Nikky
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Al2O3
What chemical need to use to remove Al2O3 after deposition?
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kclo4
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Sodium hydroxide should work.
Al2O3 + 3 H2O + 2 NaOH → 2NaAl(OH)4
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chemoleo
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Thread Moved
24-3-2009 at 19:15 |
woelen
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It depends on how the Al2O3 is deposited. If this is from a high-temperature reaction, then certainly the dissolved NaOH-method does not work. Al2O3
becomes extremely inert when it is calcined and one needs molten NaOH to get it dissolved.
if the Al2O3 is formed from aqueous solution and is not calcined, then things are different. Such non-calcined Al2O3 (better: Al2O3.nH2O) easily
dissolves in an aqueous solution of NaOH.
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PHILOU Zrealone
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Also depends on what it is deposited!
Maybe what is proposed to remove the Al2O3 is not suitable for the support...
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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chief
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Al2O3 has a optimum of solubility around PH 9 ; but still only very slightly soluble. A very fine powder might dissolve over long timeframes ...
There is a reason for Al2O3 beeing a gemstone in the appearance of ruby and saphir: Over ages and ages it didn't dissolve and still can be found in
the nature ... : That's inertness !
[Edited on 26-3-2009 by chief]
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kclo4
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Nikky, can you give us more information on this problem of yours?
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daragh8008
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Quote: Originally posted by woelen  | It depends on how the Al2O3 is deposited. If this is from a high-temperature reaction, then certainly the dissolved NaOH-method does not work. Al2O3
becomes extremely inert when it is calcined and one needs molten NaOH to get it dissolved.
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any idea of what kind of etch rates you would get with that?? I have a 250 um wafer that need thinning.
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