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arXiv · 2408.11342

Dielectric Reliability and Interface Trap Characterization in MOCVD grown In-situ Al$_2$O$_3$ on $\beta$-Ga$_2$O$_3$

Saurav Roy·Arkka Bhattacharyya·Carl Peterson·Sriram Krishnamoorthy
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Abstract

In this article, we investigate the in-situ growth of Al$_2$O$_3$ on $\beta$-Ga$_2$O$_3$ using metal-organic chemical vapor deposition (MOCVD) at a high temperature of 800{\deg}C. The Al$_2$O$_3$ is grown within the same reactor as the $\beta$-Ga$_2$O$_3$, employing trimethylaluminum (TMAl) and O$_2$ as precursors without breaking the vacuum. We characterize the shallow and deep-level traps through stressed capacitance-voltage (C-V) and photo-assisted C-V methods. The high-temperature deposited dielectric demonstrates an impressive breakdown field of approximately 10 MV/cm. Furthermore, we evaluate the reliability and lifetime of the dielectrics using time-dependent dielectric breakdown (TDDB) measurements. By modifying the dielectric deposition process to include a high-temperature (800{\deg}C) thin interfacial layer and a low-temperature (600{\deg}C) bulk layer, we report a 10-year lifetime under a stress field of 3.5 MV/cm along a breakdown field of 7.8 MV/cm.

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Saurav Roy, Arkka Bhattacharyya, Carl Peterson, Sriram Krishnamoorthy. 2024-08-21. Dielectric Reliability and Interface Trap Characterization in MOCVD grown In-situ Al$_2$O$_3$ on $\beta$-Ga$_2$O$_3$. https://arxiv.org/abs/2408.11342

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