Hi, How can I find the device parameter (ucox) in xschem?

xschem is schematic editor, it lets you create netlists but has no idea about what's underneath the transistor model. Beyond that, uCox is a very rough idea from the days of square law modeling. You won't find uCox in a BSIM model. You can estimate what it roughly may be for a given set of bias conditions by running an operating point analysis and doing your own calculation.