title: Reliable control of filament formation in resistive memories by self-assembled nanoinsulators derived from a block copolymer.
abstract: Resistive random access memory (ReRAM) is a promising candidate for future nonvolatile memories. Resistive switching in a metal-insulator-metal structure is generally assumed to be caused by the formation/rupture of nanoscale conductive filaments (CFs) under an applied electric field. The critical issue of ReRAM for practical memory applications, however, is insufficient repeatability of the operating voltage and resistance ratio. Here, we present an innovative approach to reliably and reproducibly control the CF growth in unipolar NiO resistive memory by exploiting uniform formation of insulating SiOx nanostructures from the self-assembly of a Si-containing block copolymer. In this way, the standard deviation (SD) of set and reset voltages was markedly reduced by 76.9% and 59.4%, respectively. The SD of high resistance state also decreased significantly, from 6.3 × 10(7) Ω to 5.4 × 10(4) Ω. Moreover, we report direct observations of localized metallic Ni CF formation and their controllable growth using electron microscopy and discuss electrothermal simulation results based on the finite element method supporting our analysis results.
authors.affiliation: Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Byoung Kuk
authors.initials: BK
authors.lastname: You
authors.forename: Woon Ik
authors.initials: WI
authors.lastname: Park
authors.forename: Jong Min
authors.initials: JM
authors.lastname: Kim
authors.forename: Kwi-Il
authors.initials: KI
authors.lastname: Park
authors.forename: Hyeon Kook
authors.initials: HK
authors.lastname: Seo
authors.forename: Jeong Yong
authors.initials: JY
authors.lastname: Lee
authors.forename: Yeon Sik
authors.initials: YS
authors.lastname: Jung
authors.forename: Keon Jae
authors.initials: KJ
authors.lastname: Lee
keywords: block copolymers; conductive filament; resistive memory; self-assembly