A Minor Change in Sample Preparation Leads to Unexpected Qualification Fails During High Temperature Storage Stress Test

In today’s supply chains based on complex division of labor qualification plans must be executed at various levels of semifinished products. This study shows how a supporting process, assumed to be uncritical in terms of the qualification scope for a bare silicon die, is responsible for qualification fails. Although such failures are not relevant for the quality of the final product careful and thorough analysis is required to invalidate such failure modes.