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High crystalline quality thick β-Ga2O3drift layers are essential for multi-kV vertical power devices. Low-pressure chemical vapor deposition (LPCVD) is suitable for achieving high growth rates. This paper presents a systematic study of the Schottky barrier diodes fabricated on four different Si-doped homoepitaxial β-Ga2O3thin films grown on Sn-doped (010) and (001) β-Ga2O3substrates by LPCVD with a fast growth rate varying from 13 to 21 μm/h. A higher temperature growth results in the highest reported growth rate to date. Room temperature current density–voltage data for different Schottky diodes are presented, and diode characteristics, such as ideality factor, barrier height, specific on-resistance, and breakdown voltage are studied. Temperature dependence (25–250 °C) of the ideality factor, barrier height, and specific on-resistance is also analyzed from the J–V–T characteristics of the fabricated Schottky diodes.
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TCAD Simulation Models, Parameters, and Methodologies for β-Ga 2 O 3 Power Devices
β-Ga2O3is an emerging material and has the potential to revolutionize power electronics due to its ultra-wide-bandgap (UWBG) and lower native substrate cost compared to Silicon Carbide and Gallium Nitride. Sinceβ-Ga2O3technology is still not mature, experimental study ofβ-Ga2O3is difficult and expensive. Technology-Computer-Aided Design (TCAD) is thus a cost-effective way to study the potentials and limitations ofβ-Ga2O3devices. In this paper, TCAD parameters calibrated to experiments are presented. They are used to perform the simulations in heterojunction p-NiO/n-Ga2O3diode, Schottky diode, and normally-off Ga2O3vertical FinFET. Besides the current-voltage (I-V) simulations, breakdown, capacitance-voltage (C-V), and short-circuit ruggedness simulations with robust setups are discussed. TCAD Sentaurus is used in the simulations but the methodologies can be applied in other simulators easily. This paves the road to performing a holistic study ofβ-Ga2O3devices using TCAD.
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- Award ID(s):
- 2134374
- PAR ID:
- 10427227
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- ECS Journal of Solid State Science and Technology
- Volume:
- 12
- Issue:
- 5
- ISSN:
- 2162-8769
- Page Range / eLocation ID:
- Article No. 055002
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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