Jo, Yongcheol Jung, Kyooho Kim, Jongmin Woo, Hyeonseok Han, Jaeseok Kim, Hyungsang Hong, Jinpyo Lee, Jeon-Kook Im, Hyunsik 2024-01-20T08:04:01Z 2024-01-20T08:04:01Z 2021-09-05 2014-12-08 2045-2322 https://pubs.kist.re.kr/handle/201004/126001 This work reports on a mechanism for irreversible resistive switching (RS) transformation from bipolar to unipolar RS behavior in SrRuO3 (SRO)/Cr-doped SrZrO3 (SZO:Cr)/Pt capacitor structures prepared on a Ti/SiO2/Si substrate. Counter-clockwise bipolar RS memory current-voltage (I-V) characteristics are observed within the RS voltage window of -2.5 to +1.9 V, with good endurance and retention properties. As the bias voltage increases further beyond 4 V under a forward bias, a forming process occurs resulting in irreversible RS mode transformation from bipolar to unipolar mode. This switching mode transformation is a direct consequence of thermally activated Ti out-diffusion from a Ti adhesion layer. Transition metal Ti effectively out-diffuses through the loose Pt electrode layer at high substrate temperatures, leading to the unintended formation of a thin titanium oxide (TiOx where x < 2) layer between the Pt electrode and the SZO:Cr layer as well as additional Ti atoms in the SZO:Cr layer. Cross-sectional scanning electron microscopy, transmission electron microscopy and Auger electron spectroscopy depth-profile measurements provided apparent evidence of the Ti out-diffusion phenomenon. We propose that the out-diffusion-induced additional Ti atoms in the SZO:Cr layer contributes to the creation of the metallic filamentary channels. English NATURE PUBLISHING GROUP THIN-FILMS OXIDE-FILMS MEMORY ELECTRODES EVOLUTION Resistance switching mode transformation in SrRuO3/Cr-doped SrZrO3/Pt frameworks via a thermally activated Ti out-diffusion process Article 10.1038/srep07354 1 SCIENTIFIC REPORTS, v.4 SCIENTIFIC REPORTS 4 scie scopus 000346273700002 2-s2.0-84923233657 Multidisciplinary Sciences Science & Technology - Other Topics Article THIN-FILMS OXIDE-FILMS MEMORY ELECTRODES EVOLUTION resistance switching SrRuO3 Cr doped SrZrO3 Ti out-diffusion