I'm using umc90mm library. These are the categories of capacitors and resistors present here-
Capacitors - MIMCAPS, MOMCAPS, NCAP, VARDIOP, VARMIS
Resistors - RM1 to RM9, RNHR1000, RNHR, RNND, RNNPO, RNPD, RNPPO, RSNWELL, RSPD, RSPPO
Which among these have close to ideal characteristics?
Why you want to use a tech capacitor and resistor next to ideal characteristics? There is no such thing. If you want something next to ideal, use and ideal one.