How to get mobility values?

[cheenu_2002]

Hi,
Can anyone tell me how to get the electron and hole mobility, Cox values for a particular process technology.

 

[snafflekid]

Mobility is related to doping concentration and I think you would just read it off a graph.

**broken link removed**

 

[cheenu_2002]

But I would like to know how to get these values for a particular process. I think it will vary across the fabs. For eg. if I use TSMC 45nm process, where can I get these values (so that I can use it for ahnd calculations of my design). Is there any specific file in the pdk that contains these info?

 

[dick_freebird]

You do not need bulk mobility (which could be found in any
semiconductor fundamentals text, I expect) but the MOS
surface mobility. That is a different thing, relating to the
particulars of the interface (states / traps, roughness,
dopant accumulation / oxide uptake and so on).

If you are trying to model the device, begin with the aspects
that are most physical and most empirically accessible
(for example, Cox can be had by direct measurement
electrical or optical readings, true gate length by delta-L
test structures and so on) and arrive at the less accessible
params by back-fitting. Like, you can get VT0 by electrical
data & fit that, you got your realistic oxide geometries
and a close enough Cox from that, so then u0 falls out of
the I=u0*Cox*(Vgs-VT)**2 fit.

A foundry PDK ought to have the models for you, all done.
But they probably want intellectual property / nondisclosure
agreements. If you have the PDK then start at the top and
just dig for "spectre" or "model" keywords in files.