mikki33 wrote on Jun 11th, 2006, 8:55am:NF and M are interchangable paraneters. You may use or one or another.
Yikes! That is a dangerously untrue statement, and it's a little hard to decipher the truth from what you wrote later.
"m" is generally defined as the "number of (identical) parallel devices" -- and implemented in the simulator, rather than in the model source code that one might get from Berkeley.
"nf" is, as Bernd wrote, a way of specifying some geometry information pre-layout.
But it's important to know that
m1 d g 0 0 nch w=1u l=0.18u m=100
is definitely not the same as
m1 d g 0 0 nch w=1u l=0.18u nf=100
The first will have 100 devices, each with a drawn width of 1u. The second will have 100 poly gates each with a width of 0.01u.