Hi Andrea,

The sidewall angle depends on many process parameters. What is the thickness
of your resist?

Earlier I experienced a similar problem which I overcame by increasing the
resist thickness and reducing the baking temperature. This in turn minimises
the resist reflow which causes angular side walls. Again it depends on the
geometry of the pattern as well. Perhaps you may try for your pattern as
well to see if this improves.

Regards,
Prasanna

On Sun, Jan 17, 2010 at 1:20 PM, Andrea Mazzolari wrote:

> Hi All,
>
> i need to pattern S1813 with vertical sidewalls, but at the present time i
> get an angle of about 54 deg. Awful...
> My maskaligner is an old karl suss.
>
> Here is my procedure:
> -spinning of S1813
> -soft bake 3 min at 115 deg
> -photolitography in contact mode (150mJ)
> -development in MF319 (about 45 seconds)
> -hard bake 15 min at 115.
>
> Any suggestion to improve the sidewall angle ?
>
> Best regards,
> Andrea
>