Processes for forming porous low k dielectric materials from low k dielectric films containing a porogen material include exposing the low k dielectric film to ultraviolet radiation. In one embodiment, the film is exposed to broadband ultraviolet radiation of less than 240 nm for a period of time and intensity effective to remove the porogen material. In other embodiments, the low k dielectric film is exposed to a first ultraviolet radiation pattern effective to increase a crosslinking density of the film matrix while maintaining a concentration of the porogen material substantially the same before and after exposure to the first ultraviolet radiation pattern. The low k dielectric film can be then be processed to form a metal interconnect structure therein and subsequently exposed to a second ultraviolet radiation pattern effective to remove the porogen material from the low k dielectrics film and form a porous low k dielectric film.