Some of my colleagues ask outputcity to print transparency masks with
feature size down to 10 um. It takes about 24 hours for processing
including UPS shipping. For bigger patterns, a local shop is availabe.
But as Rupesh pointed out, the "transparency" mask from outputcity is
film mask which is thicker than that from the local shop. I guess the
local shop uses normal transparencies. If you are not limited by time,
I recommend film mask since it is more reliable and not much more
expensive than transparency. My experience with transparecy mask is
frustrating. Even for patterns bigger than 50 um, different batches of
printed transparency (with the same pattern) give different result
while keeping all the other aspects of fabrication process the same. I
don't know if anyone else on this list shares the same feeling. Hope
this helps.

Best,
Liu Yu

> Rupesh Sawant  wrote:
>  I wanted to pattern microfluidic channels on a glass substrates. For
> that i require to know the mask used. i am just giving a thought over
> the trasnparency mask. for that i need to know the minimum resolution
> of the printer which is used and the necessary details related to
> transparency mask. so if anyone in this group is having an experience
> with transparency mask then pls give me detail information about it.