Connecting small-angle diffraction with real-space images by quantitative transmission electron microscopy of amorphous thin-films

We have explored quantitative methods to study projected density fluctuations on the scale 0.5–2 nm in amorphous thin-films using weak phase object transmission electron microscopy. A useful method includes quantitative analysis of electron images and their Fourier amplitudes, essentially combining small-angle scattering analysis and high-resolution imaging from the same microscopic region. By comparing the Fourier spectra of differently prepared SiO2 specimens, we show that clear differences between similar-looking samples can be detected quantitatively, and defect sizes and densities can be measured. Further development of this technique may hold significant value for researchers working to understand small-angle diffraction and for those investigating the performance of microelectronic thin oxides.