Sputtered Ferroelectric Hafnium-Zirconium Oxide with High Remanent Polarization after Back-End-of-Line Compatible Annealing

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Xuetao Wang - , NaMLab - Nanoelectronic materials laboratory gGmbH (Author)
  • Thomas Mikolajick - , Chair of Nanoelectronics, NaMLab - Nanoelectronic materials laboratory gGmbH (Author)
  • Matthias Grube - , NaMLab - Nanoelectronic materials laboratory gGmbH (Author)

Abstract

The back-end-of-line (BEOL) processing compatibility of sputtered ferroelectric hafnium zirconium oxide (HZO) thin films is demonstrated on sputtered TiN/HZO/TiN thin-film ferroelectric capacitors. This promises an easy integration of HfO2-based ferroelectrics for applications such as non-volatile memories. It is found that the sputtering pressure can significantly influence the film growth and morphology of HZO layers. At a sputtering pressure of 5 × 10-3mbar, deposited HZO films show high remanent polarization (Pr) after 400 °C annealing, indicating a high fraction of the polar orthorhombic crystal structure. Additionally, the ferroelectric properties of HZO films were improved by proper tuning of sputtering power. We are able to show that a BEOL-compatible thermal budget (at 400 °C for 1 h) is enough to provoke good ferroelectricity with the 2Prof up to 36 μC/cm2and an endurance of up to 107cycles in sputtered HZO films. With such modifications, the sputtered HZO films become comparable to atomic-layer deposited HZO films with a similar thermal budget.

Details

Original languageEnglish
Pages (from-to)6142-6148
Number of pages7
JournalACS applied electronic materials
Volume4
Issue number12
Publication statusPublished - 27 Dec 2022
Peer-reviewedYes

External IDs

unpaywall 10.1021/acsaelm.2c01259
WOS 000892856000001

Keywords

DFG Classification of Subject Areas according to Review Boards

Subject groups, research areas, subject areas according to Destatis

Keywords

  • back-end-of-line, ferroelectric, hafnium zirconium oxide, process pressure, sputtering, Ferroelectric, Hafnium zirconium oxide, Process pressure, Back-end-of-line, Sputtering