MIL-PRF-38535K
APPENDIX H
c. Process qualification.
(1) Test vehicle.
(2) Single or 1 lot.
(3) Environmental conditions (for fabrication, test, assembly, and storage).
(4) Accept/reject criteria.
(5) Perceptivity of tests (TCV and test programs shall be capable of highlighting the critical parameters and
discerning the results that identify accept/reject criteria).
(6) Process baselined for qualification ( no further changes required after characterization).
(7) Qualification by test, similarity, or space heritage (Process or device that has been produced and passed space
level testing and has flown in a space environment similar to the environment expected for this process/device).
d. Fabrication.
(1) TRB program (or equivalent) (see G.3.2.2).
(2) SPC and in-process monitoring program (see H.3.2.1.3).
e. Radiation hardness assurance (RHA) (see appendix C), if applicable.
H.3.2.1.3 SPC and in-process monitoring program. An in-process monitoring system should be used by the manufacturer
to control key processing steps to insure device yield, reliability, and RHA if applicable. The monitoring system can utilize
various test structures, methods, and measurement techniques. The critical operations to be monitored should be determined
by the manufacturer based on their experience and knowledge of their processes. The resulting data should be analyzed by
appropriate SPC methods (in accordance with the requirements of TechAmerica EIA557 to determine control effectiveness.
The following should be addressed for the wafer fabrication process, as a minimum, by the manufacturer:
a. Incoming mask and fabrication process materials.
b. Equipment used for wafer fabrication.
c. Doping material concentration.
d. Cross section diffusion or concentration profile, and epitaxial (EPI) layer.
e. Passivation or glassivation.
f. Metallization deposition.
g. Resultant line width.
h. Passivation process temperature and time.
i. Diffusion, implant anneal process temperature, and time, or both.
j. Sintering or annealing temperature and time.
k. All reliability test data including the standard evaluation circuit (SEC).
l. Mask inspection and defect density data.
m. Parametric monitor test data.
n. Photoresistive processing (including rework procedures).
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ACTEL [ Actel Corporation ]
