Subject: Re: Ma-N 2403 negative Ebeam resist and YES oven
From: James Conway <jwc@snf.stanford.edu>
Date: Wed, 26 Nov 2008 09:56:53 -0800
Wed, 26 Nov 2008 09:56:53 -0800
Hello All:

I though we had beat this thread to death before.

I think it all depends on the cleanup used prior to the MaN-spin 
coating.  You cannot reply on a previous prime layer to stay intact 
after other resist processing. It is just a delicate mono-layer!!!
This week I coated several wafers with 1.0 um oxide after YES priming 
and MaN-2403 adhesion was fine with no blistering evident.
These wafers had been cleaned on wbnonmetal using the 9:1 H2SO4:H2O2 
etchant, 6X Dump rinses and 1X SRD rinsed and then immediately put into 
the prime oven.  The wafer was coated with resist immediately after the 
prime process was completed.

You shouldn't be surprised in the least that you had adhesion issues on 
your wafer after you stripped off ZEP- 520 resist and had employed a 
previous YES primed layer -- it likely became contaminated in the two 
days it sat out.  YES prime layers should be consider good for about a 
maximum of 24 hours before you should consider repeating the YES Prime 
after a complete wafer clean sequence is repeated.

If you obtain excellent adhesion which passes NIST Peel test I and II 
without YES prime fine just do it in your process. 
You will need to provide more data and higher N counts before I will buy 
in that priming is not necessary for my process which was tested over 
more than 20 wafer lots to date.

All the Best for the Holiday,

James Conway




Arash Hazeghi wrote:
> Greetings,
> A while back I posted about an issue not being able to spin Ma-N 2403 negative ebeam
resist on wafers primed in the YES oven. Since then, I have only been using the standard
150C singe oven prior to Ma-N spin and the results have been good. Today I tried spinning
MaN on a wafer that had gone in the YES oven (the wafer had ZEP on it before and thus
primed in YES two days ago) and again to my surprise adhesion was very poor.
> Although HMDS prime is recommended in the official data sheet for Ma-N2403, I have
come to the conclusion that currently it is not compatible with the recipe used in the
YES oven, so I thought I'd share this with other users who may want to use this resist.
This also confirms Jim Kruger's findings. 
>
>
> Best,
> Arash
>   


Hello All:

I though we had beat this thread to death before.

I think it all depends on the cleanup used prior to the MaN-spin coating.  You cannot reply on a previous prime layer to stay intact after other resist processing. It is just a delicate mono-layer!!!
This week I coated several wafers with 1.0 um oxide after YES priming and MaN-2403 adhesion was fine with no blistering evident.
These wafers had been cleaned on wbnonmetal using the 9:1 H2SO4:H2O2 etchant, 6X Dump rinses and 1X SRD rinsed and then immediately put into the prime oven.  The wafer was coated with resist immediately after the prime process was completed.

You shouldn't be surprised in the least that you had adhesion issues on your wafer after you stripped off ZEP- 520 resist and had employed a previous YES primed layer -- it likely became contaminated in the two days it sat out.  YES prime layers should be consider good for about a maximum of 24 hours before you should consider repeating the YES Prime after a complete wafer clean sequence is repeated.

If you obtain excellent adhesion which passes NIST Peel test I and II without YES prime fine just do it in your process. 
You will need to provide more data and higher N counts before I will buy in that priming is not necessary for my process which was tested over more than 20 wafer lots to date.

All the Best for the Holiday,

James Conway




Arash Hazeghi wrote:
Greetings,
A while back I posted about an issue not being able to spin Ma-N 2403 negative ebeam resist on wafers primed in the YES oven. Since then, I have only been using the standard 150C singe oven prior to Ma-N spin and the results have been good. Today I tried spinning MaN on a wafer that had gone in the YES oven (the wafer had ZEP on it before and thus primed in YES two days ago) and again to my surprise adhesion was very poor.
Although HMDS prime is recommended in the official data sheet for Ma-N2403, I have come to the conclusion that currently it is not compatible with the recipe used in the YES oven, so I thought I'd share this with other users who may want to use this resist. This also confirms Jim Kruger's findings. 


Best,
Arash