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.
|Number of pages||7|
|Journal||ACS applied electronic materials|
|Publication status||Published - 27 Dec 2022|
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ASJC Scopus subject areas
- back-end-of-line, ferroelectric, hafnium zirconium oxide, process pressure, sputtering, Ferroelectric, Hafnium zirconium oxide, Process pressure, Back-end-of-line, Sputtering