# A New Cell Topology for 4H-SiC Planar Power MOSFETs for High-Frequency Switching

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## Abstract

**:**

## 1. Introduction

## 2. Device Design and Fabrication

## 3. Experimental Results and Discussion

#### 3.1. Statistic Performance

#### 3.2. Dynamic Performance

## 4. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Abbreviations

SiC | Silicon Carbide |

MOSFET | Metal-Oxide-Semiconductor Field-Effect Transistor |

JFET | Junction Field-Effect Transistor |

JBSFET | Junction Barrier Schottky (JBS) diode-integrated MOSFET |

HF-FOM | High-Frequency Figure of Merit |

DPT | Double-Pulse Test |

## References

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**Figure 1.**(

**a**) Dodecagonal cell topology, (

**b**) Octagonal cell topology, (

**c**) A-A’ cross-sectional view of the 650 V SiC power MOSFET. (

**d**) Cross-sectional SEM image of the fabricated 650 V SiC power MOSFET with the Dod cell.

**Figure 2.**(

**a**) Transfer characteristics at ${\mathrm{V}}_{\mathrm{D}}$ = 100 mV (solid line: drain current vs. gate voltage; dash line: transconductance vs. gate voltage), (

**b**) blocking characteristics at ${\mathrm{V}}_{\mathrm{G}}$ = 0 V, and (

**c**) output characteristics at ${\mathrm{V}}_{\mathrm{G}}$ = 20 V, for the 650 V SiC power MOSFETs with Dod and Oct cells.

**Figure 4.**(

**a**) Turn-on and (

**b**) turn-off waveforms of the fabricated 650 V SiC power MOSFETs with the Dod and the Oct cells.

Cell Topology | Oct | Dod | |
---|---|---|---|

Design parameters | Cell pitch ($\mathsf{\mu}$m) | 8.4 | 8.4 |

Active area (mm${}^{2}$) | 0.643 | 0.634 | |

Channel density ($\mathsf{\mu}$m${}^{-1}$) | 0.113 | 0.181 | |

JFET density | 0.034 | 0.055 | |

Experimental results | ${\mathrm{V}}_{\mathrm{th}}$ (V) | 4.09 ± 0.09 * | 4.35 ± 0.10 |

BV (V) @ ${\mathrm{I}}_{\mathrm{D}}$ = 100 $\mathsf{\mu}$A | 756.3 ± 22.6 | 753.4 ± 23.6 | |

${\mathrm{R}}_{\mathrm{on},\mathrm{sp}}$ (m$\mathrm{\Omega}\phantom{\rule{0.166667em}{0ex}}\xb7\phantom{\rule{0.166667em}{0ex}}$cm${}^{2}$) @ ${\mathrm{V}}_{\mathrm{D}}$ = 1.5 V | 24.4 ± 7.52 | 10.9 ± 3.06 | |

${\mathrm{C}}_{\mathrm{gd}}$ (pF) @ ${\mathrm{V}}_{\mathrm{D}}$ = 400 V | 1.59 ± 0.01 | 1.63 ± 0.04 | |

HF-FOM (m$\mathrm{\Omega}\phantom{\rule{0.166667em}{0ex}}\xb7\phantom{\rule{0.166667em}{0ex}}$pF) (${\mathrm{R}}_{\mathrm{on}}\phantom{\rule{0.166667em}{0ex}}\xb7\phantom{\rule{0.166667em}{0ex}}{\mathrm{C}}_{\mathrm{gd}}$) | 6031 ± 1896 | 2817 ± 749 | |

dv/dt turn-on ($\mathrm{V}/\mathrm{ns}$) | 6.1 | 12.5 | |

Switching loss turn-on ($\mathsf{\mu}$J) | 29.4 | 20.1 | |

dv/dt turn-off ($\mathrm{V}/\mathrm{ns}$) | 8.4 | 10.7 | |

Switching loss turn-off ($\mathsf{\mu}$J) | 5.7 | 4.7 | |

Total switching loss ($\mathsf{\mu}$J) | 35.1 | 24.8 |

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## Share and Cite

**MDPI and ACS Style**

Zhu, S.; Liu, T.; Fan, J.; Salemi, A.; White, M.H.; Sheridan, D.; Agarwal, A.K.
A New Cell Topology for 4H-SiC Planar Power MOSFETs for High-Frequency Switching. *Materials* **2022**, *15*, 6690.
https://doi.org/10.3390/ma15196690

**AMA Style**

Zhu S, Liu T, Fan J, Salemi A, White MH, Sheridan D, Agarwal AK.
A New Cell Topology for 4H-SiC Planar Power MOSFETs for High-Frequency Switching. *Materials*. 2022; 15(19):6690.
https://doi.org/10.3390/ma15196690

**Chicago/Turabian Style**

Zhu, Shengnan, Tianshi Liu, Junchong Fan, Arash Salemi, Marvin H. White, David Sheridan, and Anant K. Agarwal.
2022. "A New Cell Topology for 4H-SiC Planar Power MOSFETs for High-Frequency Switching" *Materials* 15, no. 19: 6690.
https://doi.org/10.3390/ma15196690