A method for electroplating a nonmetallic grating including providing a nonmetallic grating; performing an atomic layer deposition (ALD) reaction to form a seed layer on the nonmetallic grating; and electroplating a metallic layer on the seed layer such that the metallic layer uniformly and conformally coats the nonmetallic grating. An apparatus including a silicon substrate having gratings with an aspect-ratio of at least 20:1; a atomic layer deposition (ALD) seed layer formed on the gratings; and an electroplated metallic layer formed on the seed layer, wherein the electroplated metallic layer uniformly and conformally coats the gratings.