Submicron imaging of buried integrated circuit structures using scanning confocal electron microscopy

Two-dimensional images of model integrated circuit components were collected using the technique of scanning confocal electron microscopy. For structures embedded about 5 mum below the surface of a silicon oxide dielectric, a lateral resolution of 76+/-9 nm was measured. Elemental mapping via x-ray emission spectrometry is demonstrated. A parallax analysis of images taken for various tilt angles to the electron beam allowed determination of the spacing between two wiring planes. The results show that scanning confocal electron microscopy is capable of probing buried structures at resolutions that will be necessary for the inspection of next-generation integrated circuit technology. (C) 2002 American Institute of Physics.