Porous ceramic and hybrid ceramic films are useful as low dielectric constant interlayers in semiconductor interconnects. (Hybrid ceramic films are defined as films that contain organic and ceramic molecular components in the structure, as, for example, organosilicates). This invention describes the usefulness of humidity treatments (using specific temperature/humidity treatments as illustrative examples) in increasing mechanical integrity of porous dielectric films with minimal detrimental effect on film porosity or dielectric constant and with no adverse impact on film quality. The efficacy of such treatments is illustrated using surfactant-templated mesoporous silicate films as an example. This invention also describes a specific family of additives to be used with highly pure alkali-metal-free ceramic and hybrid precursors for such dielectric films that will enable better control of the film porosity and quality and lower dielectric constants with the required mechanical integrity. The efficacy of such additives is illustrated using surfactant-templated mesoporous silicate films as a model example. The invention should be broadly applicable to any cross-linked ceramic or hybrid ceramic films (including silicate and organosilicate films, and especially highly porous forms of the films for low-dielectric constant applications). The invention has been found to be particularly effective with surfactant-templated silicate films with nanometer-scale porosity. The invention in either embodiment should also be applicable to evaporation-induced formation of other cross-linked shapes such as fibers and powders.