Year: 2025
Type: article
Abstract: We demonstrate high-performance MOSFETs on β-Ga2O3 films grown by plasma-assisted molecular beam epitaxy (PA-MBE). The high crystalline quality of the β-Ga2O3 epilayer was confirmed by X-ray diffraction and atomic force microscopy. An optimized CF4-plasma treatment was employed to introduce fluorine (F) into the near-surface region, effectively suppressing donor-like states. The resulting devices exhibit an ultralow off-state current of 1 × 10−9 mA/mm and a stable on/off ratio of 105. A controllable positive threshold voltage shift up to +12.4 V was achieved by adjusting the plasma duration. X-ray photoelectron spectroscopy indicates that incorporated F atoms form F–Ga-related bonds and compensate oxygen-related donor defects. Sentaurus TCAD simulations reveal reduced near-surface charge and a widened depletion region, providing a physical explanation for the experimentally observed increase in breakdown voltage from 453 V to 859 V. These results clarify the role of fluorine in modulating surface defect states in PA-MBE β-Ga2O3 and demonstrate an effective route for threshold-voltage engineering and leakage suppression in Ga2O3 power devices.
Source: Nanomaterials
DOI: 10.3390/nano15241896
Authors: Lisheng Wang, Yifan Zhang, Junxing Dong, Jingzhuo Wang, Zenan Wang, Yuan Feng, Xianghu Wang, Si Shen, Hai Zhu
Language: English
Topic: Ga2O3 and related materials
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,896
OpenAlex ID: W4417435965