Hi

For the rough edge, I suspect you didn't do lift off
well. Generally there are two ways for producing
overhang profile, which can make the wanted and
unwanted metal discontinous. One way is Chlorobenze
modifying process. Photoresist is soaked in
chlorobenze before or after exposure, a photoresist
undercut can be produced after development process due
to the different resist etch rate between the
chlorobenze modified surfacial layer and the bottom
layer. The other way is using a LOL based bilayer
resist. Photoresist is spun on a LOL2000 risist layer,
which is not sensitive to UV source. By changing the
development time, desirable overhang can be gotten
because the LOL2000 can be etched without expoure and
faster than photoresist. Note too big overhang will
drop off.

I have succeeded in lifting off even 400nm metal
clearly. If detailed information is needed. such as
process parameter, pls contact me.

--- Jeff Kettle дµÀ:

> Hi all,
>
> Has anyone ever tried fabricating Au patterns on
> mica?
>
> We have patterned using a mask aligner 2 electrodes
> with a gap in between each electrode of 5um only to
> find the thermal evaporation of 5nm Cr/40nm Au after
> lift-off doesn't adhere well, leaving very rough
> edges where the edges should be straight. The
> photolithography stage goes well. If anyone has any
> ideas or experience working with au/mica, we'll be
> grateful.
>