摘要
We have investigated the electrical properties of GaN-based high electron mobility transistors (HEMT) on N+-type 4H SiC substrates and on sapphire substrate as a reference. The three-terminal off-state breakdown voltage (BV) as a function of gate-drain spacing (LGD) was measured. Both devices possess superior Baliga figure of merit parameters (BFOM= BV3/Ron). For GaN/Sapphire with LGD of 10 μm, Ron is 14.65 mΩ·cm2 and the corresponding BFOM yields a remarkably high value of 9.88 × 108 V2·Ω−1·cm−2. Conversely, GaN/N+ SiC with 20 μm LGD exhibited an Ron of 43.23 mΩ·cm2 and a BFOM value of 1.55 × 107 V2·Ω−1·cm−2. In addition, we perform AFM, XRD, SEM and TEM analysis to further explore the differences in the DC-current properties for these two distinct substrates. The XRD FWHM scales with surface roughness, moreover grain boundaries for GaN-based HEMTs grown on SiC are more distinct compared to Sapphire substrate. This study provide valuable insight into the structural and morphological disparities that may contribute to the observed variations in device performance.
原文 | English |
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頁(從 - 到) | 1117-1124 |
頁數 | 8 |
期刊 | Chinese Journal of Physics |
卷 | 90 |
DOIs | |
出版狀態 | Published - 8月 2024 |