TY - JOUR

T1 - Oxygen vacancy injection-induced resistive switching in combined mobile and static gradient doped tin oxide nanorods

AU - Herzog, Thomas

AU - Weitzel, Naomi

AU - Polarz, Sebastian

N1 - Funding Information: We gratefully acknowledge technical/instrumental support from the German Research Foundation (DFG) via SFB1214 Project Z1 Particle Analysis Center and the Nanolab of the University of Konstanz.

PY - 2020/9/21

Y1 - 2020/9/21

N2 - Resistive switching devices offer a great potential for advanced computing and data storage, including neuromorphic networks and random-access memory. State-of-the-art memristors are mostly realized by a three-layer structure, which is comprised of an active metal oxide layer sandwiched between two metal electrodes. Thus, there is always an interface involving two materials differing strongly in crystallographic and electronic properties. In this study, we present a resistive switching nanorod device based on a metal oxide sandwiched between two transparent conductive oxide electrodes. Thus, the system is characterized by a different, smooth interface offering new possibilities for increased energy efficiency and transparent electronics. Antimony-doped tin oxide (ATO) is used as an electrode material. The heavily doped ATO nanorods, exhibiting a good conductivity, are produced by a templated electrochemical deposition approach of alloy particles with subsequent thermal oxidation. The process enables precise control of the doping level within the nanorods and the formation of a doping level gradient. Electrical characterization reveals that a stronger gradient between heavily doped and undoped tin oxide within the nanorods results in a more rectifying character of the junction. Three-domain nanorods consisting of an undoped tin oxide segment in between two ATO segments are utilized to introduce memristive properties into the nanorod device. The resistive switching of these nanorods can be attributed to an oxygen vacancy doping gradient introduced during thermal oxidation. These vacancies are mobile within the tin oxide host structure and their injection from the ATO segment into the undoped tin oxide segment results in altered conductivity of the device, when an external bias is applied.

AB - Resistive switching devices offer a great potential for advanced computing and data storage, including neuromorphic networks and random-access memory. State-of-the-art memristors are mostly realized by a three-layer structure, which is comprised of an active metal oxide layer sandwiched between two metal electrodes. Thus, there is always an interface involving two materials differing strongly in crystallographic and electronic properties. In this study, we present a resistive switching nanorod device based on a metal oxide sandwiched between two transparent conductive oxide electrodes. Thus, the system is characterized by a different, smooth interface offering new possibilities for increased energy efficiency and transparent electronics. Antimony-doped tin oxide (ATO) is used as an electrode material. The heavily doped ATO nanorods, exhibiting a good conductivity, are produced by a templated electrochemical deposition approach of alloy particles with subsequent thermal oxidation. The process enables precise control of the doping level within the nanorods and the formation of a doping level gradient. Electrical characterization reveals that a stronger gradient between heavily doped and undoped tin oxide within the nanorods results in a more rectifying character of the junction. Three-domain nanorods consisting of an undoped tin oxide segment in between two ATO segments are utilized to introduce memristive properties into the nanorod device. The resistive switching of these nanorods can be attributed to an oxygen vacancy doping gradient introduced during thermal oxidation. These vacancies are mobile within the tin oxide host structure and their injection from the ATO segment into the undoped tin oxide segment results in altered conductivity of the device, when an external bias is applied.

UR - http://www.scopus.com/inward/record.url?scp=85091264143&partnerID=8YFLogxK

U2 - 10.1039/d0nr03734f

DO - 10.1039/d0nr03734f

M3 - Article

C2 - 32869823

AN - SCOPUS:85091264143

VL - 12

SP - 18322

EP - 18332

JO - Nanoscale

JF - Nanoscale

SN - 2040-3364

IS - 35

ER -