A thin-film device system includes a substrate and a plurality of pillars. The plurality of pillars project from a surface of the substrate. Each of the plurality of pillars have a perimeter that includes at least four protrusions that define at least four recessed regions between the at least four protrusions. Each of the at least four recessed regions of each of the plurality of pillars receives one protrusion from an adjacent one of the plurality of pillars. A thin-film device is fabricated over the plurality of pillars.