“…The responses of nerve cells to surface roughness have been studied on various substrates, such as porous silicon, [3] thin titanium nitride films, [4] carbon nanotubes, [5] topographically molded poly(dimethylsiloxane), [6,7] silicon pillar arrays, [8] gallium phosphide nanowires, [9] aligned nanofiber arrays, [10] and silicon nanowires. [11] Previous studies showed that nerve cells exhibit enhanced attachment and viability [3][4][5][6] as well as the axonal guidance effect [7-10, 12, 13] on rough surfaces, as opposed to topographically flat surfaces.…”