[mems-talk] Photolithography - Resist peeling

[Bruce Neufeld]

Another possible solution of resisit adhesion is a H2 terminated clean used by ASM's epi and ALD group.  We've shown the ability to process SiGe epi at 650C without any bake step and SIC depostion for ALD.  The stability of the Si-H2 bonds last for 3-5 days.  I would like to try this for an lithography application.  If this is something you would like to try I can clean some samples in Phoenix.

Bruce Neufeld
Cereus Technology
480-664-7096
-----Original Message-----
From: "rmartin at systron.com" <rmartin at systron.com>
Sent: 8/15/2008 12:08 PM
To: "madhavrrao at yahoo.co.in" <madhavrrao at yahoo.co.in>; "General MEMS discussion" <mems-talk at memsnet.org>
Subject: Re: [mems-talk] Photolithography - Resist peeling

      Moisture and contaminations are the leading causes for resist
lifting.  You may want to ensure a clean, dry substrate before applying
photoresist (pre-clean and bake).  Then you may also want to use an
adhesion promoter (HMDS).  Good luck.
                                                     
       Ron Martin | Systron Donner Automotive        
  Job Title: Photolithography Engineer | Location:   
      Concord, CA | Extension: 6563 | Outside:       
                   1-925-671-6563                    
             E-mail: rmartin at systron.com 
                                                                           
---- Original message -----
From: madhav rao  <madhavrrao at yahoo.co.in>  
Subject  [mems-talk] Photolithography -  Resist peeling                                                                                                                                          

Hi,
       I am experiencing a problem in patterning on silicon-di-oxide
wafers; I am using SHIPLEY 1818 resist to get a thickness of 2.5 micron; 6
seconds of exposure time. After developing for 60 seconds, I observe, the
resist layer peels off; leaving no patterns on the wafer. Also I had
soft-baked the resist at 95 C for 2 minutes in hot-plate.
This seems strange to me, as a month ago, I had successfully transferred
the patterns on to silicon-di-oxide wafers.
I am using mylar film masks.
Please let me know, if any one had experienced similar problems before; and
if so, could you let me know suggestions to solve ?