Hello All-

Thanks for all your responses. They have been useful.

Yingnan-

I am using AlN substrate with sputtered copper prior to the DF process. I
have tried using oxygen plasma in the past, post development. It seems to
oxidize the copper. Also, on visual inspection the foot of the DFR seemed
unaffected.

Ningyuan-

We agree, the problem could be from insufficient rinsing post development.
We have to address it by rinsing for at least one minute in DI water and
then immerse it in water for about a minute before spray rinsing and drying.
There is not much visible at the foot of the DFR post development. However,
post flood exposure there is a shadow like appearance at the foot of the
resist. We believe could also be causing a problem. I am interested in
trying the two step develop and would share the results.

Ying-Tao-

Thanks Ying-Tao. The issues you mention could cause a problem.

Denis-

I am using a 3 mil dry film from Eternal, E9230. The feature size is huge.
These are about 8 to 10 mils.

Thanks again. Please feel free to to ask if there are any questions or
suggestions.

Regards,

Sandeep




On Mon, Aug 9, 2010 at 12:13 PM, Sandeep Makhar  wrote:

> Hello All-
>
> We are pattern plating copper using a negative dry film photoresist. Post
> plating we observe that there is some non-plated area between the dry film
> and the plated area. It seems that this area is not wetted during the
> plating operation. Does anyone know why this would happen? Thanking you.
>
> Regards,
> Sandeep
>