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Type of Defect: |
Black Speck (2/3) |
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Description: |
Contamination of Inorganic substances |
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Observation Method: |
Visible by the human eye |
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Recommendation Upon Observation: |
Better visibility using a Magnifier under polarized light / visible as a bright speck |
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Other Evaluation Method: |
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Cause |
Countermeasure |
| Contamination of airborne dirt (sands, metals or metal oxide etc.) |
Keep cleanness of the material hopper |
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Contamination of airborne dirt (sands, metals or metal oxide etc.) |
Purge the cylinder |
| Contamination of airborne dirt (sands, metals or metal oxide etc.) |
Use proper material handling procedure |
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Contamination of metal particles from equipment |
Check and clean the equipment |
| Contamination of metal particles from equipment |
Purge the cylinder |
