no substrate in MOS layout "Gen form source",how t

[Depp]

no substrate in MOS' layout "Gen form source",how to LVS???

there is no substrate in the layout of MOS. but in schematic, the symbol of MOS has the substrate terminal.
then how could i complete the LVS ???

thank you !!!

 

[protonixs]

Re: no substrate in MOS layout "Gen form source",h

no substrate in MOS' layout "Gen form source",how to LVS???

there is no substrate in the layout of MOS. but in schematic, the symbol of MOS has the substrate terminal.
then how could i complete the LVS ???

thank you !!!

hi depp!
what do u mean no substrate in layout?
as far as i know, all region outside N-well in a twin well process is a pwell/psubstrate...

 

[Depp]

Re: no substrate in MOS layout "Gen form source",h

no substrate in MOS' layout "Gen form source",how to LVS???

there is no substrate in the layout of MOS. but in schematic, the symbol of MOS has the substrate terminal.
then how could i complete the LVS ???

thank you !!!

hi depp!
what do u mean no substrate in layout?
as far as i know, all region outside N-well in a twin well process is a pwell/psubstrate...

thank you for your reply,protonixs.
here is the snapshot of what said.

 

[protonixs]

Re: no substrate in MOS layout "Gen form source",h

put N well outside the p-type transistor...
the well outside the Nwell will be the p-substrate...
and dont forget to tie the bias of nwell and psub to VDD and VSS/gnd, respectively.
if u still have some doubts, dont hesitate to ask again.
good luck..
regards,
protonixs

 

[Depp]

Re: no substrate in MOS layout "Gen form source",h

put N well outside the p-type transistor...
the well outside the Nwell will be the p-substrate...
and dont forget to tie the bias of nwell and psub to VDD and VSS/gnd, respectively.
if u still have some doubts, dont hesitate to ask again.
good luck..
regards,
protonixs

thank you protonixs.

now, the point is, as the snapshot shows, there is no p-substrate in the layout which "Gen form source".

 

[protonixs]

Re: no substrate in MOS layout "Gen form source",h

that is right.. there is no psub layer. you dont have to draw pwell/psub because the well outside N wells will automatically be psub/pwell. got my point?

 

[safwatonline]

u need to put substrate contacts as close to the NMOS (follow ur latch-up rule) also u need to add NWell Contatcs to the PMOS(also follow ur latch up rules)

for inserting contacts press "O"

 

[Depp]

thank you, protonixs and safwatonline. thank you so much!!!
the hotkey "O" is so hot....haha...

Added after 33 minutes:

with the help of "O",now i can add the contacts manually .
but could these Contacts be generated automatically, just like the MOS ?

thank you .

 

[safwatonline]

this is dependent on ur pcells, some pdk's allow adding contacts automatically

 

[protonixs]

Re: no substrate in MOS layout "Gen form source",h

yeah it is dependent to your pdk...
sometimes this option is not enabled because guardring sharing of transistors is anticipated....

 

[Depp]

Re: no substrate in MOS layout "Gen form source",h

thank you , safwatonline and protonixs .
i find an item of "Insert Substrate Contacts" in the setup of "Auto Placer",but when i made it enable, there is an error saying:
Substrate contact type information incorrect or incomplete.
the attachment is the snapshot of error.
where can i find the substrate contact type information ???
thank you.

 

[protonixs]

Re: no substrate in MOS layout "Gen form source",h

thank you , safwatonline and protonixs .
i find an item of "Insert Substrate Contacts" in the setup of "Auto Placer",but when i made it enable, there is an error saying:
Substrate contact type information incorrect or incomplete.
the attachment is the snapshot of error.
where can i find the substrate contact type information ???
thank you.

hi depp,
i cant see any attachement in your post...
did you miss something?
regards

 

[Depp]

Re: no substrate in MOS layout "Gen form source",h

sorry, i upload the snapshot again.
thank you.

 

[protonixs]

Re: no substrate in MOS layout "Gen form source",h

i dont also understand the error.
did you put the right bias? it must p+ active connected to ground.
please show your layout.

 

[Depp]

Re: no substrate in MOS layout "Gen form source",h

if i choose the item of " Insert Substrate Contacts" when i start the auto-placer in layout XL,the error will turn up.
as it is shown in the attachment.

 

[Beerkaah]

Hi,
Can You just simply adding a PTAP ?
I mean like a via or contact...

Its just an idea because as safwatonline wrote before its depending on your Design Kit.

 

[Depp]

thank you Beerkaah.
the auto-router won't route the contacts i add manually.

 

[protonixs]

Re: no substrate in MOS layout "Gen form source",h

hi Depp!
if you want to know the property of the psub bias, select it then press Q.
verify if you placed the correct type.

 

[Depp]

thank you protonixs.
maybe i should try to draw a guard ring for the whole circuit instead of substrate for each MOS.