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Hi all I am getting this issue while simulating t...
# ieee-sscs-dc-23
a
Hi all I am getting this issue while simulating test_cap_mim_2f0fF. Other test like nmos_cap etc are working fine only mim_cap test is not working.
k
@Atif Khan Could you share the netlist please ?
a
I am simulating built in prototype test_mim_cap_2p0fF of gf 180
k
I ran it out of the box so please share your netlist
a
message has been deleted
k
ok so try to add something like this below line 10 of your netlist 
.lib /home/shahid/OSPDKs/gf180mcuC/libs.tech/ngspice/sm141064.ngspice cap_mim
a
I have added that still not working but i think there is issue in lib model I have changed that and it is working
Here it was 2f0fF instead of 2p0fF.
k
so verify if in the *.lib file there exist a section 
.lib cap_mim
.endl
I suppose that it exist because in the line 19202 yo have a statement .endl cap_mim
a
Yes the .lib of cap_mim was available but I think above mentioned issue was there if I am correct
k
and what about 
cap_mim_2f0fF
? does it exists in the file ?
ok, what I am seeing now is that we have different default testbenches, in my case yours even does not exists. But still your file defines 
cap_mim_2p0fF
so it should be consistent. What about the file names?
pleas run this in your libs.tech/ngspice directory 
cat sm141064.ngspice | grep 'cap_mim'
a
No symbol of 2p0fF exist but 2f0fF doesn't
Can you send me yours lib sim141064
k
sure
but my lib does not have the 
cap_mim_2p0fF
I have my GF180 pdk installed using volare form efabless and maybe there are some updates
a
In my lib I have by mistake or what it is written as subckt name cap_mim_2f0fF in one place all other places it is 2p0fF so I think it was mistake in lib
k
sounds reasonably
a
Same it exist in your file line 39186 have a look it is written 2f0fF
k
here is my netlist
a
Your symbol of cap name is 2f0fF mine 2p0fF that's why mine was not because in .lib we have info about 2f0fF but there is no info about 2p0fF. I guess In cadence we have things like 2p, 3p0fF etc but I haven't seen things like 2f0 etc
k
Copy code
cat sm141064.ngspice | grep 'cap_mim'
*      cap_mim_1f5fF       Subcircuit Model for 1.5fF/um2 MIM (*)-usable for Volt <=6V across capacitor
*      cap_mim_1f0fF       Subcircuit Model for 1.0fF/um2 MIM (*)-usable for Volt <=20V across capacitor 
*      cap_mim_2f0fF       Subcircuit Model for 2fF/um2 MIM      -usable for Volt <=6V across capacitor
.lib 'sm141064_mim.ngspice' cap_mim_new
.lib 'sm141064_mim.ngspice' cap_mim_new
.lib 'sm141064_mim.ngspice' cap_mim_new
.LIB cap_mim
.subckt cap_mim_1f5fF 1 2  c_length=l c_width=w dtemp=0 par=1
.ends cap_mim_1f5
.subckt cap_mim_1f0fF 1 2  c_length=l c_width=w dtemp=0 par=1
.ends cap_mim_1f0
.subckt cap_mim_2f0fF  1 2  c_length=l  c_width=w dtemp=0 par=1
.ends cap_mim_2f0
.ENDL cap_mim
.lib 'sm141064_mim.ngspice' cap_mim_new
this is form IIC-OSIC tools, mine from volare is identical so there is an issue with your PDK I think
this line in your xschem *.sch file is suspicious '.lib $::180MCU_MODELS/sm141064_2.ngspice cap_mim'
a
This is modified lib in which I have changed 2f0fF to 2p0fF and it started working
I have made copy of original and did changes in new lib that's why this is in my sch
k
maybe just for testing you could put your new model in the orginal file
👍 1
t
@Atif Khan: The "2f0" name is the correct one; it refers to the 2fF/um^2 MiM cap option in the GF process (the other possible options are 1fF/um^2 and 1.5fF/um^2; we use the 2fF/um^2 option on the ChipIgnite runs, so that is the one defined in gf180mcuD). Make sure that your PDK is up-to-date. FYI, the technology "gf180mcuC" was used for the 1st GF Google-sponsored open MPW run. However, on advice from GF, it should not be used again. Use "gf180mcuD" instead. It has a slightly thicker top metal layer. GF says that the thinner top metal layer has issues with delamination on the pads.
👍 2
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