Synthesis of nanostructured thin films for resolution and diffraction/ camera length calibration of transmission electron microscopes

Abstract

TEM is one of the highly sophisticated, sensitive and accurate tool for carrying out microstructural detailed investigations of the materials in terms of their crystallographic structure, lattice imaging, phase identification, variety of defects present, particle size and shape analysis etc. at the nano scale level. The accuracy and efficiency of electron microscope depends upon the magnification and resolution of the instrument. Evaporated films of gold, magnesium oxide, and thallium chloride make excellent calibrating substances since they have d (interplaner spacing) values accurately determined by x-ray diffraction.  In the present investigations, preliminary studies on thermally evaporated thin films of high purity tin and silver  deposited on KCl substrate and carbon coated Ni/Cu TEM grids under high vacuum conditions (of the order of 10^-6 torr) have been undertaken. These films were characterized for particle shape, size, lattice imaging by using TEM and HRTEM (High Resolution Transmission Electron Microscope). Selected area electron diffraction pattern  The deposition process of nanoparticles was precisely monitored to get high quality, stable and with repeatable and uniform sized particles. The aim of the study is to optimise the synthesis parameters to deposit uniformly distributed nano size gold particles using thermal evaporation technique which will be further used as a standard sample for the calibration of camera length and resolution of  TEM.