Defect Migration of Multi-chip Modules Using Structural Test

The high-volume production and rework of 100 chip MCMs in a structured test environment and the rationale for defect migration (continuous quality improvement) is described. Manufacturing and rework of these MCMs requires continuous improvements in chip quality. This necessitates in- expensive diagnostics at chip, INICM and system level so that the root cause of the defects can be determined and the chip fabrication, test, and burn-in processes improved. The requirements for and implementation of structural test (to detect both stuck fault and delay defects), diagnostic automation, system level test correlation, coordination of defect tracking at the system, MCM and chip level and defect model correlation are discussed. The MCMs are designed using level-sensitive scan design (LSSD). Through the use of structural test and it's associated diagnostics, the details of the defects are sup- plied to the chip fabricator who successfully improves the chip quality levels.