Electron diffraction with ten nanometer beam size for strain analysis of nanodevices

Abstract

A method to perform nanobeam diffraction (NBD) in a transmission electron microscope with high spatial resolution and low convergence angle is proposed. It is based on the use of a properly fabricated condenser aperture of 1 mu m in diameter, which allows an electron beam about 10 nm in size to be focused on the sample, with a convergence angle in the 0.1 mrad range. Examples of NBD patterns taken in an untilted cross section of a silicon device are shown. Their quality is adequate for spot position determination and hence to obtain, in principle, quantitative strain information. (C) 2008 American Institute of Physics. {[}DOI: 10.1063/1.3003581]