Sonia,

Two suggestions:

1)  Make sure the back of the wafer is clean so you don't get vacuum leakage
around to the front of the wafer that will keep N2 from breaking the seal
with the mask and wafer.

2)  I also put a small piece of scotch tape on the chrome side of the mask
that extends a few millimeters into the wafer.  This will take that very
small edge out of focus and will allow N2 to help break the mask and wafer
seal.

Ad Hall
StarCryoelectronics
505-424-6454
[email protected]


-----Original Message-----
From: GARCIA BLANCO Sonia
Sent: Wednesday, November 09, 2005 3:07 PM
To: 'General MEMS discussion'
Subject: [mems-talk] BPR100 sticking to mask

Hi!

I wonder if somebody can help me: I am working with the resist BPR100 in
order to get a 100microns thick layer to perform a mask for nickel
electroplating. I am using contact lithography with a MA6 Mask aligner. My
problem is that the resist sticks to my mask everytime i try to expose it.

I manage now to get reasonably flat coatings and I remove the edge bead. i
thought it might be some excess of solvent still in the resist after the
bake so I tried a longer bake (3min on a 65C hotplate followed by a 15min
bake on a 95C hotplate). I have also tried to apply wax to the mask before
to perform the lithography and it still sticks to the mask.....

Anybody has some suggestions!!!