MIL-PRF-38535K
FIGURE 1. The QML manufacturing line.
FIGURE 2. Combinations of a manufacturing line.
QM does not stop with a manufacturer listed on the QML. This specification identifies the necessary screens which QML
devices are to be capable of meeting. These screens can be reduced or changed by the manufacturers' TRB when gathered
reliability data on the technology indicates that such changes are substantiated. The philosophy of generic qualification
incorporates the idea that high quality and reliable microcircuits can be obtained without excessive testing if the processes are
properly monitored and controlled at each step of the manufacturing line. The following describes the monitors and controls
that may be used.
a. The design procedure and tools are controlled in such a manner that the ensuing microcircuit design performs only
with limits that have been shown to be reliable for the technology being used, within the constraints of established
design rules (electrical, geometric and reliability).
b. The mask fabrication facility is controlled such that an error free mask is produced from the microcircuit design
database. Monitoring, controlling and reducing defect density is helpful in obtaining error free masks.
c. The wafer fabrication process is controlled with the following: Use of in-line statistical control; a parametric monitor
structure for measuring electrical parameters; a TCV structure to study intrinsic reliability mechanisms; and a SEC to
monitor the fabrication process and to serve as a surrogate microcircuit for reliability testing.
d. The package and assembly facility is controlled with emphasis on in-line statistical process control of all assembly
steps.
e. The test area controls consist of test equipment accuracy and calibration as well as a controlled interface to the
microcircuit design center.
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ACTEL [ Actel Corporation ]
