Discussion Group Summary Reliability Test Structures

The Reliability Test Structure Discussion Group covered a range of topics. The first issue was the use of test structures. In general it was agreed that test structures were used both for production monitoring and for qualification testing. The test structures used for production monitoring were generally smaller and fit into scribe lanes or a few drop in die. Larger areas were generally available for structures intended for qualification testing. New process qualification, process change qualification and new equipment qualification testing can often be tested using special “qualification wafers” with large areas covered with test structures. These use test structure die that occupy large parts of a reticule, generally areas in multiples of a die area. These structures can be used to address “defect density” issues which contribute to infant mortality problems as well as wearout failure mechanisms.