Thin oxide damage by plasma etching and ashing processes

In the study reported, the plasma Al etching and resist ashing processes caused Fowler-Nordheim current to flow through the oxide. The stress current was collected only through the aluminum surfaces not covered by the photoresist during the plasma processes. The plasma stress current was proportional to the Al pad peripheral length during Al etching and the Al pad area during photoresist stripping. Using the measured stress current, the breakdown voltage distribution of oxides after plasma processes can be predicted accurately. A model of oxide damage due to plasma etching is proposed.<>