New hardmask compositions comprising non-polymeric, metal-conlaining nanoparticles dispersed or dissolved in a solvent system and methods of using those compositions as hardmask lavcrs in microelectronic structures are provided. The compositions arc photosensitive and capable of being rendered developer soluble upon exposure to radiation. The inventive hardmask layer is patterned simultaneously with the photoresist layer and provides plasma etch resistance for subsequent pattern transfer.