Chemical and structural analysis of etching residue layers in semiconductor devices with energy filtering transmission electron microscopy

The use of an energy-filtering held emission gun transmission electron micr oscope (CM30 FEG Ultratwin) allows, apart from imaging morphologies down to nanometer scale, the fast acquisition of high-resolution element distribut ions. Electrons that have lost energy corresponding to characteristic inner -shell loss edges are used to form the element maps. The production of Ultr a Large-Scale Integration (ULSI) devices with dimensions below 0.25 mum req uires among others the formation of a multilayer metallization scheme by me ans of repeatedly applying the deposition and etching of dielectrics and me tals. In this work the evolution of the surface chemical species on etched Al lines in a post-etch cleaning process has been investigated by energy fi ltering transmission electron microscopy, with the aim to understand the ro le of each process step on the removal of the etching residues. (C) 2001 El sevier Science Ltd. All rights reserved.