Unity request for p5000etch

[Ed Myers]

All,

Element by element:

Pr ( Praseodymium): Fluoride volatility similar to Y, Sm, Nb, Ce and La 
near -130 kcal/gram-atom.  Not easy to form.
Co: No volatile compound will be formed, hence it will reside in the chamber
Mn: Has similar fluoride volatility as Co and Ni,. Has a similar vapor 
pressure as indium (right on the edge of acceptable)
La: Fluoride volatility similar to Y, Sm, Nb, Ce and La near -130 
kcal/gram-atom.  Not easy to form.
Sr: Below the indium vapor pressure cut-off.  Free energy of formation 
-140 kcal/gram-atom for both Sr and Ca
Ca: Below the indium vapor pressure cut-off.  Free energy of formation 
-140 kcal/gram-atom for both Sr and Ca

Lidia's comment " We may have likely have to use a larger component of 
sputter etch ie Ar in the etch." is very telling.  We will  be approving 
the P5000 to be used as a ion sputter etch tool.  With other options 
available to them, my vote is no.

Ed


On 11/3/2011 10:09 AM, Lidia Vereen wrote:
> Mary,
>
> There are two materials. They are conductive metal oxides.  Their
> composition is highly confidential.
>
> The materials have Pr, Co, Mn, La, Sr, Ca.   If Mn is a problem,  we do not
> necessarily have to use that composition.
>
> We would prefer to use a chemical etch ie CF4, CHF3, etc.  I doubt the
> chlorine based chemistries would work.  We may have likely have to use a
> larger component of sputter etch ie Ar in the etch.
>
> Given the options open to us, access to the P5000 is very important.
> Please let us know your decision as soon as is feasible.
>
> Thanks
>
> Lidia
>
> -----Original Message-----
> From: Mary Tang [mailto:mtang at stanford.edu]
> Sent: Thursday, November 03, 2011 9:41 AM
> To: lvereen at unitysemi.com
> Cc: specmat at snf.stanford.edu; jbumgarner at snf.stanford.edu; maurice stevens
> Subject: Unity request for p5000etch
>
> Hi Lidia --
>
> We've been reviewing your request for etching CMO materials on P5000
> based on the info you'd sent last August.  The sticking point has been
> the Manganese -- but when I spoke with Mary Calarrudo, she said that the
> material to be etched was not Cobalt manganese oxide (which I think we'd
> assumed "CMO" meant).  She says CMO is Complex Metal Oxide.
>
> So, apologies for the delay, but I'm confused.  Could we get a
> definitive description of the elements in the films you would like
> etched in the p5000?  As well as some description of the type of process
> (chemistry and chamber) you'd like to use?  You do not have to disclose
> anything proprietary but part of the agreement of working at SNF is
> sharing info about composition and processes to the degree other
> researchers' work may be affected.  So, specific composition is not
> needed, but certainly the elemental components would be helpful,
> especially if things appear at trace levels.
>
> Thanks,
>
> Mary
>
>
>