Hey,

Let me describe the process conditions and I hope that will discuss the
problems in more detail.

The substrate is Silicon nitride deposited on Si by LPCVD.

Spin coating: AZP 4620 for 2000rpm for 30 secs The  thickness of the resist
came out to be 12um.

Pre baking for 5 mins at 120'c in convection oven

Exposure: 400mJ/cm2

Development time: 80 secs in AZ400k:Di water= 1:4

The patterns in the mask ranges from 10 microns upto 100 microns maximum.

When I  developed according to the above conditions, I saw that the patterns
did not follow the mask patterns at all.Most of the square patterns came out
closely to circle as well ovals mostly.Also some of the areas were very
poorly developed.

The thick PR mold will be used for electroplating of Copper.
Also in the other substrate(GLASS)  the PR  will be used for lift off after
a thick metal deposition (evaporation) of around 5 um.

Any suggestions will be highly appreciated.

Best wishes

Anirban


On Fri, Jul 17, 2009 at 1:05 PM, Brad Cantos  wrote:

> Anirban:
>
> You will need to describe your problem a bit more specifically.  When you
> say "patterns were ridiculous" do you mean they were larger than you
> expected?  Was the pattern not true to the mask?  Also please indicate the
> parameters that you used, specifically the exposure tool, exposure dose,
> thickness of resist, developer, etc., so that any advice may be helpful to
> you.  You also mention you want to " perform lift off" and then go on to say
> electroplating.  These are different processes entirely.  Please describe
> what you are trying to accomplish.
>
> Brad Cantos
> brad.cantos@holage.com
> http://holage.com

ANIRBAN
Electrical Engineering
Louisiana State University
Baton Rouge
70802,USA