A resist polymer that has nano-scale patterns located therein that are in the form of sub lithographic hollow pores (or openings) that are oriented in a direction that is substantially perpendicular with that of its major surfaces (top and bottom) is provided. Such a resist polymer having the nano-scale patterns is used as an etch mask transferring nano-scale patterns to an underlying substrate such as, for example, dielectric material. After the transferring of the nano-scale patterns into the substrate, nano-scale voids (or openings) having a width of less than 50 nm are created in the substrate. The presence of the nano-scale voids in a dielectric material lowers the dielectric constant, k, of the original dielectric material. In accordance with an aspect of the present invention, the inventive resist polymer comprises a copolymer that includes a first monomer unit (A) that contains a Si-containing component, and a second monomer unit (B) that contains an organic component, wherein said two monomer units (A and B) have different etch rates.