PolyCHECK® Wipes & Swabs
Dry Particle Collection
Instructions for Use
1. Purpose & Scope
Collect particulate contamination from equipment surfaces for qualitative analysis and identification (e.g., SEM/EDX/FTIR). The method relies on dry electrostatic/triboelectric attraction of PolyCHECK® Swabs or Wipes to lift and retain loose particles.
2. Safety & Readiness
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PPE: Low-lint cleanroom gloves, mask, gown.
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Surface condition: Must be visibly dry (pause wet cleaning/rinsing beforehand).
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Sequencing: Always sample before cleaning. Work clean → less-clean and top → bottom.
3. Materials
PolyCHECK® Swabs
PolyCHECK® Wipes
Small Cleanroom Resealable Bags
Large Cleanroom Resealable Bags (Master Bag)
Labels & Alcohol-Resistant Marker
Camera/Phone
Optional: UV Flashlight
4. Sampling Principles (Core Rules)
- Dry on dry only — no pre-wet, no solvents or water.
- Light, low-angle strokes; avoid aggressive scrubbing that can generate wear debris.
5. Swab Procedure (Slits, Lips, Grooves, Tight Spots)
Don fresh gloves; Open a dry PolyCHECK® swab at point of use.
Hold at a low angle; make 5 parallel straight strokes across a defined area (~1–4 cm²), rotating to a clean face each pass.
Make 5 perpendicular strokes (cross-hatch) using unused faces.
Optional UV visualization: Illuminate the tip at a shallow angle with 365 nm UV to highlight captured particles; photograph for records.
Without touching the tip, place the entire swab head into a cleanroom resealable small bag; Expel excess air; seal. Record: tool/module, exact location, area (cm²), passes, swab lot #, take a photo of labeled bag.
Place all samples(individual small bags) into the large master bag; seal. Record: Company name, location, and label FM Assessment.
Best targets: VAT/slit valves, ESC peripheries, lift-pin holes, robot end-effectors, O-ring lands, fastener recesses or other equipment identification terminology.
6. Wipe Procedure (Slits, Lips, Grooves, Tight Spots)
Open a dry PolyCHECK® wiper and quarter-fold it once.
Using that single exposed quarter-fold face, wipe a defined 10 × 10 cm (or SOP-specified) area with S-strokes (~30% overlap). Do not switch faces during collection.
Optional UV visualization: With the sampled face exposed, use 365 nm UV at a shallow angle to highlight captured particles; photograph for records.
Refold once so the contaminated face is inside the fold to protect the sample during transport.
Place the folded wiper into a cleanroom resealable inner bag; Expel excess air; seal. Record: tool/module, exact location, area (cm²), passes, wipe lot #, take a photo of labeled bag.
Place all samples(individual small bags) into the large master bag; seal. Record: Company name, location, and label FM Assessment.
Best targets: chamber walls, transfer doors, viewport flanges, pump-deck panels, FOUP docks and other equipment identification terminology.
7. Packaging, Labeling & Transport
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Bags only: Use cleanroom resealable (inner + outer). Keep samples dry.
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Label the inner bag (not just the outer): Sample ID, date/time, collector, tool/module, exact location, area (cm²), media type & lot #, UV photo ID(s)
8. Documentation & Traceability
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Photograph each sample location and the sampled face (if UV was used).
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Maintain a simple site map (thumbnail sketch + photo IDs)
9. Do’s & Don’ts (Quick Reference)
Do
- Sample before cleaning.
- Keep surfaces & media dry at all times.
- Use consistent areas and pass patterns.
- Use UV (365 nm) to visualize particles and photograph before bagging.
- Label each inner bag.
- Place all samples.
Don’t
- Don’t pre-wet or add liquids (UPW/IPA/cleaners).
- Don’t touch collection faces with gloves/forceps.
- Don’t composite multiple sites in one bag unless the lab requests a composite.
9. Frequently Asked Questions (FAQ)
Q1) Why must sampling be dry-on-dry?
Dry media on dry surfaces maximizes electrostatic/triboelectric capture, avoids smearing/dissolving residues, and preserves morphology/chemistry for SEM/EDX/FTIR.
Q2) What if the surface is damp or tacky?
Wait until fully dry or choose a comparable dry region. If you must proceed, note the condition on the label/CoC and notify the lab—interpretation may be limited.
Q3) How large an area should I collect?
Swabs: 1–4 cm² targeted zones. Wipers: typically 50–200 cm². Always record area and pass pattern for apples-to-apples trending.
Q4) Can I change wiper faces mid-collection?
No. For sampling, use one quarter-folded face only. After optional UV/photo, refold once so the contaminated face is inside for transport.
Q5) How and when should I use UV?
Use a handheld 365 nm UV at a shallow angle to highlight captured particles on the sampled face or surface. Photograph for the report, then refold/bag.
Q6) Can PolyCHECK® provide counts per cm²?
No—PolyCHECK® is for qualitative identification and relative loading/trending. If you need counts, run a validated counting method in parallel.
Q7) Any ESD concerns?
Follow site ESD protocol. Don’t ionize the swab/wiper during collection (it reduces static pickup).
Schedule an appointment with our expert technicians and start closing CAPAs & Non-Conformance Reports(NCR)!
About Foamtec WCC
Foamtec's mission is to enable contamination control professionals to improve particle control in clean rooms by solving surface contamination challenges. The Wilshire Contamination Control Division of Foamtec International supplies clean room mops, foam swabs, microfiber swabs, foam wipers, microfiber wipers, UltraSOLV® ScrubPADS to address clean room cleaning and the critical cleaning of process equipment.