During the last 5 years, the semi-conductor industry has enhanced device performances by scaling down the feature sizes and by introduction of new technologies. Transmission electron microscopy with high resolution images (HREM) has become an indispensable tool for analyzing devices structure at nanoscale, for failures analysis, defects review and manufacture controlling. In parallel to this progress on the devices, the sample preparation techniques for MET compatible with the requirements of the industrial world were developed and open new prospects. In this paper, we present these techniques of sample preparation. Then we show examples in what high resolution images make it possible to answer industrial problems.