Metallography of very large scale integrated circuits

Three metallographic preparation techniques are described which provide a wide investigation spectrum of integrated components. The thin-film composition of chips with diverse insulation and metallization films can be revealed in the optical microscope using the oblique section technique. Precipitation phenomena of silicon at the phase boundaries, in the metallization matrix and at the grain boundaries of the metallization are described. Copper-containing particles precipitated as a result of electromigration transport phenomena in AlSi(1)Cu(4) or AlSi(0.5)Cu(0.5) metallization lines are detected metallographically and analytically (WDX, EDX). The pores at the negative pole as well as the location of the Al2Cu precipitates in the metallization lines could be explained by material transport due to electromigration.