Oxygen vacancy concentration as a function of cycling and polarization state in TiN/Hf0.5Zr0.5O2/TiN ferroelectric capacitors studied by x-ray photoemission electron microscopy

Research output: Contribution to journalResearch articleContributedpeer-review



We have studied the field cycling behavior of microscopic TiN/Hf0.5Zr0.5O2/TiN ferroelectric capacitors using synchrotron-based soft x-ray photoemission electron microscopy. The oxygen vacancy (V O) concentration near the top TiN/Hf0.5Zr0.5O2 interface is estimated from the reduction of Hf4+ to Hf3+ as measured in the Hf 4f core level spectra. The V O concentration increases with field cycling and redistributes under the effect of the internal field due to the polarization. Upward pointing polarization slightly depletes the concentration near the top interface, whereas downward polarization causes V O drift toward the top interface. The V O redistribution after wake-up is consistent with shifts in the I-V switching peak. The Schottky barrier height for electrons decreases systematically with cycling in polarization states, reflecting the overall increase in V O.


Original languageEnglish
Article number202902
JournalApplied physics letters
Issue number20
Publication statusPublished - 16 May 2022

External IDs

Scopus 85130687387
Mendeley ffcc75cd-1a1d-3a5c-a14b-093e7183dd0d
WOS 000799794100006
unpaywall 10.1063/5.0093125


DFG Classification of Subject Areas according to Review Boards

Library keywords