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Hello Labnetworkers,</div>
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Has anyone tried one of the TMAH substitutes that have become available?</div>
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How do they work? Are your users satisfied with their results?</div>
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For background, TMAH (tetramethylammonium hydroxide) is widely used in commercial resist developers (3%) and for HSQ developing (25%). In its 25% concentration, TMAH is a potent contact neurotoxin, which is fatal roughly 75% of the time, for exposures greater
than 7.5% of body area. Nasty stuff.<br>
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Several companies now have safer alternatives available, which we'd like to try out, such as:</div>
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<font class="ContentPasted0" face="Times New Roman,Times,serif">Envure 3330</font> (Sachem Chemical),
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E-Grade THEMAH SLM ((hydroxyethyl) methylammonium hydroxide, from Huntsman Chemical), and</div>
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Novo-safe SE-33 (ethyl tri-methy ammonium hydroxide from Transene).</div>
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We are particularly interested in using one of these as an HSQ developer, so we can do away with 25% TMAH.<br>
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Any experiences, good or bad, will be most welcome. <br>
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Thanks,</div>
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Mac Hathaway</div>
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Senior Process and Systems Engineer</div>
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Harvard Center for Nanoscale Systems<br>
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