@article{424ac4745bc4493781f2f65fbdcac0bb,
title = "Effect of the AlGaO Spacer Layer on the Performance of β-Gallium Oxide Metal–Oxide Semiconductor Field Effect Transistors",
abstract = "This study utilizes a metalorganic chemical vapor deposition system to grow a β-Ga2O3 epitaxial layer on a sapphire substrate and fabricate lateral β-Ga2O3 metal-oxide-semiconductor field-effect transistors (MOSFETs). To enhance the performance of the β-Ga2O3 MOSFET, a (AlxGa1-x)2O3 spacer layer is introduced, with its aluminum (Al) composition modulated through energy band engineering. Three epitaxial samples are designed: a reference sample (without a spacer layer) and samples with (AlxGa1-x)2O3 layers containing different Al compositions, specifically (Al0.14Ga0.86)2O3 and (Al0.21Ga0.79)2O3. The influence of the Al composition in the (AlxGa1-x)2O3 layer on the two dimensional electron gas (2DEG) is investigated. The results show that a lower Al composition increases the carrier concentration in the 2DEG, boosting the saturation current (ID,sat) from 2.94 to 7.88 mA mm−1—a significant 168\% improvement in the (AlxGa1-x)2O3/β-Ga2O3 stacked epitaxy structure. For the high-Al-composition barrier layer ((Al0.21Ga0.79)2O3), the higher energy barrier slightly reduces the turn-on current but effectively increases the breakdown voltage, from 210 to 576 V—an improvement of 188\%. These improvements result from the higher energy barrier of the β-Ga2O3/(AlxGa1-x)2O3 interface, which reduced the leakage current density. By optimizing the Al composition in (AlxGa1-x)2O3, transistors suitable for either high performance or high breakdown voltage are successfully produced.",
keywords = "(AlGa)O, GaO, MOCVD, high breakdown voltage, two dimensional electron gas (2DEG)",
author = "Chung, \{Sheng Ti\} and Catherine Langpoklakpam and Yicong Dong and Hsiao, \{Yi Kai\} and Shaloo Rakheja and Kuo, \{Hao Chung\} and Wuu, \{Dong Sing\} and Kenneth J{\"a}rrendahl and Hsiao, \{Ching Lien\} and Edmund Dobro{\v c}ka and Milan {\v T}apajna and Filip Gucmann and Horng, \{Ray Hua\}",
note = "The authors also wish to express their sincere gratitude for the financial support from the Higher Education Sprout Project of the National Yang Ming Chiao Tung University and the Ministry of Education (MOE), Taiwan. The authors also acknowledge the Industrial Technology Research Institute and MAtek Corporation for funding and material measurement support. This work was supported by the National Science and Technology Council (Taiwan, R.O.C.) under Grant Nos. 113-2221-E-A49-052-MY3, 112-2622-E-A49-011, 112-2221-E-A49-069-MY3, 113- 2622-8-A49-012-SB, 110-2222-E-009-006-MY3, 111-2923-E-A49-003-MY3, and 112-2622-8-A49-013-SB and the Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Link{\"o}ping University (Faculty Grant SFO-Mat-LiU No. 2009-00971) for financial support. This work was also supported by the Ministry of Education (Taiwan) under 2024 MOE UI-UAAT. Cooperation Project. F.G. and M.{\v T}. acknowledge funding from the Slovak Research and Development Agency (APVV-20-0220), and the Slovak grant agency VEGA (2/0156/25). The authors also wish to express their sincere gratitude for the financial support from the Higher Education Sprout Project of the National Yang Ming Chiao Tung University and the Ministry of Education (MOE), Taiwan. The authors also acknowledge the Industrial Technology Research Institute and MAtek Corporation for funding and material measurement support. This work was supported by the National Science and Technology Council (Taiwan, R.O.C.) under Grant Nos. 113‐2221‐E‐A49‐052‐MY3, 112‐2622‐E‐A49‐011, 112‐2221‐E‐A49‐069‐MY3, 113‐ 2622‐8‐A49‐012‐SB, 110‐2222‐E‐009‐006‐MY3, 111‐2923‐E‐A49‐003‐MY3, and 112‐2622‐8‐A49‐013‐SB and the Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Link{\"o}ping University (Faculty Grant SFO‐Mat‐LiU No. 2009‐00971) for financial support. This work was also supported by the Ministry of Education (Taiwan) under 2024 MOE UI‐UAAT. Cooperation Project. F.G. and M.{\v T}. acknowledge funding from the Slovak Research and Development Agency (APVV‐20‐0220), and the Slovak grant agency VEGA (2/0156/25).",
year = "2025",
month = sep,
day = "18",
doi = "10.1002/aelm.202500291",
language = "English (US)",
volume = "11",
journal = "Advanced Electronic Materials",
issn = "2199-160X",
publisher = "John Wiley \& Sons, Ltd.",
number = "15",
}