MIL-PRF-38535K
6.5 Discussion. The foundation of generic qualification is the requirement for a Quality Management (QM) program within
the manufacturing environment. QM requires that all levels of management and non-management be actively involved in the
commitment to quality. Also, a TRB is to be established to control, stabilize, monitor and improve the qualified technology.
The TRB will develop a QM plan that outlines how the manufacturing operation for a given technology is controlled, monitored
and improved throughout its entire "life cycle". Key aspects of this plan are the establishment of statistical process control
(SPC), field failure return programs, corrective action procedures, quality improvement, and any other approaches required to
control and improve product quality and reliability. These requirements are detailed in this specification. Further, this
specification describes procedures and requirements for manufacturer's listing on the QML for integrated circuits.
Manufacturers listed on the QML will be able to produce microcircuits without the need for extensive end-of-manufacturing
qualification testing and QCIs on each device design. The reduction of the end-of-manufacturing testing will be replaced with
in-line monitoring and testing and SPC. Also, surrogate devices, such as the SEC will be used to assess the technology's
reliability. Introduction of this methodology shifts the emphasis from the need of individual microcircuit qualification to process
(technology) certification and qualification. This will accelerate the microcircuit insertion cycle of high quality and reliable
microcircuits.
The generic qualification philosophy, leading to QML, is a process by which a manufacturer acquires a manufacturing line or
technology flow certification and qualification. Ongoing monitoring techniques will be used to maintain QML status. The
manufacturing line consists of facilities and procedures appropriate to accomplish the design, mask making, wafer fabrication,
assembly, package and testing of microcircuits (see figure 1). Figure 2 illustrates six possible combinations of a
manufacturing line utilizing three design centers, two mask fabrication facilities, three wafer fabrication facilities, two package
and assembly sites and two test facilities. The procedure of generic qualification is accomplished in two stages; certification
and qualification. The process of certification is the recognition of evidence by the QA that the manufacturing line is capable of
producing microcircuits of high quality and compliant with the requirements of this specification. Qualification is the actual
demonstration of the certified manufacturing line capabilities by producing "first pass" microcircuits compliant with the
requirements of this specification and the device specification. On figure 2, each block can be individually reviewed, but is to
be certified as a flow. The only process flow which would be qualified (QML listed) would be the group of blocks which are
linked together and tested during qualification. The letters "A" and "B" indicate a QML flow where qualification testing has
qualified a complete path. The other paths are not QML until certification and qualifications testing of those processes are
done.
39