For copper/low-dielectric constant ͑low-k͒ interconnects, delamination at the dielectric-barrier metal interface has been studied. In particular, the role of deposited etch polymers used for sidewall passivation on the integrity of this interface has been examined. We found that etch polymers were deposited on the flat ͑horizontal͒ surfaces used as low-k masks. Fluorinated polymeric etch residues of approximately 10-20 Å in thickness were detected using time-of-flight secondary ion mass spectroscopy and Auger electron spectroscopy. Although these etch residues resulted primarily from the etch sidewall passivation process, no detectable residue was found on the sidewalls themselves. The presence of the polymeric residue was found to compromise the integrity of the dielectric-barrier metal interface. Removal of the residue could be accomplished through either sputtering or by a concluding O 2 plasma flash step during etch. Using these techniques, significant improvement in dielectric-barrier metal interfacial integrity could be obtained.

Silicones derive many of their most useful properties from the inorganic nature of the silicon-to-oxygen links which they possess in common with glass and mineral silicates. They derive plasticity, solubility, and water repellency from the organic radicals attached to their basic structures. The chemical nature of silicon in combination with oxygen permits the development of a variety of silicone compounds in various physical forms ranging from fluids through gels and resins to elastic materials. Because of their ease of application, their general heat stability, and chemical inertness, they are natural complements to ceramic bodies in many applications. They are already proving their usefulness with these materials in the production of new types of electrical insulation, in the surface treatment of glass and ceramic products, and as auxiliary dielectrics for use with ceramic insulating forms.

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