As the technology of semiconductor devices continues to evolve to smaller geometries and increased circuit densities, it has become necessary to rely upon Reactive Ion Etch techniques for final pattern definition. For this study, a metal stack of TiW/AlCu/TiW is ECR etched, generating a polymer which can be characterized as follows: both carbon and nitrogen are present due to residual photoresist components; and trace amounts of TiW and Cu are present due to back-sputtering during ECR. Together the representative elements comprise an organo-metallic polymer. After ECR etching, the organo-metallic polymer is subjected to increased cycle times of in-situ microwave ashing. As the cycle times increase, the amount of inorganic residue increase proportionally, and is measured as the amount of elemental oxygen present on the substrate surface.
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