METHOD FOR FORMING A COPPER BASED METAL PATTERN

摘要

A composite mask (5A, 6A) is formed by sequentially depositing blanket layers (5) and (6) of molybdenum and of a material respectively selected from the group consisting of MgO and Al2O3 on the surface of a copper layer (3), and producing in these layers (5) and (6) a pattern of openings corresponding to the negative of the desired copper pattern (3). Using said mask (5A, 6A) the portions of copper layer (3) exposed in said openings are removed, preferably by dry etching. MgO or Al2O3 adhere well to Mo and Mo adheres well to copper. The Mo layer (5A) also serves as a diffusion barrier for the copper. …The method is applicable in forming copper interconnect metallurgy for components such as semiconductor or dielectric substrates.