Current-induced structural modification of silicon-on-insulator nanocircuits

Abstract

Silicon-on-insulator (SOI) materials are considered the next form of Si for extending the metal–oxide–silicon technology. Here, we report the electrical study correlated with the topographical modification of nanostructures built on 20-nm-thick SOI. At current densities around 3×106 A cm−2, we noticed an irreversible modification characterized by formation of nanochannels and failures at n+n contacts. The origin of these channels can be attributed either to hydrodynamic diffusion of positive Si ions or to momentum exchange with holes created by impact ionization at high electric field (105 V/cm). We show also that the heating of the circuit plays an important role in the process.