Raith not working - beam blanking problem

[Kenneth Brian Crozier]

hi everyone,

this is to clarify the earlier emails.

James and I had a more detailed discussion this morning on the problem and 
it seems that the problem is indeed that the Raith blanking is not 
functioning correctly.  This does not affect all users as the background 
current (with the beam supposedly blanked) will only be enough to expose 
the resist for patterns that take a long time to write (such as mine, which 
takes 90 min).

Therefore it might be perfectly OK for your patterns !

Note that the problem is not due to charging as the silicon nitride layer 
is very thin (200 nm).  Also, exactly the same substrates (deposited in the 
same batch) with exactly the same patterns and exactly the same resist 
(ZEP) used to work fine.

Also, note that other users (such as Arvind) have also experienced the same 
problem.  It would be great if anyone else who has experienced a similar 
problem could also report it.

James has been extremely helpful on this one and is attempting to find a 
way to fix it.

best wishes,
Ken