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pbs681 New Member Offline Posts: 8	physical parameter in bsim3v3 Feb 17^th, 2006, 6:48pm Can somebody help me to list all the phycical parameter in bsim3v3? thx
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Paul Community Fellow Offline Posts: 351 Switzerland	Re: physical parameter in bsim3v3 Reply #1 - Feb 20^th, 2006, 12:19pm You can find the model documentation on the official web site: http://www-device.eecs.berkeley.edu/~bsim3/get.html Hope this helps Paul
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pbs681

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Re: physical parameter in bsim3v3
Reply #2 - Feb 21^st, 2006, 4:28am

Paul wrote on Feb 20^th, 2006, 12:19pm:

You can find the model documentation on the official web site:
http://www-device.eecs.berkeley.edu/~bsim3/get.html

Hope this helps

Paul

Thanks Paul for the website. But what I mean here is that, from more than hundred parameters in MOS model, which one is carrying physical meaning... ie tox, cj.... we know that these parameters (MOS model) are mixing of empirical and physical parameters

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bernd Senior Member Offline Posts: 229 Munich/Germany	Re: physical parameter in bsim3v3 Reply #3 - Feb 21^st, 2006, 5:12am Maybe `spectre -help bsim3v3` helps, if you are a Spectre user. Bernd
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Geoffrey_Coram

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Re: physical parameter in bsim3v3
Reply #4 - Feb 21^st, 2006, 6:26am

[quote author=pbs681 link=1140230903/0#2 date=1140524905]Paul wrote on Feb 20^th, 2006, 12:19pm:

But what I mean here is that, from more than hundred parameters in MOS model, which one is carrying physical meaning... ie tox, cj.... we know that these parameters (MOS model) are mixing of empirical and physical parameters

pbs681 -
I don't think your question is well posed. For example is CJ really physical? One could argue that it is a fitting parameter for the capacitance per area of the source/drain diffusion; the junction itself is probably not abrupt nor linearly graded. I think there's a continuum of sorts from the "truly physical" parameters like TOX to the "strictly empirical" parameters like VOFFCV. And many parameters probably have default values that are computed from physical values, but you can tweak them to fit the measurements better. (Eg, CGBO has a default value of 2*DWC*COX, which is physical, but what if you change it to 1.8*DWC*COX?)

Probably your best bet would be to find an extraction guide for BSIM3, which would tell you what parameters you could fill in "good values" for from physical process information.

-Geoffrey

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If at first you do succeed, STOP, raise your standards, and stop wasting your time.

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pbs681

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Re: physical parameter in bsim3v3
Reply #5 - Feb 22^nd, 2006, 3:45am

[quote author=Geoffrey_Coram link=1140230903/0#4 date=1140531974]pbs681 wrote on Feb 21^st, 2006, 4:28am:

Paul wrote on Feb 20^th, 2006, 12:19pm:

But what I mean here is that, from more than hundred parameters in MOS model, which one is carrying physical meaning... ie tox, cj.... we know that these parameters (MOS model) are mixing of empirical and physical parameters

pbs681 -
I don't think your question is well posed. �For example is CJ really physical? �One could argue that it is a fitting parameter for the capacitance per area of the source/drain diffusion; the junction itself is probably not abrupt nor linearly graded. �I think there's a continuum of sorts from the "truly physical" parameters like TOX to the "strictly empirical" parameters like VOFFCV. �And many parameters probably have default values that are computed from physical values, but you can tweak them to fit the measurements better. �(Eg, CGBO has a default value of 2*DWC*COX, which is physical, but what if you change it to 1.8*DWC*COX?)

Probably your best bet would be to find an extraction guide for BSIM3, which would tell you what parameters you could fill in "good values" for from physical process information.

-Geoffrey

Hi Geoffrey,
I totally agree with you. My question was not well posed since I am still new in this field. That is what I mean. Sorry for that. Anyway I have question regarding Cj. In order to extract the Cj, we draw special test structure that include the Cj requirement extraction, ie area intensive and prephery intensive test structure. That means, Cj is directly extracted from the structure and not from the calculation. That is why I am reffering this parameter as a physical parameter. Is it correct?

Where can I find an extraction guide for BSIM3. Really appreciate if anybody can help on this.

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Geoffrey_Coram Senior Fellow Offline Posts: 1999 Massachusetts, USA	Re: physical parameter in bsim3v3 Reply #6 - Feb 24^th, 2006, 6:21am This web page http://www.eecs.berkeley.edu/IPRO/Software/Catalog/Description/bsim3v2.0.html says that an extraction guide for BSIM3 is available for $1. You may find it for free if you spend enough time with Google.
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pbs681 New Member Offline Posts: 8	Re: physical parameter in bsim3v3 Reply #7 - Feb 24^th, 2006, 7:28am Geoffrey_Coram wrote on Feb 24^th, 2006, 6:21am: This web page http://www.eecs.berkeley.edu/IPRO/Software/Catalog/Description/bsim3v2.0.html says that an extraction guide for BSIM3 is available for $1. �You may find it for free if you spend enough time with Google. Thanks Geoffrey. I will try to get it.
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