**5. Conclusions**

We here provided an overview of the typical oxide materials used to produce memristive devices and of their switching behavior. With specific reference to anodic oxides, their potential as switching components has been demonstrated, and the possibility to have an easy control over their thickness and composition with excellent repeatability is particularly appealing for the specific application envisioned. Yet, some open issues can be identified in this frame, namely, the downscaling of oxide area, and related problems of technological transfer at the sub-micrometric scale, and the verification of compatibility of such electrochemical wet process with CMOS fabrication.

[4] Waser R, Dittmann R, Staikov G, Szot K. Redox-based resistive switching memories - Nanoionic mechanisms, prospects, and challenges. Advanced Materials. 2009;**21**:2632-2663

Memristive Anodic Oxides: Production, Properties and Applications in Neuromorphic Computing

[5] Wong HSP, Lee HY, Yu S, Chen YS, Wu Y, Chen PS, et al. Metal-oxide RRAM. Proceedings

[6] Sahoo S, Prabaharan SRS. Nano-ionic solid state resistive memories (re-RAM): A review.

[7] Ielmini D. Resistive switching memories based on metal oxides: Mechanisms, reliability

[9] Chen X, Wang H, Sun G, Ma X, Gao J, Wu W. Resistive switching characteristic of electrolyte-oxide-semiconductor structures. Journal of Semiconductors. 2017;**38**:084003

for neuromorphic applications. In: 2016 IEEE International Symposium on Circuits and

[11] Lee M-J, Lee CB, Lee D, Lee SR, Chang M, Hur JH, et al. A fast, high-endurance and

[12] Diamanti MV, Garbagnoli P, Del Curto B, Pedeferri MP. On the growth of thin anodic oxides showing interference colors on valve metals. Current Nanoscience. 2015;**11**:307-316

[13] Diamanti MV, Ormellese M, Pedeferri M. Application-wise nanostructuring of anodic films on titanium: A review. Journal of Experimental Nanoscience. 2015;**10**:1285-1308 [14] Vanhumbeeck J-F, Proost J. Current understanding of Ti anodisation: Functional, morphological, chemical and mechanical aspects. Corrosion Reviews. 2009;**27**:117-204 [15] Lohrengel MM. Thin anodic oxide layers on aluminium and other valve metals: High

[16] Diamanti MV, Pedeferri MP. Effect of anodic oxidation parameters on the titanium

[17] Diamanti MV, Pozzi P, Randone F, Del Curto B, Pedeferri M. Robust anodic colouring of titanium: Effect of electrolyte and colour durability. Materials and Design.

[18] Sul Y-T, Johansson CB, Jeong Y, Albrektsson T. The electrochemical oxide growth behaviour on titanium in acid and alkaline electrolytes. Medical Engineering & Physics.

[19] Delplancke J-L, Degrez M, Fontana A, Winand R. Self-colour anodizing of titanium.

[20] Diamanti MV, Spreafico FC, Pedeferri MP. Production of anodic TiO<sup>2</sup>

their characterization. Physics Procedia. 2013;**40**:30-37

field regime. Materials Science & Engineering R: Reports. 1993;**11**:243-294

oxides formation. Corrosion Science. 2007;**49**:939-948

2016;**90**:1085-1091

2001;**23**:329-346

Surface Technology. 1982;**16**:153-162

based conductive bridging

http://dx.doi.org/10.5772/intechopen.79292

57

O5−*<sup>x</sup>*

/TaO2−*<sup>x</sup>*


bilayer struc-

Nanofilms and

Journal of Nanoscience and Nanotechnology. 2017;**17**:72-86

[8] Chen W, Tappertzhofen S, Barnaby HJ, Kozicki MN. SiO<sup>2</sup>

and scaling. Semiconductor Science and Technology. 2016;**31**:063002

random access memory. Journal of Electroceramics. 2017;**39**:109-131

[10] Covi E, Brivio S, Serb A, Prodromakis T, Fanciulli M, Spiga S. HfO<sup>2</sup>

scalable non-volatile memory device made from asymmetric Ta<sup>2</sup>

of the IEEE. 2012;**100**:1951-1970

Systems (ISCAS). 2016. pp. 393-396

tures. Nature Materials. 2011;**10**:625-630
