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【Member Papers】Xidian University---Breakdown voltage over 10 kV β-Ga₂O₃ heterojunction FETs with RESURF structure
日期：2025-06-03阅读：21
Researchers from the Xidian University have published a dissertation titled "Breakdown voltage over 10 kV β-Ga2O3 heterojunction FETs with RESURF structure" in Science China Information Sciences.
Project Support
This work was supported by National Natural Science Foundation of China (Grant No. 62222407), Guangdong Provincial Natural Science Foundation (Grant No. 2023B1515040024), and National Key Research and Development Program of China (Grant No. 2021YFA0716400).
Background
β-Ga2O3 has sparked a new wave of enthusiasm in the power community because of high-voltage and high-efficiency application demands, which is attributed to its superior ultrawide bandgap of 4.9 eV, theoretical critical electric field strength (EC) of 8 MV/cm, and high Baliga’s figure-of-merit of up to 3000. Bolstered by the large-size and low-cost substrate growth technique via the melt growth method, the development of β-Ga2O3-based power devices has increased rapidly. Tremendous effort has excited the power community, which is attributed to the experimental EC of up to 5.5 MV/cm, breakdown voltage (BV) boosting up to 10 kV, power figure of merit (PFOM) pushing up to 900 MW/cm2, and the achievement of vertical UMOSFET.
Conclusion
In summary, we have demonstrated the RESURF technique in β-Ga2O3 transistors, which benefits the E flatness and BV tolerance. The carefully designed charge density can ensure that the P-NiOX and N-β-Ga2O3 sides are fully depleted simultaneously. The RESURF P-NiOX/N-β-Ga2O3 HJ-FETs with tNiO = 110 nm achieve a BV of more than 10 kV and a PFOM of 63 MW/cm2. These results show the considerable power potential of β-Ga2O3 in the high-power and high-voltage communities.
Figure 1. (a) Cross-sectional schematic of the representative P-NiOX/N-β-Ga2O3 HJ-FETs. (b) Cross-sectional SEM image of the representative P-NiOX/N-β-Ga2O3 HJ-FETs. (c) Schematic cross-sectional view of the simulated carrier concentration and the simulated three-terminal off-state electric field distribution in the β-Ga2O3 channel at a VDS of 3000 V for the RESURF β-Ga2O3 HJ-FETs with tNiO of 50, 150, and 110 nm. (d) Output and (e) log-scale transfer characteristics of the RESURF P-NiOX/N-β-Ga2O3 HJ-FETs with tNiO = 110 nm. (f) Three-terminal breakdown characteristics of our devices with the LGD = 74 µm. (g) Benchmark of the power performance of the recent advanced β-Ga2O3 transistors.
DOI：
doi.org/10.1007/s11432-024-4332-4
