Polymeric　semiconductors　spin-coated　onto　the　photoresist　grating　form　discontinuously　distributed　flocci,　which　do　not　fill　grating　grooves　with　nanoscale　widths.　Thus,　the　polymer　layer　neither　forms　a　continuous　gain　channel　nor　creates　a　waveguide　that　enhances　the　distributed　feedback　(DFB)　mechanism　provided　by　the　grating　structures.　This　is　verified　by　the　microscopic　and　spectroscopic　investigations　on　the　topographic　surface　of　the　polymer-covered　grating　as　it　is　etched　layer　by　layer　using　oxygen　plasma.　This　gives　more　insights　into　the　mechanisms　involved　in　optically　pumped　polymer　lasers　and　provides　new　guidance　for　constructing　DFB　lasers.