Laboratory based X-ray photoemission core-level spectromicroscopy of resistive oxide memories

Daniel M. Gottlob (1) , Eugénie Martinez (2) , Claire Mathieu (1) , Christophe Lubin (1) , Nicolas Chevalier (2) , Munique Kazar Mendes (2) , Christelle Charpin (2) , Eric Jalaguier (2) , Olivier Renault (2) , Nick Barrett (1)

1 LENSIS - Laboratoire d'Etude des NanoStructures et Imagerie de Surface
2 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information

HfO$_2$-based resistive oxide memories are studied by core-level spectromicroscopy using a laboratory-based X-ray photoelectron emission microscope (XPEEM). After forming, the top electrode is thinned to about 1 nm for the XPEEM analysis, making the buried electrode/HfO$_2$ interface accessible whilst preserving it from contamination. The results are obtained in the true photoemission channel mode from individual memory cells (5 × 5 μm) excited by low-flux laboratory X-rays, in contrast to most studies employing the X-ray absorption channel using potentially harmful bright synchrotron X-rays. Analysis of the local Hf 4f, O 1s and Ti 2p core level spectra yields valuable information on the chemistry of the forming process in a single device, and in particular the central role of oxygen vacancies thanks to the spectromicroscopic approach.

Keywords: Resistive switching; HfO 2; PEEM

Domains: Physics [physics]

Daniel M. Gottlob, Eugénie Martinez, Claire Mathieu, Christophe Lubin, Nicolas Chevalier, et al.. Laboratory based X-ray photoemission core-level spectromicroscopy of resistive oxide memories. Ultramicroscopy, 2017, 4, pp.1 - 5. ⟨10.1016/j.ultramic.2017.03.026⟩. ⟨cea-01591611⟩