This invention has enabled a new, simple thin film nanoporous dielectric
fabrication method. In general, this invention uses glycerol, or another
low volatility compound, as a solvent. This new method allows thin film
aerogels/low density xerogels to be made without supercritical drying,
freeze drying, or a surface modification step before drying. Thus, this
invention allows production of nanoporous dielectrics at room temperature
and atmospheric pressure, without a separate surface modification step.
Although this new method allows fabrication of aerogels without
substantial pore collapse during drying, there may be some permanent
shrinkage during aging and/or drying. This invention allows controlled
porosity thin film nanoporous aerogels to be deposited, gelled, aged, and
dried without atmospheric controls. In another aspect, this invention
allows controlled porosity thin film nanoporous aerogels to be deposited,
gelled, rapidly aged at an elevated temperature, and dried with only
passive atmospheric controls, such as limiting the volume of the aging
chamber.