A　hydrothermal　fabrication　of　ZnO　nanorod-based　grating　patterns　on　Si　substrates　is　reported.　The　arrays　of　optical　fiber　cores　were　manually　assembled　as　templates　with　nominal　pitches　of　250　gm　and　375　gm.　The　profiles　of　the　templates　and　the　grating　patterns　were　extracted　and　quantitatively　characterized　based　on　micrographs　of　scanning　electron　microscopy　(SEM)　and　Image　Processing　Toolbox　of　MATLAB.　The　errors　of　the　actual　pitches　and　the　parallelism　demonstrate　that　the　process　capability　of　manually　assembling　the　optical　fiber　cores　can　meet　the　quality　requirement　of　the　templates.　The　critical　dimensions　(CDs)　show　that　the　size　of　the　trough　formed　by　the　template　and　the　Si　substrate　determines　the　location　of　the　grating　pattern.　The　characteristic　parameters,　including　line　edge　roughness　(LER),　line　width　roughness　(LWR),　skewness　(Sk),　kurtosis　(Ku),　and　correlation　length　(zeta),　exhibit　that　the　three-phase　contact　lines　among　the　trapped　air　bubble,　ZnO　seed　solution,　and　Si　substrate　(or　the　optical　fiber　core)　decide　the　form　of　the　grating　pattern.　The　research　found　that　larger　nominal　pitch　of　the　template　resulted　in　larger　size　of　the　trough　which　further　led　to　less　CD,　and　higher　hydrophilicity　of　the　Si　surfaces　resulted　in　smoother　profiles　whilst　lower　hydrophilicity　of　the　optical　fiber　core　surfaces　led　to　rougher　ones.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.