Hi
You can use photoresist for masking, AZ or Shipley. 3um photoresist can
do 80um Si and upto 100um as well. It works perfect on Alcatel DRIE.

kind regards

===================================
Salam R. Gabran, MASc.
Research associate, PhD. Candidate
Center for Integrated RF Engineering
(CIRFE Lab)
ECE Dept., University of Waterloo,
200 University Avenue West
Waterloo, Ontario, N2L3G1
cell.: 519-729-8066
Web: www.ece.uwaterloo.ca/~sgabran


On 2:59 PM, yasser sabry wrote:
> Dear All,
>
> I am trying to etch Si with Al as DRIE mask and using LF substrate bias
pulses.
>
> I got Si grass everywhere and was explained to be due to micromasking of Al
> (sputtering and redeposition)
>
> The problem disappears if RF continuous substrate bias is used.
>
> But I need to use the LF to overcome notching effect.
>
> Has anyone succeeded before an etch with Al and LF without having Si grass?
Any
> process suggestions will be appreciated.
>
>
> Thanks in advance,
> Yasser Sabry
>
> Doctorante ESIEE
> Cité Descartes,
> 2 Bd Blaise Pascal,
> F-93162 Noisy-le-Grand Cedex, FRANCE
> +33604488624
>