Crystalline defect analysis in epitaxial SiGe layer using site-specific ECCI-STEM.

Electron channeling contrast imaging (ECCI) is a powerful technique to characterize the structural defects present in a sample and to obtain relevant statistics about their density. Using ECCI, such defects can only be properly visualized, if the information depth is larger than the depth at which defects reside. Furthermore, a systematic correlation of the features observed by ECCI with the defect nature, confirmed by a complementary technique, is required for defect analysis.

Application of electron channeling contrast imaging to 3D semiconductor structures through proper detector configurations.

Nowadays electron channeling contrast imaging (ECCI) is widely used to characterize crystalline defects on blanket semiconductors. Its further application in the semiconductor industry is however challenged by the emerging rise of nanoscale 3D heterostructures. In this study, an angular multi-segment detector is utilized in backscatter geometry to investigate the application of ECCI to the defect analysis of 3D semiconductor structures such as III/V nano-ridges.

Enhancing the defect contrast in ECCI through angular filtering of BSEs.

In this study, an annular multi-segment backscattered electron (BSE) detector is used in back scatter geometry to investigate the influence of the angular distribution of BSE on the crystalline defect contrast in electron channeling contrast imaging (ECCI). The study is carried out on GaAs and Ge layers epitaxially grown on top of silicon (Si) substrates, respectively. The influence of the BSE detection angle and landing energy are studied to identify the optimal ECCI conditions.

Non-destructive characterization of extended crystalline defects in confined semiconductor device structures.

Semiconductor heterostructures are at the heart of most nanoelectronic and photonic devices such as advanced transistors, lasers, light emitting diodes, optical modulators and photo-detectors. However, the performance and reliability of the respective devices are often limited by the presence of crystalline defects which arise from plastic relaxation of misfit strain present in these heterogeneous systems. To date, characterizing the nature and distribution of such defects in 3D nanoscale devices precisely and non-destructively remains a critical metrology challenge.