Optimum location of silicide/Si interface in ultra-thin body SOI MOSFETs with recessed and elevated silicide source/drain contact structure

Optimization of the series resistance of silicide contact structure in ultra-thin body (UTB) silicon-on-insulator (SOI) MOSFET with elevated source/drain (S/D) is examined through theoretical analysis and 2-dimensional simulation. It is found that the optimum silicide/Si interface position, which exhibits lowest parasitic series resistance, can be located at inside of SOI layer under the surface as the effective contact length is scaled down further below 100 nm regime. The closed-form analytical expressions derived from modified transmission line model principle provide a guideline for optimum design of silicide thickness and contact parameters in self-aligned silicide technology.