The composition of InGaN/AlN/GaN MQWs nano structure is anlayzed by STEM/EDS. The concentration of nitrogen in GaN materials is usually lower than that of gallium for specimen thickness larger than 50 nm due to low penetration ability of N K X-rays (0.392 KeV). The concentration of indium in the InGaN quanturm wells obtained by STEM/EDS analysis is always much lower its real value. This concentration dilution in this 3 nm structure results from the effect of electron beam broadening, and can be improved to a certain level by reducing specimen thickness, C2 aperture, and dwell time, with a sacrifice in signal intensity.

Traditional plane-view TEM images, which have large fields of view and are usually used to check the existence of dislocations, cannot tell whether a dislocation goes through the p-n junction or not. While XTEM images tell the local depth of a small part of a dislocation only, other methods have to be developed to explore how a dislocation goes in the substrate. In this article, the authors have modified the technique of stereo TEM, which was used to study the 3D shapes of precipitates, to study how a dislocation runs in the Si substrate. Three images recorded after tilting the TEM sample were used for measuring the dislocation depth profile. The distances between a few chosen points on the dislocation and the reference line were measured from above three images. Results suggested that the depth profiles of dislocations in the Si substrate can be accurately determined by stereo TEM.

Strained silicon induced by the CMOS device process has been considered an important technology for improving the performance of MOSFETs by increasing local carrier mobility in the current channel. In order to evaluate the feasibility of using convergent beam electron diffraction (CBED) in lattice strain determination, high-order Laue zone (HOLZ) lines inside the center disc of a CBED pattern with specific zone axes were kinematically simulated. The intersecting HOLZ lines shift was plotted against the lattice parameter for the determination of uniaxial strain.

A 300 keV TEM equipped with an EELS and energy selected imaging (ESI) system has proven to be a necessary and powerful analytical tool for R&D and failure analysis support. The advantages and the efficacy of this advanced elemental mapping technique can be optimized when the TEM is operated correctly. Variants of ESI, elemental mapping, jump-ratio mapping, and pre-edge imaging have been adapted to explore root causes of different type of failures in semiconductor manufacturing.