Test structures for study of electron transport in nickel silicide features with line widths between 40 nm and 160 nm

A new test structure has been designed and fabricated for the investigation of the effect of linewidth scaling on electron transport in nickel mono-silicide features. In the fabrication process, nickel silicide (NiSi) features were formed by annealing a nickel coating that was deposited on single-crystal silicon features that were as narrow as 150 nm and had vertical and nearly atomically flat sidewalls. The features were patterned on [110] silicon-on-insulator wafers with i-line lithography that replicated test structures from which voltage/current (V/I) measurements could be extracted. Subsequently, the patterning of single-crystal features with direct-write electron-beam lithography has been developed in order to facilitate the future reduction of the linewidths of NiSi features having a highly controlled surface microstructure to below 40 nm.