TEMPERATURE EFFECTS ON THE RESISTIVITY OF POLYCRYSTALLINE SILICON TITANIUM SALICIDE

The heating effects on the resistance of titanium salicide films formed on doped polycrystalline silicon materials have been characterized at temperatures ranging from 15 to 195-degrees-C. The resistance was also evaluated at various current densities in order to study the self-heating effects due to the supplied power. The polycrystalline silicon material was implanted with arsenic, boron, or phosphorus and then salicided. The resistivity of the salicide material was found to increase linearly with temperature at low current densities and deviates from linearity at higher operating current densities. An empirical model which relates the resistivity to temperature and current density has been developed for the above materials. The model can accurately predict the resistivity of salicided polycrystalline silicon material at a certain operating temperature and current density. A new expression for the temperature coefficient of resistance has also been developed, and experimentally verified under different operating conditions for n+ gate, n+ emitter, and p+ emitter salicided polycrystalline silicon materials.