부산대학교 도서관

Development of high permittivity dielectrics is critical for the electrical field management in devices made with ultra-wide bandgap (UWBG) semiconductors such as $\beta$-Ga 2 O 3 . High permittivity dielectrics are typically deposited at high temperatures and their integration with low temperature atomic-layer deposition (ALD) processed dielectrics offers a significant challenge. In this article, we studied the quality of high permittivity dielectric $\text{Ba}_{\mathrm{x}}\text{Sr}_{1-\mathrm{x}}\text{TiO}_{3}$ deposited using pulsed laser deposition (PLD) on ALD-grown SiO 2 and investigated the electronic properties of this dielectric stack formed on (010) $\beta$-Ga 2 O 3 Sn-doped substrates. We varied the PLD deposition parameters (such as temperature and target composition) and identified conditions that can withstand an effective breakdown electric field ($E_{eff, BD}$; calculated in reference to SiO 2 ) of > 30 MV/cm within the dielectric stack while maintaining low leakage ≤ 10 −8 A/cm 2 at $E_{eff} < 5.8-7.6\ \text{MV}/\text{cm}$. Interface defect characterization in the devices exhibited a high defect density at the SiO 2 / $\beta$-Ga 2 O 3 interface.