ε-Ga2O3: A Promising Candidate for High-Electron-Mobility Transistors
| Autor: | Qing Cai, Yi Tong, Guofeng Yang, Rong Zhang, Hai Lu, Dunjun Chen, Bin Liu, Hui Guo, Jin Wang, Cheng-Zhang Zhu, Junjun Xue, Youdou Zheng |
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| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Physics Condensed matter physics Band gap Transistor Doping Wide-bandgap semiconductor Gallium nitride 01 natural sciences Electronic Optical and Magnetic Materials law.invention chemistry.chemical_compound chemistry law 0103 physical sciences Electrical and Electronic Engineering High electron Fermi gas Saturation (magnetic) |
| Zdroj: | IEEE Electron Device Letters. :1-1 |
| ISSN: | 1558-0563 0741-3106 |
| Popis: | We predict spontaneous polarization of $\varepsilon $ -Ga2O3 can achieve a high density of 1014 cm−2 two-dimensional electron gas (2DEG) at the interface of $\varepsilon $ -Ga2O3 and ${m}$ -AlN ( ${m}$ -GaN) without doping. Based on the accurately calculated bandgap alignment of $\varepsilon $ -Ga2O3, AlN and GaN, we find that the critical thickness of the $\varepsilon $ -Ga2O3 to form a mobile 2DEG at the interface on ${m}$ -AlN and ${m}$ -GaN substrates is around 1.8 nm, which is much thinner than AlGaN due to its large potential shift. The depletion mode high-electron-mobility transistors (HEMTs) based on $\varepsilon $ -Ga2O3 are also investigated. The results show that the saturation currents of $\varepsilon $ -Ga2O3 HEMTs devices are much larger than that of typical AlGaN HEMTs. For the emerging problem of large leakage current from $\varepsilon $ -Ga2O3 HEMTs device, we present a novel method that can significantly suppress the off-state leakage current of the device by growing an ultrathin AlGaN layer on the top surface of $\varepsilon $ -Ga2O3. Therefore, our results can provide a theoretical basis for the potential applications of $\varepsilon $ -Ga2O3 in fabricating HEMTs for high-power and high-frequency applications. |
| Databáze: | OpenAIRE |
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