Re-evaluating dynamic stack vs. HGA testing

摘要

To meet HGA testing requirements, the hard disk drive (HDD) industry has traditionally relied on dynamic testing of a very high percentage of HGA assemblies, usually followed by either a quasi-static test and/or a dynamic test of the stacks. Although to date this has resulted in acceptable yields and rework costs, today's aerial-density curves and drive-capacity demands indicate a move to both fewer heads and disks. Simultaneously, the HGA is increasing in ESD sensitivity and in complexity with individual unique interconnects like flex on suspension (FOS) or Hutchinson Technologies thermosonic bonded suspension assemblies (TSA) interfaces, chip on suspension, and the advent of micro-actuators. This, coupled with automation requirements, suggests that the current test paradigm should be re-evaluated.