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| 1.Cleaness ball surface (No dendrite) |
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| 2.No hole on ball surface |
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| 3.Magnify ball surface without hole |
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| 4.Magnify cross section |
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| 5.Magnify cross section(No hole,Dendrite) |
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| Metal formation is not changed after cleaning & coating |
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Luster by cleaning & coating of oxidation layer on ball sucface
good wettability and spreadiability
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Improved solderability with weak flux
Prevent missing ball and trouble for no hole and oxidation layer
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| 1.Rough ball surface(Dendrite) |
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| 2.Many hole on ball surface |
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| 3.Magnify ball surface with hole |
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| 4.Magnify cross section |
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| 5.Magnify hole area on cross section |
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| Problem |
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Extended ball surface area by rough surface
bad wettability and spreadability by increasing oxidation |
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Detected S, Cl, Si on surface |
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