•  Welcome
 •  LEEM Basics
 •  LEEMs and PEEMs
 •  Movie Gallery
 •  Image Gallery
 •  Ask the Expert
 •  Tips and Tricks
 •  Tools and Analysis
 •  Conference Schedule
 •  Manufacturers
 •  Literature
 •  Open Positions
 •  Disclaimer
 •  Editorial
 •  Contact





is hosted by the University of


Life would be so easy with a screw like this...

which just shows that with the proper tools and knowledge even complicated tasks become easy. Here is a collection of LEEM and PEEM related tips that might be of interest for other users. If you have good advice for other researchers, send it to us and we might publish it here. 

Useful Equipment
Pyrometric Temperature Measurement
Reliable KF Flange Accessories
High voltage Insulation Transformer
VAT Valves


Ceramics and Refractory Metals

Needful Things
A Switched-Off Roughing Pump Makes Minimum Noise

Useful Equipment
subject: Pyrometric Temperature Measurement
Peter Kury (peter.kury@uni-essen.de)
(Top) The most elegant method to measure the sample temperature is infrared pyrometry. We haven΄t tried it at the LEEM yet, but we are working successfully with the IMPAC IGA 10 at all of our other machines.

IMPAC Electronic GmbH
Krifteler Str. 32
60326 Frankfurt/Main

subject: Reliable KF Flange Accessories
Peter Kury (peter.kury@uni-essen.de)
(Top) The KF flange accessories with the best price-performance ratio we have found are from

D. Katz GmbH
Godesberger Str. 5
50968 Koeln
Phone: 49-(0)221-34 00 316
Fax: 49-(0)221-34 00 617

subject: High Voltage Insulation Transformer
Peter Kury (peter.kury@uni-essen.de)
(Top) For the in-situ e-beam sample heating it's necessary to let the power supplies float at for example 15kV, so a high voltage insulation transformer is needed. The price for such a transformer is pretty high, if it's ordered at a company that's specialized in high voltage power supplies like Bertan or FUG.

I found a transformer company that offered a good working 20kV/500VA transformer at a price of less than €100; it's Breimer-Roth Transformatorenwerke. They built the transformer on demand within one week.



subject: VAT Valves
Peter Kury (peter.kury@uni-essen.de)

Everybody who wants to use the nice VAT MonoVAT UHV valves ( DN 40CF-F, No. 01032-CE01) at a LEEM should pay attention to their high magnetism. The company points out, that even though there were no magnetic materials ( except for the bearing ) used,  some parts became magnetic due to the production process.

We reduced the magnetism by exchanging the steel bearing balls with SiN ceramics of the same diameter (5mm). Even small amounts like 100 pcs. are available at


CFI - ceramics for industry

a BAYER company

Oeslauer Str. 35

96472 Roedental



The price is about €1.50 each and 21 balls per valve are needed. SiN balls, 5.0mm, grade 5, P0, No. 13115, material N8201

subject: Ceramics and Refractory Metals
Mark Reuter (mcr@us.ibm.com)
(Top) Jim Hannon told me about this small company that you might find useful. The company seems to be one guy named Bernard Scheiff. Send him a fax with your name and address telling him you are interested in high temp. metalsand ceramics and he will send you a small catalogue.

He has Tungsten, Molybdenum, and Tantalum sheet, screen, wire, rod, screws, nuts etc. and also Alumina screws, nuts, and washers.

Thermo Shield
722 Orange Ave
Los Altos, CA 94022
tel: (650) 941-5230
fax:(650) 941-2568

Needful Things
subject: A switched-off Roughing Pump Makes Minimum Noise
Peter Kury (peter.kury@uni-essen.de)
(Top) Most of the rotational roughing pumps used for the coarse vacuum produce a lot of mechanical and electrical noise. To be able to switch them off during measurements we are using beer barrels ( no joke ) as pressure reservoirs. Those barrels are made of stainless steel, having a volume of 50 liters and a 2"14tpi connection. Everybody who is interested in drawings for the adaptor barrel-to-KF should send an EMail to me.

The company we got our barrels from is

Blefa GmbH & Co KG
Huettenstrasse 43
57223 Kreuztal

The barrels' type was No. 01001758 at a price of €50 each.
I can highly recommend to use such reservoirs, the difference is really enormous!



University of Duisburg-Essen | AG Horn-von Hoegen


Au (5x3.2) Reconstruction Domains grown on Si(111). Courtesy of F. Meyer zu Heringdorf and R. Tromp, IBM.

Growth of Lead on Cu(111). Courtesy of Gary Kellog, Sandia

PEEM Images of Pentacene Islands on Si. Courtesy of F. Meyer zu Heringdorf and R. Tromp, IBM