Create solid thermal vias using Orcad

Hello,

I need to create a solid thermal via to be used under a powerpad package. The specification of the via is mentioned below:

1) The thermal vias should make their connection to the internal ground plane with a complete connection around the entire circumference of the plated through hole. Place a ring of exposed copper (0.05 mm wide) around the vias at the bottom copper plane.
2) Do not cover the vias with solder mask.
3) Do not use a thermal relief web or spoke connection.
4) The recommended via diameter is 0.3 mm or less.

Could someone help me in creating such a via using Orcad? Should the via be created while making the footprint or during the layout?

Thanks.

Ananya