Plasma-etching induced damage in thin oxide

It is pointed out that plasma Al etching and resist ashing processes cause Fowler-Nordheim current to flow through the oxide and that plasma-induced damage can be simulated and modeled as damage produced by constant current electrical stress. The current produced by the plasma process increases with the antenna size of the device structure. C-V measurement is a more sensitive technique for characterizing plasma-etching-induced damage than oxide breakdown. The stress current is collected only through the aluminum surfaces not covered by the photoresist during plasma processes. The plasma stress current is proportional to Al pad peripheral length during Al etching and Al pad area during photoresist stripping. A model of oxide damage due to plasma etching is proposed.<
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