+ Post New Thread
Results 1 to 8 of 8

31st October 2005, 10:36 #1
uncox
Hello everyone!
Can anyone tell me how to calculate µnCox by using table 2.1 of page 37 in "Design of Analog CMOS Integrated Circuits" which is written by Razavi ?

31st October 2005, 10:36

31st October 2005, 14:09 #2
 Join Date
 Aug 2005
 Location
 Shanghai
 Posts
 351
 Helped
 16 / 16
 Points
 3,237
 Level
 13
uncox silicon
as in your file ,
for nmos Un=U0=350
for pmos Up=100
Cox=εox/tox,
where εox is the dielectric constant of the silicon dioxide(approximately 3.45e5pf/um),tox is the thickness of the oxide.

1st June 2010, 15:04 #3
 Join Date
 Jun 2010
 Posts
 1
 Helped
 0 / 0
 Points
 451
 Level
 4
How to calculate unCox ?
εox where?

1st June 2010, 15:04

1st June 2010, 15:47 #4
 Join Date
 Sep 2008
 Location
 Germany
 Posts
 7,873
 Helped
 2579 / 2579
 Points
 50,294
 Level
 54
Re: How to calculate unCox ?
εox = ε0 * εr(SiO2) = 8.854e6 pF/µm * 3.9 = 34.5e6 pF/µm = 34.5 aF/µm

11th July 2011, 14:14 #5
 Join Date
 Jul 2011
 Posts
 3
 Helped
 0 / 0
 Points
 267
 Level
 3
Re: How to calculate unCox ?
whats UnCox in 90nm?

11th July 2011, 14:32 #6
 Join Date
 Sep 2008
 Location
 Germany
 Posts
 7,873
 Helped
 2579 / 2579
 Points
 50,294
 Level
 54
Re: How to calculate unCox ?
See e.g. this PTM model card.
BTW: Values given there in SI units.

11th July 2011, 16:01 #7
 Join Date
 Jul 2011
 Posts
 3
 Helped
 0 / 0
 Points
 267
 Level
 3
Re: How to calculate unCox ?
can you get me a value? , because i m can not find it in library.
 Post added at 16:01  Previous post was at 15:52 
can you get me a value? , because i m can not find it in library.

11th July 2011, 16:01

11th July 2011, 16:10 #8
 Join Date
 Mar 2008
 Location
 USA
 Posts
 5,586
 Helped
 1630 / 1630
 Points
 34,904
 Level
 45
Re: How to calculate unCox ?
u is a surface mobility and will vary with gate processing,
at least as much as bulk doping.
At very short channels velocity saturation is a real thing
and at high channel fields the u0 may not be what defines
the conduction.
So you may find u0 values that make the model fit, but
diverge from classical values.
+ Post New Thread
Please login