Chemical and structural properties of conducting nanofilaments in TiN/HfO2-based resistive switching structures

被引：69

作者：

Calka, P. ^{[1
]}

Martinez, E. ^{[1
]}

Delaye, V. ^{[1
]}

Lafond, D. ^{[1
]}

Audoit, G. ^{[1
]}

Mariolle, D. ^{[1
]}

Chevalier, N. ^{[1
]}

Grampeix, H. ^{[1
]}

Cagli, C. ^{[1
]}

Jousseaume, V. ^{[1
]}

Guedj, C. ^{[1
]}

机构：

[1] CEA, LETI, F-38054 Grenoble 9, France

来源：

NANOTECHNOLOGY | 2013年 / 24卷 / 08期

关键词：

YTTRIA-STABILIZED ZIRCONIA; ENERGY-LOSS SPECTROSCOPY; ELECTRONIC-STRUCTURE; DIELECTRICS; MEMORIES;

D O I：

10.1088/0957-4484/24/8/085706

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

Structural, chemical and electronic properties of electroforming in the TiN/HfO2 system are investigated at the nanometre scale. Reversible resistive switching is achieved by biasing the metal oxide using conductive atomic force microscopy. An original method is implemented to localize and investigate the conductive region by combining focused ion beam, scanning spreading resistance microscopy and scanning transmission electron microscopy. Results clearly show the presence of a conductive filament extending over 20 nm. Its size and shape is mainly tuned by the corresponding HfO2 crystalline grain. Oxygen vacancies together with localized states in the HfO2 band gap are highlighted by electron energy loss spectroscopy. Oxygen depletion is seen mainly in the central part of the conductive filament along grain boundaries. This is associated with partial amorphization, in particular at both electrode/oxide interfaces. Our results are a direct confirmation of the filamentary conduction mechanism, showing that oxygen content modulation at the nanometre scale plays a major role in resistive switching.

引用

页数：9

共 44 条

[21] Grain boundaries as preferential sites for resistive switching in the HfO2 resistive random access memory structures [J].