Overlooked interfacial silicide-polysilicon gate resistance in MOS transistors

We discuss a previously overlooked gate resistance (R_g) component in silicided polysilicon-gate metal-oxide-semiconductor field-effect-transistors (MOSFETs). Since the high-frequency properties depend critically on R_g, this has motivated the recent addition of a resistive gate input in the BSIM3v3 MOSFET model. Our TLM results show that the contact resistance between silicide and polysilicon, built into the gate of a typical MOSFET, is of the same magnitude as the silicide sheet resistance. This contact resistance affects model scaling and will dominate R_g in narrow-width and short-channel MOS transistors