First experiments of selected area nano-diffraction from semiconductor interfaces using a spherical aberration corrected TEM.

Selected area diffraction (SAD) from localized areas that are approximately 20 nm in diameter has been demonstrated for the first time using a spherical-aberration-corrected transmission electron microscope (Cs-corrected TEM). We have succeeded in obtaining sharp diffraction patterns from well-defined areas on both sides of the interface between a Ti-Si-Ge alloy and Si0.54Ge0.46. The errors in the area selection by an SAD aperture are reduced to <2 nm by the Cs-correction. The applications of this technique in studies of nanometer-sized materials are discussed.