Subject: Beam blanker switch
From: Arash Hazeghi <>
Date: Wed, 09 Apr 2008 01:55:43 -0700

Last night I spent more than 2 hours on the tool trying to figure why  
the beam would unblank itself when using the move command (with beam  
blanked), scanning anything in the position list or doing align write  
field. I was not able to do manual align write field because the beam  
would unblank itself, machine would go under SEM control and no image  
was acquired as a result. I tried automatic marks, the beam was  
unblanked again exposing all of my wafer and switching to int mode on  
its own. So I gave up, on the way out I talked to the next user about  
this, after looking at the control rack he figured the manual beam  
blanker switch was in lower position. I didn't know about this switch  
and as far as I know users are not supposed to change these settings.  
My time was wasted and my wafer was destroyed because an expert user  
did not remember to reset the switch. Please be more considerate.