Analytical Modeling of Output Conductance in Long-Channel Halo-Doped MOSFETs

In this paper, a detailed physical analysis and an analytical derivation of the degradation of the output resistance (R_out) observed in relatively long-channel laterally nonuniformly doped devices with halo implants are presented. Two-dimensional device simulations were performed, and the simulations show that the channel can be split into two uniformly doped transistors in series for the purpose of analysis. The lower doped bulk transistor is on the source side, while the higher doped halo transistor is toward the drain end. Based on this two-transistor analysis, a simple R_out degradation model is derived for implementation in a MOSFET compact model