Many prime contractors perform 100% tinning of vendor-supplied components to ensure good solderability during assembly. This practice encourages vendors to continue supplying components without regard for solderability re- quirements.
Subcontractor quality control is a key issue to the electronics industry. Most major companies have established supplier quality control programs that address this issue. In addition to performing 100% acceptance tests on all incoming material and parts, quality and certification programs are being enforced at the supplier level. Solderability testing, component storage, termination finish, and process control are being consolidated along with other technical requirements in a separate document in lieu of having them scattered throughout the purchase order. Management and technical teams are visiting suppliers to inform them of the use of their components, the end item it supports, problems that failures can cause, and why specification requirements are important. When applied, these practices have resulted in defect reduction, on-time delivery, elimination of repeat problems, and in many cases continuous process improvement.
Establish good incoming inspection and subcontractor control practices. These practices should include:
(1) Standardizing supplier requirements.
(2) Opening channels of communication.
(3) Monitoring supplier quality and yield data.
(4) Performing critical incoming inspection based on supplier's and prime contractor's histories.
(5) Developing and utilizing a supplier rating system.
(6) Providing feedback to the supplier.
(7) Returning discrepant components.
6.4 Future Investigations
Recommended areas for investigation include:
(1) New and innovative programs for subcontractor control.
(2) Effective rating systems that measure, analyze, and report supplier performance.