Application of Variable C_S HRTEM to the Study of Nanoscale Structures

Abstract

As nanoscale systems are increasingly incorporated into industrial products, an understanding of defect behavior and interfaces in these materials is critical. Because of the inherently small dimensions of the "nano" regime, characterization of nanoparticle-based systems demands high resolution. The transmission electron microscope (TEM) is uniquely suited for this task, although its resolution is limited by the aberrations present in electromagnetic lenses [1].

Experimental investigations into the formation of nanoparticles in a∕nc-Si:H thin films

“…Careful analysis of such images has shown that the Si nanocrystals are diamond cubic in structure with a lattice constant consistent with bulk Si. 45,46 Additionally, some nanoparticles contained twin boundaries and stacking faults characteristic of Si. 45,46 No alternative structures of Si have been observed in these films, as have been reported in other studies.…”

“…45,46 Additionally, some nanoparticles contained twin boundaries and stacking faults characteristic of Si. 45,46 No alternative structures of Si have been observed in these films, as have been reported in other studies. [47][48][49] To further elucidate whether the nanocrystals observed in the a / nc-Si: H films are indeed formed by nucleation in the gas phase and subsequently deposited into the film, experiments were performed using the thermophoretic force to either allow or prevent particle deposition on the substrate.…”

Observation of Si nanocrystals in a/nc-Si:H films by spherical-aberration corrected transmission electron microscopy

“…However, conventional HRTEM imaging usually superimposes the image contrast of the nanocrystallites on that of the surrounding amorphous matrix. This complicates image analysis greatly, as the nanocrystals must be subjectively distinguished from the background amorphous intensity [28][29][30][31].…”

Observation of Si Nanocrystals by Spherical-Aberration Corrected Transmission Electron Microscopy

“…However, conventional HRTEM imaging usually superimposes the image contrast of the nanocrystallites on that of the surrounding amorphous matrix. This complicates image analysis greatly, as the nanocrystals must be subjectively distinguished from the background amorphous intensity [4].…”