Broad ion beam milling of focused ion beam prepared transmission electron microscopy cross sections dor high resolution electron microscopy

A technique is presented which enables both sides of a transmission electron microscopy cross section specimen prepared using a focused ion beam system to be milled using a broad ion beam source. The cross section specimen is prepared using the "lift-out" technique and is placed onto a copper mesh grid with 10 mum sized holes. The upper face of the cross section specimen is first milled in a broad ion beam source, after which a micromanipulator and needle is used to turn it over so that the other side can be milled. The use of a broad ion beam source enables lower incident beam energies and angles of incidence to be used than is currently possible in a commercial focused ion beam system. The technique can be used to decrease the thickness of the damage layer at the sidewalls of a focused ion beam prepared cross section specimen and to reduce its thickness in a controlled way. (C) 2001 American Vacuum Society.