Improved Prediction of Length/Temperature-Dependent Impact Ionization Induced Body Current Based on an Accurate Saturation Drain Voltage Model

摘要

The length/temperature-dependent body current I_B in deep submicron LDD pMOSFETs is investigated, based on an improved saturation drain voltage (V_(SDsat)) extraction algorithm and model. The accuracy of V_(SDsat) is shown to have a direct influence on the extraction of the impact ionization parameters (A_i,B_i, l_c) and prediction of I_B. Approximations of impact ionization constants (A_i, B_i) and their linear dependency on temperature have been verified, for the first time, to be inadequate as the device length scales to deep submicron regimes. With a new proposed I_B model, an improved prediction of I_B for a wide range of biases, temperatures and channel lengths is also presented.