can you elaborate on the bump mask? I am curious. a quick google did not reveal any thing.
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<br />I am simply experimenting of a cheap way to solder these LGA chips
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<br />I forgot to cc the lab
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<br /> (igoogle does not have a reply all)
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<br />On , Michael Ayukawa <mike.ayukawa@gmail.com> wrote:
<br /> That is good stuff. Were you planning on using it as an etch mask?
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<br /> Or are you thinking something completely different? People usually use Kapton if they
<br /> plan to retain it as a dielectric layer in the stack. So perhaps you are using this for
<br /> what would be called a "bump mask"?
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<br /> You really don't need the high temp properties for wet chemical processes.
<br /> The interface to the Cu is probably more important (etchant can quickly move along the
<br /> interface). We used to use special adhesion promoters and bakes to avoid
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<br /> jeanmarc.leblanc@gmail.com wrote:
<br /> I was going to buy this
<br /> http://www.ebay.ca/itm/Kapton-Polyimide-100TAB-E-8-x12-3-Sheets-Free-S-H-/370109637919?pt=LH_DefaultDomain_0&hash=item562c40e51f
<br /> From what I read, that is the metrial that is recommended for this kind of thing and cuts well with lasers