I am getting the error as Fatal error: Rules must contain capacitance order statement in caliber while running pex as shown above
Usually the capacitance rules are provided in a separate rule file, called something like rules.C. (I hear some places combine them with rules.R, the resistance rules.)
To see what is in the rules your runset loaded, in Calibre Interactive Rules pane, click the View button. You may see a very sparse file (a lot of foundries like to keep things obscure by including by reference, so details don't show up in the transcript) but there should be either an include statement for rules.C or if you are in luck, all the SVRF and one of them will be CAPACITANCE ORDER.
If you don't see the capacitance rules, is there a set in your PDK? Perhaps you can include them. I mainly work on the command line, but Calibre Interactive should have a way to add to a set of rules.
If you are trying to custom define your own parasitics... not recommended for any processes 2003 or newer. It used to be doable, but below about 95 nm the interactions got complicated. Sheet resistance and grouped ground capacitance weren't enough. To see some of what is involved, you could take a look at the files shipped with the Calibre QuickStart example kit -- these likely won't be the same as for your process, but would demonstrate a full working setup. (The abstract says it uses a 45nm technology.) You can download the example kit from Support Center. Under Calibre Downloads, click the Related Downloads tab, and then the link "Calibre Utilities, Examples, Scripts, and Interface Software." The example kits are the last group of utilities.
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