Silicon Device Backside De-Processing and Fault Isolation Techniques

This article presents methods that enable one to consistently, uniformly and quickly remove substrate silicon from units without imparting damage to the structure of interest. It provides examples of electron beam probing and backside nano-probing techniques. The electron beam probing techniques are E-beam Logic State Imaging, Electron-beam Signal Image Mapping, and E-beam Device Perturbation. Backside nano-probing techniques discussed include: Electron Beam Absorbed Current, Electron Beam Induced Resistance Change, four terminal resistance measurements, resistive gate defect identification, and circuit editing. The article also presents methods to prepare electron beam probing samples where some remaining silicon is required for the transistor functions and transmission electron microscope samples from units where the substrate silicon has been partially or completely removed.