The disclosed technology generally relates to semiconductor fabrication, and more particularly to plasma etching of dielectric materials having pores. In one aspect, a method for etching a porous material in an environment includes contacting the porous material with an organic gas at a pressure and a temperature. The organic gas is such that at the pressure and the temperature, the organic gas remains in a gas state when outside of the porous material, while the organic gas condenses into an organic liquid upon contacting the porous material. Upon contacting the porous material, the organic gas thereby fills the pores of the porous material with the organic liquid. Subsequent to contacting the porous material, the method additionally includes plasma etch-treating of the porous material having filled pores, thereby evaporating a fraction of the organic liquid filling the pores of the porous material.