Hi Erkin,

Using h-line (405nm) dominated UV broadband and
glycerin gap compensation, you can get reasonable good
SU-8 structure, with 1150um high and 6um feature size.
Microstructures with height up to 2 mm and good
sidewall quality also can be obtained.

The sidewall quality can be controlled by the
optimization of i-line/h-line ratio.

Reference:
"A numerical and experimental study on gap
compensation and wavelength selection in
UV-lithography of ultra-high aspect ratio SU-8
microstructures " SENSORS AND ACTUATORS B-CHEMICAL 110
(2): 279-288 OCT 14 2005

"UV-LIGA fabrication of microscale two-level mold
inserts for MEMS applications" SPIE, v 5717,2005, p
175-184

Good luck

Regards

Ren Yang

--- erkin seker  wrote:

> Hi,
>
> I want to build vertical SU8 beams on a silicon or
> quartz substrate, and I
> would like to have an idea about the maximum aspect
> ratio I can get with
> thick (>100um) SU8 resist to yield near vertical
> sidewalls and intact
> structures.  Could anybody please forward his/her
> idea on this?