High spatial resolution strain measurement of deep sub-micron semiconductor devices using CBED

Mechanical stress due to trench isolation and contact etch-stop-layers (ESLs) has been reported to show a marked influence on the electron and hole mobility of nanoscaled MOSFETs. Conventional tools such as micro-Raman spectroscopy and X-ray diffraction for measuring strain are limited in resolution. By using convergent beam electron diffraction (CBED) with nanometer spatial resolution, we have evaluated the mechanical stress induced in deep sub-micron devices by different etch-stop-layers (ESLs) and have demonstrated that the stress along the channel region can be engineered through the implementation of different ESLs.