Reconsideration of effective MOSFET channel length extracted from channel resistance

Effective channel length (LEFF) for the MOSFET having both “halo” and “extension” in its channel is extracted using “channel resistance method” (CRM). It is found that LEFF is strongly affected by the halo dose and gate voltage. As the halo dose is decreased to zero, LEFF converge the reasonable value and that for the MOSFET having uniform channel is uniquely determined, even if various sample MOSFET sets are used. Taking this property into consideration we propose new channel length definition, which is constant and obeys the classical current equation for the MOSFET with uniform channel, in order to provide the common channel length interpretation for both design and technology engineers.