A new methodology for evaluating VT variability considering dopant depth profile

A new normalization method of V_T variability in terms of dopant depth profile is developed and applied to measured variation data of MOSFETs with four types of channel dopant (B, Sb, P, As) with different depth profiles. The normalized coefficient shows a constant value indicating the validity of the method. However, it is shown that only B has much larger coefficient, suggesting B has some extra origins of variability.