This invention provides a concept of using porous materials on ceramic substrate planarization. This planarized substrate consists of a ceramic substrate, a buffer layer, and a nanostructure layer. The ceramic substrate provides structural strength and surface-mount capability. The buffer layer provides the adhesion between the substrate and the nanostructure layer. The nanostructure layer provides the required surface smoothness of the ceramic substrates for performing thin-film processing techniques and enhances adhesion for metallization and electronic materials.