Important: High voltage clarification

David Goldhaber-Gordon goldhaber-gordon at
Thu Mar 18 06:55:30 PST 2004

Hi all,

Thanks and congratulations are due to James for pushing so hard to get the
system up before he leaves for Germany.

I want to clarify one point: James probably meant that the voltages me may
use are 10-15 kV or 20.1 to 21 kV (i.e. 20100 to 21000 V). I point this out
since the actual numbers may be important and I’d hate for someone to
misunderstand and jeopardize the system for him- or herself and others.
James, please post a correction if I got this wrong. Also, could someone
comment on the proper procedure for getting up to those voltages? I'm not
sure that procedure has been uniformly agreed upon and communicated.



David Goldhaber-Gordon                         goldhaber-gordon at
Assistant Professor of Physics                 davidg at
Stanford University                            (permanent forwarding)
(650) 725-2047 (lab)                           (650) 724-3709 (office)

Address for letters or packages:               Administrative Associate:
David Goldhaber-Gordon                         Roberta Edwards
Geballe Laboratory for Advanced Materials      McCullough, Rm. 338
McCullough Building, Room 346                  Phone: (650) 723-8028
476 Lomita Mall                                Fax: (650) 724-3681
Stanford, CA 94305-4045                        email: redward at
-----Original Message-----
From: James Conway [mailto:jwc at] 
Sent: Wednesday, March 17, 2004 8:25 PM
To: John Cumings
Cc: Raith SNF Mailing list
Subject: Re: Raith is being qualified... Thread: Required Limits of keV
operation through 6APRIL2004 on RAITH 150

Please Everyone:

We would like to operate the system in a range between  10 - 15 KeV and/or
at 20100 to 2100 kV only. NOT 20 kV or higher than 21 kV.

 When  I return from Germany and with LEO field service we will perform
further testing on the column.  

Things are in good order and tomorrow I plan to put the system back into
green light mode as more measurements and imaging is completed

Stitching Mean + 3 sigma was 19 nm.

Thanks to everyone for your support during this challenging period,


John Cumings wrote:


Green light means 30 kV is okay.

I presume you mean yellow light, because 30 kV is not okay, correct?


     John Cumings
     cumings at 
     Postdoctoral Scholar
     Physics Department
     Stanford University                        

     office (650) 725-1025
     lab (650) 725-2047
     fax (650) 724-3681

     Geballe Laboratory for Advanced Materials
     239 McCullough Building
     476 Lomita Mall
     Stanford, CA 94305-4045
In message <4058B6CE.7060400 at>you write:
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I am most relieved to report that we are coming back into normal
operational status on the RAITH 150 system.<br>
This afternoon and evening we will be qualifying the system and working
with users whom are in crisis mode.<br>
We hope to go into green light mode in the next twelve hours.<br>
James Conway<br>


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