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Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.

TEM image acquisition is subject to limitations in resolution imposed by the physics of the position-sensitive detection process. in existing on-line digital cameras detection consists of scintillation, image transfer and photon detection by a CCD. Scintillator resolution is governed primarily by the incident beam energy. Material parameters affect the resolution only weakly. Some improvement can be made with a thin transmission scintillator. Still, backscatter of electrons from below can form a noisy background. Optical transfer resolution also has an important effect on overall camera system resolution. Leakage of light within scintillator, between fibers, at interfaces, and the inherent resolution loss due to binning into a finite pixel all contribute to optical resolution loss. This point spread function is narrower than the electron point spread function above 100kV but has an affect at all voltages. Long-range light leakage (psf tail) affects the background noise in diffraction work where there is often a 10e6 ratio between central peak and diffraction spot of interest. Thus, the number of resolved pixels in a TEM image detector is limited by the area of the detector, the effective thickness of the scintillator and the quality of the image transfer.Gatan has developed several improvements which will address both electron and lightoptical resolution loss.

Recent progress in High Resolution Transmission Electron Microscopy makes it possible to investigate crystalline materials by phase contrast microscopy with a resolution close to the 80 pm information limit of a 300 kV field emission microscope'"". A reconstruction of the electron exit wave from a focal series of lattice images converts the recorded information into interpretable resolution. The present contribution illustrates some recent applications of this technique to interfaces.Fig. 1 shows a reconstructed electron exit wave of a heterophase interface between GaN and sapphire. The experiment takes advantage of three factors: First, we resolved the GaN lattice inprojection, which requires at least 0.15 nm resolution. Theprojection eliminates the stacking fault contrast that usually obscures lattice images in the commonly recordedprojection. Thus, image interpretation is drastically simplified. Second, all atom columns at the interface and in the sapphire are resolvable with a smallest projected aluminum - oxygen spacing of 85 pm in the sapphire.

Aside from the electron column, there are many factors that determine image quality in an ultra high resolution Field Emission Scanning Electron Microscope (FESEM). To obtain quality images, the operator must minimize sample contamination and be able to select the appropriate signal generated from the sample surface. Hitachi has developed a new in-lens FESEM that both minimizes surface contamination and improves signal efficiency.Sample contamination is reduced by incorporating an oil free vacuum system, consisting of a 300 1/s turbomolccular pump and a 200 1/min scroll pump. For demanding applications, an additional 50 1/s turbomolccular pump can be added to back the main high vacuum pump. Furthermore, sample contamination caused by electron beam irradiation has been reduced by employing a high speed electrostatic beam blanking system. By blanking the beam during scan retrace (flyback), the electron dose accumulated on the sample can be minimized.