Hello,

why don't you try two different masks?

As you rightly said: every-time you finish exposing a wafer in the MA6, it will
release the wafer so it is always hard to load the wafer to the light twice
without the wafer been released.

I will suggest a two mask solution.

first mask + second mask shifted by how many microns you want. Both adjusted by
the same adjustment mark.

regards
Nimo


________________________________
From: Ciro Chiappini 
To: General MEMS discussion 
Sent: Thu, February 17, 2011 12:43:11 AM
Subject: [mems-talk] K. SUSS MA6 Double exposure

Hello

I need to run a double exposure in vacuum contact mode with a K. Suss
MA6 tool. The two exposures must be shifted by roughly 5 microns, but
I don't have a way to visually align them.

The process I was going to run was: load, WEC, bring wafer to contact,
expose, bring back to alignment separation, slide 5um on the
micromanipulator, bring to contact, expose, unload.

If I run the standard exposure sequence, after the first exposure the
tool requires to unload the wafer (and thus I'll lose my rough
alignment)

The easiest way I see to accomplish this is to use the light intensity
check button on the tool, that allows to operate the UV light
independently. Unfortunately that button is not functional while a
substrate is present.

Has anyone ever been able to override the standard exposure sequence on an MA6?

I Have easily run this protocol on an EVG620 with the low level IO,
but I need to expose 600nm features and our EVG620 cannot resolve
them.

Thanks for your help.