title: Self-Positioned Nanosized Mask for Transparent and Flexible Ferroelectric Polymer Nanodiodes Array.
abstract: High density arrays of ferroelectric polymer nanodiodes have gained strong attention for next-generation transparent and flexible nonvolatile resistive memory. Here, we introduce a facile and innovative method to fabricate ferroelectric polymer nanodiode array on an ITO-coated poly(ethylene terephthalate) (PET) substrate by using block copolymer self-assembly and oxygen plasma etching. First, polystyrene-block-poly(2-vinylpyridine) copolymer (PS-b-P2VP) micelles were spin-coated on poly(vinylidene fluoride-ran-trifluoroethylene) copolymer (P(VDF-TrFE)) film/ITO-coated PET substrate. After the sample was immersed in a gold precursor (HAuCl4) containing solution, which strongly coordinates with nitrogen group in P2VP, oxygen plasma etching was performed. During the plasma etching, coordinated gold precursors became gold nanoparticles (GNPs), which successfully acted as self-positioned etching mask to fabricate a high density array of P(VDF-TrFE)) nanoislands with GNP at the top. Each nanoisland shows clearly individual diode property, as confirmed by current-voltage (I-V) curve. Furthermore, due to the transparent and flexible nature of P(VDF-TrFE)) nanoisland as well as the substrate, the P(VDF-TrFE) nanodiode array was highly tranparent, and the diode property was maintained even after a large number of bendings (for instance, 1000 times). The array could be used as the next-generation tranparent and flexible nonvolatile memory device.
authors.affiliation: National Creative Research Initiative Center for Smart Block Copolymer Self-Assembly, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, Gyungbuk 790-784, Republic of Korea.
authors.forename: Seung
authors.initials: S
authors.lastname: Hyun
authors.affiliation: School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU) , Suwon, Gyeonggi-do 440-746, Republic of Korea.
authors.forename: Owoong
authors.initials: O
authors.lastname: Kwon
authors.affiliation: National Creative Research Initiative Center for Smart Block Copolymer Self-Assembly, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, Gyungbuk 790-784, Republic of Korea.
authors.forename: Chungryong
authors.initials: C
authors.lastname: Choi
authors.affiliation: National Creative Research Initiative Center for Smart Block Copolymer Self-Assembly, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, Gyungbuk 790-784, Republic of Korea.
authors.forename: Kanniyambatti L
authors.initials: KL
authors.lastname: Vincent Joseph
authors.affiliation: School of Advanced Materials Science and Engineering, Sungkyunkwan University (SKKU) , Suwon, Gyeonggi-do 440-746, Republic of Korea.
authors.forename: Yunseok
authors.initials: Y
authors.lastname: Kim
authors.affiliation: National Creative Research Initiative Center for Smart Block Copolymer Self-Assembly, Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, Gyungbuk 790-784, Republic of Korea.
authors.forename: Jin Kon
authors.initials: JK
authors.lastname: Kim
keywords: block copolymer micelle; electrical properties (I−V curve); ferroelectric hysteresis loops; ferroelectric polymer nanodiodes array; self-positioned nanosized mask; transparent and flexible memory device