By Topic

Chemical state and atomic structure of Ge2Sb2Te5 system for nonvolatile phase-change random access memory

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $31
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

10 Author(s)
Jung, Min-Cherl ; Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang, 790-784, Republic of Korea ; Kim, Ki-hong ; Lee, Young-Mi ; Eom, Jae-Hyeon
more authors

Your organization might have access to this article on the publisher's site. To check, click on this link:http://dx.doi.org/+10.1063/1.2990766 

We present chemical state information on contamination-free Ge2Sb2Te5 thin film using high-resolution x-ray photoelectron spectroscopy (HRXPS) and the corresponding theoretical understanding of the chemical states, on both amorphous and metastable phases, illuminating the phase-change mechanism of the system. HRXPS data revealed that the Sb 4d shallow core level was split into two components having different binding energies and that the spin-orbit splitting feature of the Ge 3d level was enhanced as the system became metastable. Negligible change was observed in the Te 4d shallow core level, and in contrary to the previous report’s prediction less change in valance band spectra was observed. The results imply that Sb movement is also involved in the phase-change mechanism and that acquisition of shallow core-level spectra can be a useful measure for understanding phase-change mechanism. Hydrogenated SbTe6 octahedral-like cluster model was introduced to schematically interpret the generation of the two components in the Sb 4d level in metastable state, having an isotropic six-bonds configuration, and an anistropic six-bonds (three-short and three-elongated bonds) configuration. The amorphous state was modeled to have three-short bonds configuration. Finally, Stibnite-like building block model was used to show that the existence of the above two configurations for Sb atoms is feasible in the Ge2Sb2Te5 system.

Published in:

Journal of Applied Physics  (Volume:104 ,  Issue: 7 )