Methods of fabricating semiconductor devices having conductive pad structures with multi-barrier films

A method of fabricating a semiconductor device, comprising:

• forming an interconnect structure over a substrate, wherein the interconnect structure comprises a copper layer;
• depositing a crystalline tantalum-nitride (TaN) film in contact with the copper layer;
• depositing an amorphous tantalum-nitride (TaN) film over the crystalline TaN film;
• depositing an aluminum-containing layer over the amorphous TaN film;
• and
• patterning the aluminum-containing layer, the amorphous TaN film and the crystalline TaN film to form a conductive pad structure.

A method of fabricating a semiconductor device, comprising:

• forming an interconnect structure over a substrate, wherein the interconnect structure is electrically coupled to electronic elements in the substrate;
• and
• forming a conductive pad structure in contact with the interconnect structure, comprising:
• forming a lower tantalum-nitride (TaN) film using a first deposition process with a first level of power;
• forming an upper tantalum-nitride (TaN) film over the lower TaN film using a second deposition process with a second level of power that is different from the first level of power, wherein the upper TaN film has a nitrogen atomic percentage that is higher than a nitrogen atomic percentage of the lower TaN film;
• forming an aluminum-containing layer over the upper TaN film;
• and
• patterning the aluminum-containing layer, the upper TaN film, and the lower TaN layer.