Specific Process Knowledge/Wafer cleaning/7-up & Piranha: Difference between revisions
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Cleaning of wafers or masks with sulphuric acid can be done either in a dedicated tank "7-up" or in the fume hood in a beaker "Piranha" | Cleaning of wafers or masks with sulphuric acid can be done either in a dedicated tank "7-up" or in the fume hood in a beaker "Piranha" | ||
Both 7-up and Piranha removes heavy organics. | Both 7-up and Piranha removes heavy organics. | ||
Always use one of these after KOH etch or hot phosphoric acid etch to remove alkali ions before further processing. 7-up and Piranha are also used as cleaning solutions after stripping resist. | Always use one of these after KOH etch or hot phosphoric acid etch to remove alkali ions before further processing. 7-up and Piranha are also used as cleaning solutions '''after''' stripping resist. | ||
[[Image:7-up_6inch.jpg|300x300px|right|thumb|7-up 6" in cleanroom D3. <br\> -Up to 25 wafers of 4" or 6" at a time.<br\> -Materials allowed: Silicon, Silicon oxide, Silicon nitride, PolySi]] | [[Image:7-up_6inch.jpg|300x300px|right|thumb|7-up 6" in cleanroom D3. <br\> -Up to 25 wafers of 4" or 6" at a time.<br\> -Materials allowed: Silicon, Silicon oxide, Silicon nitride, PolySi]] | ||