this invention provides a process for making an insulation layer for use in microelectronic devices , whereby capacitive coupling and propagation delay in the microelectronic devices are reduced . this invention can include the formation of a stable solution of nanometer - scale particles consisting of an inorganic core 10 that is decorated with a known number of fullerene molecules 20 , and including a soluble component that can act to bind the particles together into an integral structure . this solution can be applied to a microelectronic substrate , and dried to form a continuous , porous layer . porous layers formed by the process of this invention possess a very low dielectric constant , and can be produced using equipment and techniques common and available to those skilled in the art of microelectronic fabrication .