ZrO2 Based Multilayered Stacks with Al2O3, Y2O3 or La2O3 Interlayers for SiC Power Devices

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Sandra Krause - , Professur für Nanoelektronik (Autor:in)
  • Aleksey Mikhaylov - , Infineon Technologies AG (Autor:in)
  • Uwe Schroeder - , NaMLab - Nanoelectronic materials laboratory gGmbH (Autor:in)
  • Thomas Mikolajick - , Professur für Nanoelektronik, NaMLab - Nanoelectronic materials laboratory gGmbH (Autor:in)
  • Andre Wachowiak - , NaMLab - Nanoelectronic materials laboratory gGmbH (Autor:in)

Abstract

ZrO2 is a promising high-k dielectric for SiC power devices due to its favorable bandgap alignment with SiC. However, it exhibits low breakdown fields and excessively high leakage currents for thicker layers. This paper presents an approach to suppress this leakage current by integrating thin interlayers of Al2O3, Y2O3, or La2O3 into the ZrO2 film. These interlayers significantly reduce the charge carrier transport through ZrO2 films and, thereby, the leakage current of the stack. Among the investigated interlayers, Al2O3 shows the most pronounced effect, reducing the leakage of ZrO2-based thick films by 2 orders of magnitude and achieving a breakdown field of 7.4 MV/cm. This is comparable to the value measured for pure Al2O3 (7.7 MV/cm). These improvements can be attributed to the amorphous nature of the laminated oxide as the crystallization temperature could be increased from 350 °C for pure ZrO2 up to 750 °C for the nanolaminate. Notably, the dielectric constant of this optimized stack is 13, which is twice as high as that of pure Al2O3. No additional charge trapping due to the interlayers was detected by Capacitance-Voltage hysteresis measurements. Furthermore, by additional optimization of the stack’s deposition conditions, the charge trapping was reduced by 50% compared to pure ZrO2 films.

Details

OriginalspracheEnglisch
Seiten (von - bis)28789-28798
Seitenumfang10
FachzeitschriftACS Applied Materials and Interfaces
Jahrgang17
Ausgabenummer19
PublikationsstatusVeröffentlicht - 14 Mai 2025
Peer-Review-StatusJa

Externe IDs

PubMed 40315370
ORCID /0000-0003-3814-0378/work/185316025

Schlagworte

ASJC Scopus Sachgebiete

Schlagwörter

  • dielectrics, high-k, multilayer, nanolaminates, silicon carbide