The influence of silicide formation on the barrier height of Ti/Si MIS Schottky barriers
De Bosscher, W × Van Meirhaeghe, RL Hanselaer, Peter Caenepeel, L Laflere, WH Cardon, F #
Iop publishing ltd
Semiconductor science and technology vol:1 issue:6 pages:376-382
Ti/Si MIS diodes were made by evaporating Ti on a hot substrate at a temperature T,, which could be varied between room temperature and 760 degrees C. It was found that for T-s < 300 degrees C the Schottky barrier height phi B changed with T-s and also depended on the pre-metallisation treatment of the silicon surface. Between 300 degrees C and 500 degrees C, phi B remained independent of T-s. These results could be explained by the reaction wherein titanium converts the silicon oxide into titanium oxide and titanium silicide. Further support for this model was obtained from Auger measurements. Between 500 degrees C and 600 degrees C a complete conversion of both the interface layer and the Ti top layer into silicide occurred and oxide was no longer present at the interface. For T-s > 600 degrees C, a phi B typical for a titanium disilicide/Si contact was measured.