Limitations of shift-and-ratio based L-eff extraction techniques for MOS transistors with halo or pocket implants

The shift-and-ratio method has been considered as one of the most accurate and consistent techniques for extracting the effective channel-length of th e MOS transistor. This method assumes the effective mobility of a long chan nel and a short channel transistor to be equal. Scaling down the MOS transi stor urges the need of including halo (or pocket) implants in the fabricati on process. Due to this implant, however, the short channel MOSFET features a degraded effective mobility compared to the long channel reference devic e. This affects the channel-length extraction and results in unrealistic hi gh values for the extracted effective channel-length for deep submicron tra nsistors with high-dose halo (or pocket) implants.