Subject: Re: discontinue 950K
From: James Conway <jwc@snf.stanford.edu>
Date: Wed, 15 Oct 2003 12:26:28 -0700
Wed, 15 Oct 2003 12:26:28 -0700
Hi everyone:

Just to clarify Mahnaz's last email...

 - Microchem Corp. materials are more consistent lot to lot :: batch to
batch.  In the future we will only order PMMA from Microchem and NOT Arche
or Gallade Chemical.

 - This work refers to the 2% 950,000 Molecular Weight PMMA material only
and has no reference to the STD. 5% 495,000 Molecular weight PMMA.  The 2%
950K MW PMMA  is our high resolution Ebeam resist used in single and
bi-layer processing in our lab here.

The 5% 495,000 Molecular weight PMMA is our Standard PMMA material system to
result in slightly thicker films to ~300 - 250 nm thickness and it is the
workhorse Ebeam resist we use here at SNF.

While the 9% 950,000 MW PMMA is inventoried here and is currently 'in the
house'.  I see little to no apparent need for us to stock it, as that most
users of this material are using it for planarization and surface protective
films, and we have no process defined to work with it.  We should carefully
review the need to determine if we wish to stock, provide process support,
and track results of this material with users.  I occasionally see users
confused with the various viscousities and molecular weights of these
materials resulting in application of the material types in error leading to
various process results.

THANK YOU,

James Conway


Mahnaz Mansourpour wrote:

> Hello all,
>
> It has been decided to discontinue the order of OCG PMMA 950k 2%.
> Apparently the batch to batch does not produce the same result and James
> gets better result from Pmma 495K mw  2%.
> We still have 3 small bottles of these materials and one whole big
> bottle in the box that Dave will try to see if we can send it back ( if
> not we will use it up, but please no more ordering of these from Gallade
> Chemical Inc.).
> Please any problem or issue with this let James or me know.
> Apparently that goes for pmma 9% as well, do we need it? the usage is
> very low?
>
> mahnaz


Hi everyone:

Just to clarify Mahnaz's last email...

 - Microchem Corp. materials are more consistent lot to lot :: batch to batch.  In the future we will only order PMMA from Microchem and NOT Arche or Gallade Chemical.

 - This work refers to the 2% 950,000 Molecular Weight PMMA material only and has no reference to the STD. 5% 495,000 Molecular weight PMMA.  The 2% 950K MW PMMA  is our high resolution Ebeam resist used in single and bi-layer processing in our lab here.

The 5% 495,000 Molecular weight PMMA is our Standard PMMA material system to result in slightly thicker films to ~300 - 250 nm thickness and it is the workhorse Ebeam resist we use here at SNF.

While the 9% 950,000 MW PMMA is inventoried here and is currently 'in the house'.  I see little to no apparent need for us to stock it, as that most users of this material are using it for planarization and surface protective films, and we have no process defined to work with it.  We should carefully review the need to determine if we wish to stock, provide process support, and track results of this material with users.  I occasionally see users confused with the various viscousities and molecular weights of these  materials resulting in application of the material types in error leading to various process results.

THANK YOU,

James Conway
 

Mahnaz Mansourpour wrote:

Hello all,

It has been decided to discontinue the order of OCG PMMA 950k 2%.
Apparently the batch to batch does not produce the same result and James
gets better result from Pmma 495K mw  2%.
We still have 3 small bottles of these materials and one whole big
bottle in the box that Dave will try to see if we can send it back ( if
not we will use it up, but please no more ordering of these from Gallade
Chemical Inc.).
Please any problem or issue with this let James or me know.
Apparently that goes for pmma 9% as well, do we need it? the usage is
very low?

mahnaz