Jo, Pil Sung Sung, Jinwoo Park, Cheolmin Kim, Eunhye Ryu, Dit Yeol Pyo, Seungmoon Kim, Ho-Cheol Hong, Jae Min 2024-01-20T23:31:24Z 2024-01-20T23:31:24Z 2021-09-03 2008-04-25 1616-301X https://pubs.kist.re.kr/handle/201004/133545 We investigate the effect of surface topology of a block copolymer/neutral surface/SiO2 trilayered gate insulator on the properties of pentacene organic thin film transistor (OTFT) by the controlled etching of self assembled poly(styrene-b-methyl methacrylate) (PS-b-PMMA) block copolymer. The rms roughness of the uppermost block copolymer film directly in contact with pentacenes was systematically controlled from 0.27 nm to approximately 12.5 nm by the selective etching of cylindrical PMMA microdomains hexagonally packed and aligned perpendicular to SiO2 layer with 20 and 38 nm of diameter and periodicity, respectively. Both mobility and On/Off ratio were significantly reduced by more than 3 orders of magnitudes with the film roughness in OTFTs having 60nm thick pentacene active layer. The poor device performance observed with the etched thin film of block copolymer dielectric is attributed to a defective pentacene active layer and the mixed crystalline structure consisting of thin film and bulk phase arising from the massive nucleation of pentacene preferentially at the edge of each cylindrical etched hole. English WILEY-V C H VERLAG GMBH MOLECULAR-ORIENTATION DIELECTRIC ROUGHNESS MOBILITY PERFORMANCE ENHANCEMENT DEPENDENCE THICKNESS ENERGY Controlled topology of block copolymer gate insulators by selective etching of cylindrical microdomains in pentacene organic thin film transistors Article 10.1002/adfm.200701034 1 ADVANCED FUNCTIONAL MATERIALS, v.18, no.8, pp.1202 - 1211 ADVANCED FUNCTIONAL MATERIALS 18 8 1202 1211 scie scopus 000255695400006 2-s2.0-43249108629 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article MOLECULAR-ORIENTATION DIELECTRIC ROUGHNESS MOBILITY PERFORMANCE ENHANCEMENT DEPENDENCE THICKNESS ENERGY block copolymers dielectrics nanostructures organic thin-film transistors pentacene