qualification

Qualification validates that equipment, processes, or materials meet specifications before production use. **Types**: **Equipment qualification**: New tool installed and tested before production. **Process qualification**: New recipe validated with test wafers and electrical results. **Material qualification**: New chemical, gas, or consumable validated for quality. **Stages**: IQ (Installation Qualification), OQ (Operational Qualification), PQ (Performance Qualification). **IQ**: Verify correct installation, utilities, documentation. **OQ**: Verify operation within specified parameters. **PQ**: Verify consistent production-worthy results. **Wafer runs**: Qualification typically requires multiple lots of wafers to demonstrate consistency. **Acceptance criteria**: Defined specifications for CD, uniformity, defects, electrical parameters. **Documentation**: Complete records of qualification testing and results. **Requalification**: Required after maintenance, changes, or extended downtime. **SPC**: After qualification, ongoing SPC monitoring maintains qualified state. **Duration**: Days to weeks depending on scope and acceptance criteria.