION BARRIER IN CU CU10ZR7/ZRN/SI CONTACT SYSTEM/

We investigated the diffusion barrier properties of Cu10Zr7 intermetal lic compound film for possible application to Cu metallization technol ogy, First, a Cu/Zr bilayered film was heat-treated in vacuum at vario us temperatures for 1h, to confirm the most stable Cu-Zr compound form ed by solid-phase reaction. it was found that a single phase of Cu10Zr 7 compound can be obtained at temperatures above 550 degrees C and tha t this compound film is stable up to 600 degrees C. On the other hand, by the co-sputtering method, although CuZr2-Cu10Zr7 mixture alloy fil m was prepared, no Cu10Zr7 single-phase compound film was obtained. We heat-treated the Cu/CuZr2-Cu10Zr7 bilayered film for 2h at 500 degree s C, which was lower than the temperature necessary for the formation of Cu10Zr7 by solid-phase reaction. In this way, we prepared the stoic hiometric Cu10Zr7 film. Then: we produced the Cu/Cu10Zr7/ZrN/Si contac t system using this CU10Zr7 film as a diffusion barrier and investigat ed its thermal stability. We found that the sz stem is satisfactorily stable up to 650 degrees C without any Si diffusion, although a slight diffusion of Cu was observed at the interface of Cu/Cu10Zr7.