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Handling and Contamination Control for Critical Space Applications 297

TABLE 13.2
Mission Specific Environments and Contamination Sources

Mission Phase Molecular Particulate
Design Configuration, operation conditions, Configuration, operation conditions,
material selection material selection
Fabrication Materials outgassing, machining oils, Shedding, flaking metal chips, filings,
fingerprints, air fallout particle fallout, personnel
Assembly AMC, outgassing, personnel, Particle fallout, personnel, soldering,
cleaning, solvents, soldering, drilling, bagging material, shedding,
lubricants, bagging material flaking
Integration and test AMC, outgassing, personnel, test Particle fallout, personnel, test facilities,
facilities, purges purges, shedding, flaking,
redistribution
Storage Bagging material, outgassing, Bagging material, purges, containers,
purges, containers shedding, flaking
Transport Bagging material, outgassing, Bagging material, purges, containers,
purges, containers vibration, shedding, flaking
Launch Site Site bagging material, AMC, Bagging material, particle fallout,
outgassing, personnel, purges personnel, shedding, flaking,
bagging material, air fallout checkout activities, other payload
activities
Launch Ascent outgassing, venting, engines, Vibration and redistribution, venting,
companion payloads separation shedding, flaking
maneuvers
On-orbit Outgassing, UV interactions, atomic Micrometeoroid and debris
oxygen, propulsion systems impingement, material erosion,
redistribution, shedding, flaking,
operational events

(quantity and location), manufacturing processes, integration and test, packing and
packaging, transportation, launch, on-orbit operations, and return to Earth, if ap-
plicable. In addition, the assessment should identify the types of substances that
may contaminate and cause unacceptable degradation. The assessment results serve
as a general guideline to how extensive a CCP should be instituted.
Actual contamination control implementation of MEMS devices can be divided
into three major levels: design, packaging, and postpackaging. In the design level,
contamination control is focused in MEMS device configuration, operation condi-
tions, and material selection with an aim to minimize the contamination generation
potential. At the MEMS packaging level, adequate fabrication, assembly environ-
ments and processes are key to prevent contaminants from reaching MEMS devices.
The postpackaging level includes the integration and test of MEMS devices with
spacecraft and transport until their final operations on-orbit. At this final stage,
contamination control is essential in reducing accumulation of contaminants and
mitigating contamination impact on MEMS devices.

© 2006 by Taylor & Francis Group, LLC