A self-aligned vertical Kelvin test structure to measure contact resistivities of Al and Ti on Si

Abstract

A self-aligned vertical Kelvin test resistor structure, which not only eliminates the horizontal current crowding but also avoids the misalignment error, is proposed and used to measure p/sub c/ of Al and Ti on Si. For the Al(1%Si)/n/sup +/-Si contact system, a specific contact resistivity of 1*10/sup -7/ Omega -cm/sup 2/ has been measured. For the TiSi/sub 2/ contacts, the TiSi/sub 2/(direct-reaction)/n/sup +/-Si contact offers a lower p/sub c/ than that of the coevaporated TiSi/sub 2//n/sup +/-Si contact, and p/sub c/ does not change even after the contacts are annealed to 900 degrees C.<>