Methods of preparing a low-k dielectric material on a substrate are provided. The methods involve using plasma techniques to remove porogen from a precursor layer comprising porogen and a dielectric matrix and to protect the dielectric matrix with a silanol capping agent, resulting in a low-k dielectric matrix. Porogen removal and silanol capping can occur concurrently or sequentially. If performed sequentially, silanol capping is performed without first exposing the dielectric matrix to moisture or ambient conditions.