CCl₂F₂プラズマによるCu/Cr薄膜の化学変化

抄録

An attempt was made to etch Cu/Cr thin films by CCl₂F₂ plasma using an L-coupled reactor. Nonvolatile CuCI was found to appear on the surface of the films. The formation of CuCl is the result of a plasma reaction taking place along the grain boundaries. A mass-spectroscopic analysis suggests that the plasma reaction is due to the presence of CF₃⁺ ions. The Cr layer under the Cu one was occasionally found to diffuse onto the surface of the Cu layer during the plasma reaction. The process of the Cr diffusion is probably due to the sinking phenomena observed in Au/Si structure in air, i.e. the out-diffusion of Cr through Cu thin films in CCl₂F₂ plasma.