Hi,

Use AZ1400 or 1350 as mask, RIE with CF4. You can design the lens with the
depth between 0-2Pi, and it's easier for dry etching. 3 mask-aligning can
make more than 90 diffraction efficiency.  I think the group of Lincohn Lab
of MIT and some companies such MEMS OPTICAL INC should have this kind of
techniques.

Good Luck,

Hongjun Zeng, Ph.D.
Microfabrication Applications Laboratory (MAL)
University of Illinois at Chicago
ERF Building, 842 W. Taylor Street
Chicago, IL 60607-7022
Room 3014 ERF
Tel.: 312-413-5889, Fax: 312-996-6465

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Message: 5
From: Ali Razavi 
To: "'mems-talk@memsnet.org'" 
Date: Wed, 1 May 2002 12:27:34 -0400
Subject: [mems-talk] Question: Microlens Fabrication
Reply-To: mems-talk@memsnet.org

Hi,

  We plan to fabricate microlens arrays on quartz (fused silica).
The diameter of each microlens is in the range of 50-200um and
the f-# varies in the range of 2-10.
  We are considering to fabricate them using photoresist reflow
followed by RIE. Therefore, I am very interested to find any
reference that describes the fabrication process, including the
type of resist, detailed process for both reflow and RIE. Do you
have any recommendation?

  Thanks,
 -Ali :)
-------------------------
 Ali Razavi, Ph.D.
 Room 455, Manufacturing Research Center
 Gerogia Institute of Technology, Atlanta, GA 30332-0405
 Phone: 678-637-1634, Fax: 404-894-9342
 E-mail: arazavi@pmrc.marc.gatech.edu