Room and low temperature electrical measurements for the interface characterization of titanium disilicides on silicon from multilayer titanium/silicon structures

Abstract

The interface of titanium disilicides TiSi2 on silicon formed by electron gun evaporation of silicon/titanium multilayers and subsequent annealing is characterised using current-voltage measurements on specially prepared Schottky diodes in the whole temperature range from room temperature down to 77K. In particular, the influence of the bilayer SiITi thickness ratio, ranging between 2 and 3, on the barrier height of the diodes is studied and compared with the case of a diode formed by deposition of a single titanium layer and further annealing. The activation energies derived from the low temperature measurements have shown that the interface of the sample prepared with single layer deposition is more rough than the case of the sample prepared with deposition of multilayers using a bilayer thickness ratio Si/Ti=2.5 which is close to the calculated value for the stoichiometric films.