ZrO 2 Based Multilayered Stacks with Al 2 O 3 , Y 2 O 3 or La 2 O 3 Interlayers for SiC Power Devices
Year: 2025
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide ZrO 2 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 Al 2 O 3, Y 2 O 3, or La 2 O 3 into the ZrO 2 film. These interlayers significantly reduce the charge carrier transport through ZrO 2 films and, thereby, the leakage current of the stack. Among the investigated interlayers, Al 2 O 3 shows the most pronounced effect, reducing the leakage of ZrO 2 -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 Al 2 O 3 (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 ZrO 2 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 Al 2 O 3 . 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 ZrO 2 films.
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Award: G3214297770
OpenAlex ID: W4410020095