The Current work discusses a novel process developed to fabricate free standing perforated membrane structures in polymers down to sub Micron pore diameter sizes. All parallel patterning processes which combine imprinting technology with micromachining techniques were used. High Aspect Ration Si molds fabricated using DRIE etching and treated with an in house developed anti adhesive coating was used to imprint on SU8 and PMMA Resists. A double layered imprinting technique using a Lift Off Resist as sacrificial layer was developed coupled with thermal imprinting and UV curing to achieve perforated membrane structures having higher mechanical stability than traditional NIL imprint resists like PMMA.