[SOLVED] cross section of an exponential cell

[preethi19]

Hi i am trying to draw a 3d diagram for an exponential cell having two pmos transistors.


when i was seeing some examples i came across nmos and pmos laid on the same substrate as show in fig below


We can see in this image that nmos and pmos has an isolation. So now in my case i cant lay those two pmos together becoz they both have different bulk potential. So say on one substrate i draw two nwell for each pmos transistor with some distance in between these nwell do i need an isolation layer like the one with nmos and pmos??? Pls help. Thank you!!!

 

[erikl]

... i draw two nwell for each pmos transistor with some distance in between these nwell
do i need an isolation layer like the one with nmos and pmos?

No you don't need it. Just enough spacing to suppress a possible lateral npn BJT action between the 2 nwells.