Dresden 2014 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

DS: Fachverband Dünne Schichten

DS 32: Focus session: Resistive Switching by Redox and Phase Change Phenomena III (Defect and material engineering in oxides)

DS 32.4: Vortrag

Mittwoch, 2. April 2014, 15:45–16:00, CHE 89

Oxygen engineered HfO_2−x as a CMOS compatible candidate for resistive switching — •Erwin Hildebrandt¹, S. U. Sharath¹, Jose Kurian¹, Mathis M. Mueller¹, Thomas Schroeder², Hans-Joachim Kleebe¹, and Lambert Alff¹ — ¹Institute of Material Science, Technische Universität Darmstadt, Alarich-Weiss-Straße 2, 64287 Darmstadt, Germany — ²IHP, Im Technologiepark 25, 15236 Frankfurt (Oder), Germany

Reactive molecular beam epitaxy has been applied to grow stoichiometric and oxygen deficient thin films of hafnium oxide. Films as thin as 10 nm were grown epitaxially on c-cut sapphire, proven by grazing incidence in-plane X-ray studies and high resolution transmission electron microscopy. As a function of oxygen vacancy concentration, the optical band gap varies by more than 1 eV and a sharp metal-insulator transition occurs. Hall-effect measurements indicate p-type conductivity with a mobility of 2 cm²/(Vs) for highly deficient thin films [1, 2]. The high oxygen vacancy concentrations - which are formed and stabilized in situ during the RMBE deposition process - lead to intrinsic resistivities as low as 300 µΩcm. We propose oxygen deficient hafnia thin films driven to the vicinity of the metal-insulator transition as a promising candidate for the functional layer of potentially forming-free and CMOS compatible resistive RAM devices.

[1] E. Hildebrandt, J. Kurian, M. M. Müller, T. Schroeder, H.-J. Kleebe, and L. Alff, Appl. Phys. Lett. 99, 112902 (2011)

[2] E. Hildebrandt, J. Kurian, and L. Alff, J. Appl. Phys. 112, 114112 (2012)