#### aryajur

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I = K (Vgs-Vth)²(1+λ Vds)

For a PMOS I simulate and plot the IV curves for Vgs = 0.65V and Vgs = 0.8V for a 0.25um process (Vth0 = 0.558; uo=100e-4; Cox = 6.06e-3 => uo Cox = 0.606e-4).

From the curve when I calculate K I get the following results:

Vgs = 0.65; K = 3.09e-4

Vgs = 0.8 ; K = 1.19e-4

I understand that mobility is dependant upon Vgs. It decreases for increasing Vgs, uo being the high field mobility. But how does K become more than 0.606e-4, I assume this means that mobility from simulation is > the low field mobility uo.

If anybody has an idea why I get such a high value of K then please reply. Thanks.