DIFFERENTIAL SILICIDE THICKNESS FOR ULSI SCALING

摘要

We investigate the formation of CoSi_2 over a wide temperature range (275-450C for the first of a 2-step formation), and show that, for a given anneal, it is possible to obtain significantly thicker silicides on poly than on substrate Si. By selecting appropriate time-temperature combinations, one can obtain thickness differences of 50% or more. This can be useful for obtaining low sheet resistance gates while minimizing silicide spiking in the junctions.